TW200825468A

TW200825468A - Surface light source device and liquid crystal display apparatus having the same

Info

Publication number: TW200825468A
Application number: TW096136509A
Authority: TW
Inventors: Shigeru Aoyama; Kozo Takahashi; Hiroshi Murai
Original assignee: Toray Industries; Toray International Inc
Priority date: 2006-09-29
Filing date: 2007-09-29
Publication date: 2008-06-16
Also published as: WO2008038754A1; CN101606020A; CN101606020B; KR20090101156A; JPWO2008038754A1

Abstract

The present invention is to provide a side-type surface light source having superior light utilization efficiency, high luminance and wide view angle, and a liquid crystal display device using the same. The surface light source of the present invention includes a light source, an light-guide plate having a light-entrance surface that is opposite to the light source and a light-exit surface that is roughly perpendicular to the light-entrance surface, and a first optical film disposed in a direction opposing to the light-exit surface; in the light-guide plate of the surface light source, a plurality of linear trenches or linear protrusions disposed in an approximately parallel manner on the light-exit surface or the surface other than the light-exit surface where is located on the back of the light-exit surface; the first optical film possesses anisotropic diffusivity and is disposed in a manner that the anisotropic diffusivity is characterized by the largest angle of light is roughly parallel to a longitudinal direction of the linear trench or the linear protrusion.

Description

200825468 ，九、發明說明： 4 【發明所屬之技術領域】本發明係關於從背面照射液晶顯示元件等之面光源及裝載此面光源之液晶顯示裝置。【先前技術】電腦、電視或行動電話等之顯示裝置多數採行利用液晶之顯示器。此等液晶顯示元件之本身並非發光體。因此，從背面側使用面光源以將光照射於液晶顯示元件而後進行顯币。此面光源可列舉：於液晶顯示元件之正下方配置複數個光源的正下方型、相對於導光體側端面之方式來配置光源的側邊光源（e d g e 1 i g h t)型。正下方型主要使用於電視用途’側邊光源型除了使用於車導航、監視器、小型電視之外’活用較正下方型爲小型之優點而廣泛使用於行動電話、筆記型電腦、數位相機、數位視訊攝影機等之移動式 ^ 媒體或數位家電的顯示面板等。近年來，由於微細加工技術之進化，像素之微細間距化提昇、更高精細影像顯示成爲可能的。然而，一旦將影像予以微細間距化時，液晶顯示元件之反射率將降低。因此，針對清晰地顯示高精細影像，正尋求更高亮度之面光源。另外’於移動式媒體用途上，在戶外也常被使用。此情形下，利用電池予以驅動後而使用。但是，此時所消耗之電力中，由於面光源之發光而消耗極多的電力。因此， 200825468 . 爲了延長移動式媒體之驅動時間，正尋求面光源之低消耗電力化。然而，並非僅單純地降低電力，面光源之亮度也將降低，在戶外無法得到清晰之影像。因此，正尋求低消耗電力且局売度之面光源。再者，將液晶顯示裝置使用於監視器等之情形下，爲了低成本化、減少薄膜構件數，要求將昂貴之稜鏡片置換成擴散片等。因此，面光源也正尋求高效率化。如此方式，使用側邊光源型面光源之情形下，正積極尋求面光源之高效率化、高亮度化、低成本化。習知面光 . 源之情形，常使用光擴散性墨水之點印刷方式的導光體（例 - 如，參照專利文獻1 )。但是，於如此面光源之情形，無法符合此等之要求。因此，已開發出各種新式之側邊光源 (S1de light)型面光源（例如，參照專利文獻2〜5 )。於專利文獻2中揭示一種面光源，其係在與導光體之光射出面的相反側表面上，使用已形成以光射入面爲中心而配列成約略同心圓形之複數個光擴散圖案的導光體。另外，於專利文獻3中揭示一種面光源，其係在與光射出面相反側之表面上，從光射入面側起，設置間隔而形成圓弧形之溝或突起，並且於射出面側，在形成進行同心圓形異方向性變化之全息照相圖案的導光體上，將稜鏡配列成以光射入面側爲中心之同心圓形的稜鏡片，使稜鏡片朝向導光體之光射入面側後而予以組合。於專利文獻4中揭示一種面光源，其係在導光體之光 200825468 . 射出面，使用組合已使三角形稜鏡垂直配列於光射入面方向的導光體與擴散片。另外，於專利文獻5中揭示一種面光源，其係在與導光體之光射出面的相反側面上，形成垂直於光射入面稜鏡配列的導光體中，將垂直於導光體之稜鏡配列而形成稜鏡之稜鏡片朝向導光體的光射入面側而與側邊面相組合。專利文獻1 :日本專利特開平1 - 1 07406號公報（全頁） r 專利文獻2 :日本專利第3 1 3 5 1 8 3 0號公報（全頁） [" 專利文獻3 :日本專利特開2004- 1 1 1 3 8 3號公報（全頁）專利文獻4 :日本專利特開平8 - 1 79 3 22號公報（全頁）專利文獻5:日本專利特開平1 1 -2245 1 6號公報（全頁）【發明內容】發明所欲解決之技術問穎但是，於專利文獻2、3中揭示的面光源之情形，擴散圖案元件或偏向圖案元件係利用約略同心圓形或同心圓形 ^ 之圖案予以配列。因此，將有面光源大面積化爲困難的問題。另外，從圖案構造上之特徵而言，控制畫面之視野角爲困難的。另外，於專利文獻4中揭示的面光源之情形，將三角形稜鏡配列在其橫剖面平行於燈之方向。因此，將有無法得到充分亮度特性的問題。另外，於專利文獻5中揭示的面光源之情形，藉由組合導光體之光射出面或是其背面之棱鏡配列與垂直於此稜 200825468 . 鏡配列之稜鏡所形成的稜鏡片，可以得到亮度特性優異的备 , 面光源。但是，視野角約爲土 1 0。左右，視野角特性極差。另外，亮度之均勻度也低。本發明之目的係有鑑於相關的習用技術之背景，其係在於提供一種具優越之光利用效率、高亮度且廣視野角之側邊光源型面光源，及使用其之液晶顯示裝置。解決問題之枝術丰跺 ^ 本發明人等鑽硏探討該課題之結果，發現能夠提供一 Γ 種面光源，其係在面光源中，嚐試利用特定構造之導光體與具有異方向擴散性之薄膜而予以構成後，一舉解決該課 - 題，具優越之光利用效率、視野角特性與亮度均勻度，於是完成了本發明。亦即，本發明係如下所示： (1 )本發明之面光源，其係具備：光源、具有相對該光源之至少一光射入面與約略與其垂直之光射出面的導光體、與相對於該光射出面所配置之第丨光學薄膜；於該導光體 Ο 中’在該光射出面或是該光射出面之背面的光非射出面上，約略平行地設置複數個線狀溝或線狀突起；該第1光學薄fl吴係具有異方向擴散性，以使此異方向擴散性成爲最大之方向約略平行於該線狀溝或線狀突起的長邊方向之方式來予以配置。另外，本發明之面光源較宜係由以下之（2 )〜（】5 ) 之任一構造所構成： (2 )記載於該（1 )之面光源，其中該線狀溝或線狀突起 200825468 v 係垂直於其長邊方向之剖面形狀爲從約略圓弧狀、約略吊鐘狀、約略三角形與約略梯形所構成族群中所選出之至少 —*手审° (3 )記載於該（1 )或（2 )之面光源，其中該線狀溝或線狀突起係其長邊方向約略平行於該導光體之光射入面。 (4 )記載於該（1 )〜（3 )中任一項之面光源，其中該線狀溝或線狀突起係設置在該導光體之光非射出面上。 (5 )記載於該（1 )〜（4 )中任一項之面光源，其中在該 r % 第1光學薄膜上設置第2光學薄膜。 . (6 )記載於該（1 )〜（5 )中任一項之面光源，其中該第， 1光學薄膜係於使光從法線方向射入此第1光學薄膜時之擴散性成爲最大之方向上的透過光半値幅D 1 max，與擴散性成爲最小之方向上的透過光半値幅 Dlmin 之比 Dlmax/Dlmin 爲 3 以上。 (7 )記載於該（1 )〜（6 )中任一項之面光源，其中該第 1光學薄膜之反射率爲45%以上，霧度爲70%以上。 (8 )記載於該（6 )或（7 )之面光源，其中該第1光學薄膜之該半値幅Dlmin爲10。以下。 (9 )記載於該（5 )〜（8 )中任一項之面光源，其中該第 2光學薄膜之頂角爲80。〜100。的稜鏡片。 (1 〇 )記載於該（9 )之面光源，其中該稜鏡片係使其長度 (導光）方向，與使光從法線方向射入該第1光學薄膜上時之擴散性成爲最大之方向形成約略平行之方式來予以配 200825468 . 置。 (1 1 )記載於該（9 )或（1 0 )之面光源，其中位於該導光體所設置之線狀溝的光源側之斜面與垂直於該光源1之直線的夾角’或是位於導光體所設置之線狀突起的光源相反側之斜面與垂直於該光源1之直線的夾角爲4 2.5。〜5 0。。 (1 2 )記載於該（5 )〜（8 )中任一項之面光源，其中該第2光學薄膜係於使光從法線方向射入此第2光學薄膜時之擴散性成爲最大之方向上的透過光半値幅D2max，與擴 I. 散性成爲最小之方向上的透過光半値幅 D2min之比 D2max/D2min 爲 5 以上。 (1 3 )記載於該（1 2 )之面光源，其中該第2光學薄膜之反射率爲50%以上，霧度爲70%以上。 (14)記載於該（12)或（13)之面光源，其中該第2光學薄膜之該半値幅D2min爲2°〜50°以下。 (1 5 )記載於該（1 2 )〜（1 4 )中任一項之面光源，其中 C；位於該導光體所設置之線狀溝的光源側之斜面與垂直於該光源1之直線的夾角，或是位於導光體所設置之線狀突起的光源相反側之斜面與垂直於該光源1之直線的夾角爲 20。〜42.5。。另外，本發明之液晶顯示裝置係裝載本發明之面光源。 [發明之效果] 於本發明中，使用複數個線狀溝或線狀突起約略平行所設置之導光體。藉此，能夠控制複數個線狀溝或線狀突 -10- 200825468 S. 起之構造而控制射出特性。其結果，能夠得到高亮度且亮度均勻度高的面光源。另外’於本發明中’以使該線狀溝或線狀突起之長邊方向與具有異方向擴散性之第1光學薄膜的異方向性成爲約略平行之方式來配置。藉此，能夠有效利用光。其結果，能夠得到高亮度之面光源。【實施方式】以下’將參照圖式以說明本發明。第1圖係顯示構成[Technical Field] The present invention relates to a surface light source that illuminates a liquid crystal display element or the like from the back surface and a liquid crystal display device that mounts the surface light source. [Prior Art] Most display devices such as computers, televisions, and mobile phones use liquid crystal displays. These liquid crystal display elements are not themselves illuminants. Therefore, a surface light source is used from the back side to irradiate light to the liquid crystal display element, and then the coin is displayed. The surface light source is a side light source (e d g e 1 i g h t) type in which a light source is disposed directly under the liquid crystal display element and a light source side end surface is disposed opposite to the light guide side end surface. The direct type is mainly used for TV purposes. The side light source type is widely used in mobile phones, notebook computers, digital cameras, digital devices, in addition to car navigation, monitors, and small TVs. Mobile video devices such as video cameras, display panels for digital home appliances, etc. In recent years, due to the evolution of microfabrication technology, fine pitch of pixels has been improved, and higher-definition image display has become possible. However, once the image is finely pitched, the reflectance of the liquid crystal display element is lowered. Therefore, in order to clearly display high-definition images, a higher-luminance surface light source is being sought. In addition, it is often used outdoors in mobile media applications. In this case, use the battery and drive it. However, in the power consumed at this time, a large amount of electric power is consumed due to the light emission of the surface light source. Therefore, 200825468. In order to extend the driving time of mobile media, we are seeking low power consumption of surface light sources. However, instead of simply reducing the power, the brightness of the surface light source will also be lowered, and a clear image cannot be obtained outdoors. Therefore, a surface light source with low power consumption and a low degree of power consumption is being sought. Further, when the liquid crystal display device is used for a monitor or the like, in order to reduce the cost and reduce the number of film members, it is required to replace an expensive sheet with a diffusion sheet or the like. Therefore, the surface light source is also seeking high efficiency. In this way, in the case of using a side light source type surface light source, it is actively seeking to increase the efficiency of the surface light source, increase the brightness, and reduce the cost. Conventional surface light. In the case of a source, a light guide body of a dot printing method using a light diffusing ink is often used (for example, see Patent Document 1). However, in the case of such a surface light source, it is not possible to meet these requirements. Therefore, various new types of side light source (S1de light) surface light sources have been developed (for example, refer to Patent Documents 2 to 5). Patent Document 2 discloses a surface light source which is formed on a surface opposite to the light exit surface of the light guide body, and a plurality of light diffusion patterns which have been formed to be approximately concentric circles centered on the light incident surface. Light guide. Further, Patent Document 3 discloses a surface light source which is formed on a surface on the opposite side to the light exit surface from the light incident surface side to form a circular arc groove or protrusion, and on the exit surface side. On the light guide body forming a hologram pattern for concentric circular directional change, the ruthenium is arranged as a concentric circular ridge piece centered on the light incident surface side, and the ruthenium sheet is directed toward the light guide body. Light is incident on the side of the face and combined. Patent Document 4 discloses a surface light source which is used for light of a light guide body. The exit surface uses a light guide body and a diffusion sheet which are arranged such that a triangular ridge is vertically arranged in the light incident surface direction. Further, Patent Document 5 discloses a surface light source which is formed on a side opposite to a light exit surface of a light guide body and which is formed in a light guide body perpendicular to a light incident surface area, and is perpendicular to the light guide body. Then, the ridges which are arranged to form the ridges are combined with the side faces on the light incident surface side of the light guide. Patent Document 1: Japanese Laid-Open Patent Publication No. Hei No. Hei. No. Hei. No. Hei. No. 1 - 1 07 406 (full page) r Patent Document 2: Japanese Patent No. 3 1 3 5 1 8 3 0 (full page) [" Patent Document 3: Japanese Patent Publication No. 2004-1 1 1 3 3 3 (Full page) Patent Document 4: Japanese Patent Laid-Open No. Hei 8 - 1 79 3 22 (full page) Patent Document 5: Japanese Patent Laid-Open No. 1 1 - 2245 No. 1 SUMMARY OF THE INVENTION PROBLEMS TO BE SOLVED BY THE INVENTION However, in the case of the surface light source disclosed in Patent Documents 2 and 3, the diffusion pattern element or the deflection pattern element utilizes approximately concentric circles or concentric circles. ^ The pattern is assigned. Therefore, it is difficult to increase the area of the surface light source. Further, it is difficult to control the viewing angle of the screen from the characteristics of the pattern structure. Further, in the case of the surface light source disclosed in Patent Document 4, the triangular ridges are arranged in a direction in which the cross section is parallel to the lamp. Therefore, there will be a problem that sufficient brightness characteristics cannot be obtained. In addition, in the case of the surface light source disclosed in Patent Document 5, by combining the light exit surface of the light guide body or the prism arrangement on the back side thereof and the ridge piece formed perpendicular to the edge of the ridge 200825468. A surface light source having excellent brightness characteristics is obtained. However, the viewing angle is approximately 1 0. Left and right, the viewing angle characteristics are extremely poor. In addition, the uniformity of brightness is also low. SUMMARY OF THE INVENTION The object of the present invention is to provide a side light source type surface light source having superior light use efficiency, high brightness and wide viewing angle, and a liquid crystal display device using the same, in view of the related art. The inventors of the present invention have explored the results of this subject and found that it is possible to provide a kind of surface light source, which is used in a surface light source, and attempts to utilize a specific structure of light guide body and has a different direction of diffusivity. After the film was constructed, the subject matter was solved in one fell swoop, and the light utilization efficiency, the viewing angle characteristics, and the brightness uniformity were excellent, and the present invention was completed. That is, the present invention is as follows: (1) The surface light source of the present invention comprises: a light source; a light guide having at least one light incident surface opposite to the light source and a light exit surface perpendicular thereto; a second optical film disposed on the light exit surface; in the light guide body ' a plurality of linear lines are disposed approximately parallel to the light exit surface or the light non-ejecting surface of the back surface of the light exit surface a groove or a linear protrusion; the first optical thin flü system has a diffusivity in an opposite direction, and the direction in which the diffusivity in the different direction is maximized is approximately parallel to a longitudinal direction of the linear groove or the linear protrusion. Configuration. Further, the surface light source of the present invention is preferably constituted by any one of the following (2) to (5): (2) the surface light source described in (1), wherein the linear groove or the linear protrusion 200825468 v The cross-sectional shape perpendicular to the long-side direction is at least selected from the group consisting of approximately arc-shaped, approximately bell-shaped, approximately triangular, and approximately trapezoidal—(*) is described in (1) Or (2) a surface light source, wherein the linear groove or the linear protrusion has a longitudinal direction that is approximately parallel to a light incident surface of the light guide. (4) The surface light source according to any one of (1) to (3) wherein the linear groove or the linear protrusion is provided on a light non-ejecting surface of the light guiding body. (5) The surface light source according to any one of (1) to (4) wherein the second optical film is provided on the r% first optical film. (6) The surface light source according to any one of (1) to (5), wherein the first optical film is formed to maximize diffusivity when light is incident on the first optical film from a normal direction. The ratio Dlmax/Dlmin of the transmitted light half-web D1max in the direction of the transmitted light and the half-width Dlmin of the transmitted light in the direction in which the diffusibility is the smallest is 3 or more. (7) The surface light source according to any one of (1) to (6) wherein the first optical film has a reflectance of 45% or more and a haze of 70% or more. (8) The surface light source according to (6) or (7), wherein the half-web Dlmin of the first optical film is 10. the following. (9) The surface light source according to any one of (5) to (8) wherein the apex angle of the second optical film is 80. ~100. The picture. (1) The surface light source according to (9), wherein the ruthenium has a length (light guiding) direction and a diffusing property when light is incident on the first optical film from a normal direction. The directions are formed in approximately parallel ways to match the 200825468. (1 1 ) The surface light source described in (9) or (10), wherein an angle between a slope of a light source side of a linear groove provided in the light guide body and a line perpendicular to the light source 1 is located or The angle between the slope of the opposite side of the light source of the linear protrusion provided by the light guide body and the line perpendicular to the light source 1 is 42.5. ~5 0. . (1) The surface light source according to any one of (5) to (8) wherein the second optical film is configured to maximize the diffusibility when the light is incident on the second optical film from the normal direction. The ratio D2max/D2min of the transmitted light half-web D2max in the direction and the transmitted light half-web D2min in the direction in which the dispersion is minimized is 5 or more. (1) The surface light source according to (1), wherein the second optical film has a reflectance of 50% or more and a haze of 70% or more. (14) The surface light source according to (12) or (13), wherein the half-web D2min of the second optical film is 2° to 50° or less. (1) The surface light source according to any one of (1 2) to (14), wherein C; a slope on a light source side of the linear groove provided in the light guide body and perpendicular to the light source 1 The angle between the straight line, or the inclined surface on the opposite side of the light source of the linear protrusion provided by the light guide body, is 20 from the line perpendicular to the light source 1. ~42.5. . Further, the liquid crystal display device of the present invention is loaded with the surface light source of the present invention. [Effects of the Invention] In the present invention, a plurality of linear grooves or linear protrusions are used in a substantially parallel arrangement of the light guide members. Thereby, it is possible to control a plurality of linear grooves or linear protrusions to control the injection characteristics. As a result, a surface light source having high luminance and high brightness uniformity can be obtained. Further, in the present invention, the longitudinal direction of the linear groove or the linear protrusion is arranged to be approximately parallel to the anisotropy of the first optical film having the diffusivity in the different direction. Thereby, light can be utilized effectively. As a result, a high-luminance surface light source can be obtained. [Embodiment] Hereinafter, the present invention will be described with reference to the drawings. Figure 1 shows the composition

C 本發明面光源之各構件相對位置關係的分解斜視圖之一例。，如第1圖所示，本發明之面光源具有：光源1、反射板2、導光體3、反射片4、第1光學薄膜5及第2光學薄膜6。於第1圖的例子中，第2光學薄膜6也爲面光源之構 ia兀件。但是’弟2光學薄膜6也可以不存在。〔光源〕 ( 於本發明之面光源中，光源1係向第1圖之y方向延伸的線狀光源。例如，能夠將螢光管或冷陰極管等作爲光源1使用。另外，光源1也可以係使一個或複數個發光二極體（LED )平行配列於第1圖之y方向，使用疑似線狀光源者等。於第1圖的例子中，顯示光源1係配置於導光體3之一側端面的例子，亦即光源1爲一個的例子。第2圖係顯示將光源配置於導光體3之二個以上側端面的例子之圖。 -11- 200825468 、如第2圖（a )所示，二個光源1及反射板2設置在相對導光體3之側端面（光射入面3 1爲二個）的形態；如第2圖 (b ) 、（ c )所示，將光源1及反射板2設置在鄰接導光體 3之側端面的形態（光射入面3 1爲二個（第2圖（c ))及三個（第2圖（b ))，也可以適用於作爲本發明之面光源。〔反射板〕反射板2係配置於光源1之周圍，以使來自光源1之 ^ 光有效射入導光體。反射板2所要求之特性，係較宜反射率爲高的，具體而言，全部光線反射率適宜爲8 5 %以上。更佳爲87%以上，尤以90%以上特別理想。若反射板2之全部光線反射率未滿8 5 %時，無法充分反射從光源1所射出的光，畫面亮度顯著變差。於本發明之面光源中，藉由使反射板2之全部光線反射率成爲8 5 %以上，能夠作成高亮度之面光源。反射板2之材料可列舉：）將樹脂使用於主要之構造 … 成分’將有機、無機之染料及微粒等添加於此中之材料；2 ) 於樹脂中’混合與該樹脂成分爲非相溶性之樹脂、或是由有機、無機粒子所選出之一種以上的材料而熔融擠出後，至少於單向進行拉伸，以使微細氣泡形成於內部之材料；3 ) 將二氧化碳氣體等之氣體注入熔融樹脂後而進行擠壓成形’於內部具有氣泡之材料；4 )將折射率不同的樹脂層予以複數積層之材料；5 )使金屬蒸鍍於1 )〜4 )之反射片的至少單側之材料；及組合此等之材料等，能夠適當採用任 -12- 200825468 一種。此等材料之中，於本發明之面光源中，較宜.使用外觀上具有白色性之材料，尤以使用2 )特別理想。再者，尤以使用下列之薄膜特別理想：於內部形成微細氣泡之薄膜的至少單面上’利用共擠出等方法而積層已添加有機或無機微粒之熱可塑性樹脂，進一步拉伸，而在表層部形成較內層部更微細氣泡之複合膜。反射板2係爲了經歷長期而發揮穩定之反射特性，適 r 宜爲賦與耐光性之材料，亦即含有光安定劑。較宜爲於最外表面層中含有光安定劑。於此，反射板2爲積層構造之情形下，所謂的最外表面層係表示位於最外表面側之層，另外，單層構造之情形係指該層。還有，積層構造之情形，雖然最外表面層存在二層，較宜至少於導光體3側之最外表面層中含有光安定劑。構成反射板2之材料能夠配合用途予以複合後而使用。例如，舉例有爲了防止向反射板2背面之漏光而將金 ^ 屬蒸鍍於背面，或是與黑色等之著色膜或金屬箔相貼合等。另外，於本發明之面光源中，較佳形態之一亦有藉由印刷或蒸鍍而在構成反射板2之材料背面側形成遮光層或傳熱層、導電層。〔導光體〕導光體3係具有4側端面。至少一側端面爲光射入面 3 1。光源1係相對於光射入面3 1，約略平行於光射入面3 1 而予以設置。亦即，導光體3係具有與X z平面約略平行之 -13- 200825468 、二個相對的側端面，及與光射入面3 1相對的側面。導光體3係具有二個主面。二個主面彼此垂直於光射入面31。二個主面之一爲光射出面面3 2之相對面爲光非射出面3 5。於第1圖之伊出面32係約略平行於xy面所配置，朝向xy面約略矩形。另外，除了朝向xz平面之投影圖係外，導光體3也可隨著與光源1分開距離之增薄之約略楔形等。從光源1所照射的光係從導光體3之光射. 導光體3，傳播於導光體3內，再從光射出面於本發明之面光源中，導光體3係由甲基樹脂（PMMA )等之丙烯酸系樹脂、聚碳酸酯系烯、聚異丁烯、聚丁烯、聚甲基戊烯等之聚烯環烯烴系樹脂等之具有一定折射率的透明樹脂的。本發明之面光源係將複數個線狀溝或線狀行地設置在該光射出面3 2或是該光射出面3 2 非射出面3 5上。於第1圖之例子中，約略平行個線狀溝3 3。也可以設置線狀突起以取代線狀線狀溝與線狀突起也可以混合存在。線狀溝與以設置在光射出面32或光非射出面35中任一設置在二者之面。針對複數個線狀溝或線狀突起之配列圖案端面之終端相對，約略 3 2。光射出 U子中，光射之投影圖係約略矩形之加，膜厚變入面3 1射入 3 2射出。丙烯酸甲酯 :樹脂、聚丙烴系樹脂、材料所構成突起約略平之背面的光 ‘地設置複數溝3 3。另外，線狀突起可面，也可以，係並無特 -14- 200825468 別之限制。第3圖係顯示從光射出面3 2側，從其 (第1圖之z方向）觀察本發明面光源之導光體狀溝3 3或線狀突起3 4之配列的示意圖。如第3 導光體3之線狀溝3 3或線狀突起3 4的配列方向線狀溝3 3或線狀突起3 4的配列方向約略垂直於 3 1之情形（第3圖（a ))、約略平行之情形（第3 其中間之情形（第3圖（c ))及組合此等之情形第3圖（d )〜（i ))等。尤其基於能夠得到高效率之觀點，適宜形成與光射入面3 1成爲約略平溝33或線狀突起34爲佳。相較於其他方向之線線狀突起3 4，較宜形成更密之與光射入面3 1約田的線狀溝3 3或線狀突起3 4。另外，此配列並無ί 光體3之整個面內的必要，也可以部分形成。另以爲不同的配列混合存在於同一平面內，或是非的配列混合存在。另外，於第3圖中，顯示線狀溝3 3或線狀\ 從導光體3之一側面起直到另一側面止連續所子，惟並無連續直線之必要，只要於不失去本發範圍內’亦可如第4圖所示，彎曲、或成爲曲線部分斷裂（未圖示）、相鄰的線狀溝3 3或線狀分脫離平行關係（未圖示）。於本發明中’至少複數個線狀溝或線狀突起約略平行予以設置。於此，所謂約略平行係指第法線方向 3時的線圖所示’ ，可列舉：光射入面圖（b ))、 (例如，的光利用行之線狀丨犬溝3 3或平行方向勻形成導外，也可平行關係妄起3 4係形成的例明效果之狀、或是宴起34部之一部分 5圖所示 -15- 200825468 ；般相鄰的線狀溝33或線狀突起34之長邊方向延長角04卜Θ42(以下，將此等夾角稱爲θ4)爲〇±15 還有，所謂0°係意指相鄰的線狀溝33或線狀突起邊方向的延長線係不相交，亦即爲平行。θ 4較宜怎以內，0 4更佳爲0±5。以內。還有，如第4圖所示的線狀溝3 3或線狀突起3 4係如後述之方式來彎曲爲曲線狀之情形，其長邊方向上之主要方向具有的爲Θ 4。另外，複數個線狀溝33或線狀突起34之所或突起並無平行予以形成之必要，也可以包含無平的溝或突起。射入導光體3內之光係以臨界角以上射入光 3 2、光非射出面3 5之期間，於導光體3與空氣之界進行全反射，傳播於導光體3內，並不射向導光體於此，傳播於導光體3內的光之中，衝撞導光體3 成的線狀溝3 3或線狀突起3 4之光係藉由在線狀溝狀突起34之導光體3/空氣界面進行反射而改變其向。其結果，以臨界角以下射入光射出面32，再體3外。亦即，於本發明之面光源中，藉由適當於導光體3之線狀溝33或線狀突起34的形狀、配夠控制面內之射出特性。其結果，能夠作成高亮度亮度均勻度高的面光源。如上所述，於本發明中，線狀溝或線狀突起可在光射出面32或光非射出面35中任一面，也可以線的夾。以內。 34之長 i 〇±1〇。，相鄰，或成夾角設有的溝行關係射出面面重複 3外。中所形 3 3或線行進方向導光制形成列而能且面內以設置設置在 -16- 200825468 二者之面。若線狀溝或線狀突起設置在光非射出面3 5上的話’尤其因爲可以得到高的光利用效率，並且射出角分布之控制爲容易的而較佳。此情形下，導光體3之光射出面 3 2可以爲平滑的，也可以形成各種圖案。若於光射出面3 2 上形成必要以上之圖案時，從光源1起直到與分離的光射入面3 1相對的終端面爲止（於兩側設置光源1之情形則直到中央部爲止），於光進行傳播之前，多數光將從光射出面3 2射出。因此，將有亮度之面內均勻性降低、或中心亮度降低之情形。另外，將有導光體3的大面積化變得困難之情形。因而，將線狀溝或線狀突起設置在光非射出面3 5 之情形下，導光體3之光射出面3 2較宜爲平滑的。於此，所謂平滑係指根據Π S - B 0 6 0 1 ( 2 0 0 1年版），表面粗糙度Ra爲50nm以下。表面粗糙度Ra較宜爲3〇nm以下’更佳爲20nm以下，最好爲l〇nm以下。於本發明之面光源中，藉由使導光體3之光射出面32的Ra成爲50nm以下，即使大面積也能夠形成具優越之亮度特性的面光源。第6圖、第7圖係於本發明之面光源中，列舉垂直於形成導光體3的線狀溝3 3或線狀突起3 4長邊方向之剖面圖的圖式（第1圖之X - z平面）。第6圖係顯示線狀溝3 3 之橫剖面圖，第7圖係顯不線狀突起3 4之橫剖面圖。如第6圖所不’導光體3之線狀溝3 3的適宜形狀可列舉：約略三角形（第6圖（a))、約略梯形（第6圖（b))、約略圓弧形（第6圖（c))、約略吊鐘形（第6圖（d))、此 -17- 200825468 v 等形狀變形後之物（第6圖（e))及此等形狀之混雜物。另外，形狀也可以類似此等形狀。如第7圖所示，線狀突起34的適宜形狀可列舉：約略三角形（第7圖（a))、約略梯形（第7圖（b))、約略圓弧形（第7圖（c))、約略吊鐘形（第7圖（e))、此等形狀變形後之物（第7圖（d))及此等形狀之混雜物。另外，形狀也可以類似此等形狀。於第6圖、第7圖中，雖然線狀溝3 3或線狀突起3 4C. An example of an exploded perspective view of the relative positional relationship of the members of the surface light source of the present invention. As shown in Fig. 1, the surface light source of the present invention comprises a light source 1, a reflector 2, a light guide 3, a reflection sheet 4, a first optical film 5, and a second optical film 6. In the example of Fig. 1, the second optical film 6 is also a constitutive element of a surface light source. However, the "2" optical film 6 may not be present. [Light source] (In the surface light source of the present invention, the light source 1 is a linear light source extending in the y direction of Fig. 1. For example, a fluorescent tube, a cold cathode tube, or the like can be used as the light source 1. One or a plurality of light-emitting diodes (LEDs) may be arranged in parallel in the y direction of FIG. 1 and a suspected linear light source may be used. In the example of FIG. 1, the display light source 1 is disposed in the light guide 3 An example of one side end surface is an example in which the light source 1 is one. Fig. 2 is a view showing an example in which light sources are disposed on two or more side end faces of the light guide body 3. -11- 200825468 , as shown in Fig. 2 a), the two light sources 1 and the reflecting plate 2 are disposed on the side end faces of the light guide body 3 (the light incident surface 31 is two); as shown in Fig. 2 (b) and (c) The light source 1 and the reflecting plate 2 are disposed adjacent to the side end surface of the light guide body 3 (the light incident surface 31 is two (Fig. 2(c)) and three (Fig. 2(b)), It can also be applied to the surface light source of the present invention. [Reflecting plate] The reflecting plate 2 is disposed around the light source 1 so that the light from the light source 1 is effectively incident on the light guide 1. The characteristics required for the reflector 2 are preferably higher, and specifically, the total light reflectance is suitably 85 % or more. More preferably 87% or more, particularly preferably 90% or more. When the total light reflectance of the reflecting plate 2 is less than 85%, the light emitted from the light source 1 cannot be sufficiently reflected, and the brightness of the screen is remarkably deteriorated. In the surface light source of the present invention, all the light reflected from the reflecting plate 2 is reflected. The rate is 85% or more, and a high-brightness surface light source can be produced. The material of the reflecting plate 2 is: a resin used for a main structure... a component 'a material in which an organic or inorganic dye, fine particles, or the like is added; 2) After being melt-extruded in a resin by mixing a resin which is incompatible with the resin component or one or more materials selected from organic or inorganic particles, it is stretched at least in one direction to make fine bubbles a material formed inside; 3) a material in which a gas such as carbon dioxide gas is injected into a molten resin and then extruded to form a material having bubbles therein; and 4) a material in which a resin layer having a different refractive index is laminated; 5) A material in which at least one side of the reflection sheet of 1) to 4) is vapor-deposited; and a material such as these is combined, and any one of -12-200825468 can be suitably used. Among these materials, in the surface light source of the present invention, it is preferred to use a material which is white in appearance, and particularly preferably 2). Further, it is particularly preferable to use a film which is formed by laminating at least one surface of a film in which fine bubbles are formed, by a method such as co-extrusion, and further adding a thermoplastic resin to which organic or inorganic fine particles have been added, and further stretching. The surface layer portion forms a composite film having finer bubbles than the inner layer portion. The reflecting plate 2 exhibits stable reflection characteristics for a long period of time, and is preferably a material imparting light resistance, that is, containing a light stabilizer. It is preferred to contain a light stabilizer in the outermost surface layer. Here, in the case where the reflecting plate 2 has a laminated structure, the so-called outermost surface layer indicates the layer on the outermost surface side, and the case of the single layer structure means the layer. Further, in the case of the laminated structure, although the outermost surface layer has two layers, it is preferable to contain the light stabilizer in at least the outermost surface layer on the side of the light guide 3. The material constituting the reflecting plate 2 can be used in combination with the use. For example, in order to prevent light leakage to the back surface of the reflector 2, the metal is vapor-deposited on the back surface, or is bonded to a color film or a metal foil such as black. Further, in the surface light source of the present invention, in one of the preferred embodiments, a light shielding layer, a heat transfer layer, and a conductive layer are formed on the back side of the material constituting the reflector 2 by printing or vapor deposition. [Light Guide] The light guide 3 has four end faces. At least one of the end faces is a light incident surface 31. The light source 1 is disposed approximately parallel to the light incident surface 31 with respect to the light incident surface 31. That is, the light guide 3 has -13 to 200825468 approximately parallel to the X z plane, two opposite side end faces, and a side opposite to the light incident surface 31. The light guide 3 has two main faces. The two main faces are perpendicular to each other to the light incident surface 31. One of the two main faces is the opposite side of the light exit face 3 2 being the light non-ejection face 35. In Fig. 1, the output 32 is arranged approximately parallel to the xy plane, and is approximately rectangular toward the xy plane. Further, in addition to the projection map toward the xz plane, the light guide 3 may be approximately wedge-shaped or the like as the distance from the light source 1 is increased. The light emitted from the light source 1 is emitted from the light of the light guide 3. The light guide 3 is propagated in the light guide 3, and then the light exit surface is in the surface light source of the present invention, and the light guide 3 is made of A. A transparent resin having a constant refractive index such as an acrylic resin such as a base resin (PMMA), a polyalkylene olefin resin such as polycarbonate olefin, polyisobutylene, polybutene or polymethylpentene. In the surface light source of the present invention, a plurality of linear grooves or linear lines are provided on the light exit surface 32 or the light exit surface 3 2 non-emission surface 35. In the example of Fig. 1, approximately linear grooves 3 3 are parallel. It is also possible to provide a linear protrusion instead of a linear line groove and a linear protrusion. The linear grooves are provided on either of the light exit surface 32 or the light non-eject surface 35. The end of the end face of the arrangement pattern of the plurality of linear grooves or linear protrusions is approximately 32. When the light is emitted from the U, the projection of the light is approximately rectangular, and the film thickness is changed into the surface 3 1 and injected into the lens 3 2 . Methyl acrylate: a resin composed of a resin, a polypropylene resin, or a material. The light on the back surface of the protrusion is approximately flat. In addition, the linear protrusions may be surfaced, or may be other than the limit of -14-200825468. Fig. 3 is a view showing the arrangement of the light guiding body grooves 3 3 or the linear protrusions 34 of the surface light source of the present invention as viewed from the side of the light exiting surface 3 2 (in the z direction of Fig. 1). For example, the alignment direction of the linear groove 3 3 of the third light guide 3 or the alignment direction of the linear protrusions 3 4 or the arrangement of the linear protrusions 3 4 is approximately perpendicular to 3 1 (Fig. 3 (a) ), approximately parallel (the third case (Fig. 3 (c)) and the combination of these cases, figure 3 (d) ~ (i)). In particular, it is preferable to form the light incident surface 31 into the approximate flat groove 33 or the linear protrusion 34 from the viewpoint of obtaining high efficiency. The linear grooves 3 3 or the linear protrusions 34 which are denser than the light incident surface 31 are preferably formed in comparison with the linear protrusions 34 in other directions. In addition, this arrangement is not necessary in the entire surface of the light body 3, and may be partially formed. In addition, it is thought that different types of mixed mixtures exist in the same plane, or a mixture of non-columns exists. In addition, in FIG. 3, it is shown that the linear groove 3 3 or the linear shape is continuous from one side of the light guide body 3 to the other side, but there is no need for a continuous straight line, as long as the hair is not lost. In the range ', as shown in Fig. 4, it may be curved, or the curved portion may be broken (not shown), the adjacent linear grooves 3 3 or the linear portions may be separated from the parallel relationship (not shown). In the present invention, at least a plurality of linear grooves or linear protrusions are disposed approximately in parallel. Here, the term "about parallel" refers to the line diagram "in the normal line direction 3", and may be exemplified by the light incident surface pattern (b)). (For example, the light is used in the line of the dog's dog groove 3 or Parallel direction is formed to form an out-of-conductor, or it can be paralleled to pick up the shape effect of the formation of the 34 series, or a part of 34 parts of the banquet 5 shown in Figure -15-200825468; the adjacent linear groove 33 or The longitudinal direction extension angle 04 of the linear protrusions 34 (hereinafter, referred to as θ4) is 〇±15. The so-called 0° means the direction of the adjacent linear grooves 33 or the linear protrusions. The extension lines are not intersecting, that is, parallel. θ 4 is preferably within, and 0 4 is preferably 0±5. Also, the linear groove 3 3 or the linear protrusion 3 as shown in Fig. 4 4 is a curved shape as described later, and the main direction in the longitudinal direction has Θ 4. Further, a plurality of linear grooves 33 or linear protrusions 34 are not formed in parallel. It is also necessary to include a flat groove or a protrusion. The light incident into the light guide 3 is incident on the light 3 at a critical angle or more, and the light is not emitted. During the period of 3 5, the light guide 3 and the air are totally reflected and propagated in the light guide 3, and do not emit the light guide body, but propagate through the light in the light guide 3 to collide with the light guide. The light of the linear groove 3 3 or the linear protrusion 34 formed by the body 3 is reflected by the light guide 3/air interface of the linear groove-like protrusion 34 to change its direction. As a result, it is incident at a critical angle or less. The light exiting surface 32 is external to the body 3. That is, in the surface light source of the present invention, the in-plane emission characteristics are controlled by the shape of the linear groove 33 or the linear protrusion 34 suitable for the light guide body 3. As a result, it is possible to form a surface light source having high brightness uniformity. As described above, in the present invention, the linear groove or the linear protrusion may be on either the light exit surface 32 or the light non-emission surface 35, or The length of the line is 34. The length of the 34 is i 〇±1〇. The adjacent groove or the angle of the groove formed by the angle of the exit is repeated 3 times. The shape of the line 3 3 or the direction of the line guides the light to form a column. It can be set in the surface in the range of -16- 200825468. If the linear groove or the linear protrusion is set in the light non-ejecting On the face 35, 'especially because high light utilization efficiency can be obtained, and control of the emission angle distribution is easy, and in this case, the light exit surface 32 of the light guide 3 can be smooth or Various patterns are formed. When a pattern of more than necessary is formed on the light exit surface 3 2 , from the light source 1 to the end surface opposite to the separated light incident surface 31 (the light source 1 is disposed on both sides until the center) Until the light is transmitted, most of the light is emitted from the light exit surface 32. Therefore, the in-plane uniformity of the luminance is lowered or the center luminance is lowered. Further, there is a case where it is difficult to increase the area of the light guide body 3. Therefore, in the case where the linear groove or the linear protrusion is provided on the light non-emission surface 35, the light exit surface 32 of the light guide 3 is preferably smooth. Here, the smoothing means that the surface roughness Ra is 50 nm or less in accordance with Π S - B 0 6 0 1 (2000 edition). The surface roughness Ra is preferably less than 3 〇 nm and more preferably 20 nm or less, more preferably 10 Å or less. In the surface light source of the present invention, by setting the Ra of the light exit surface 32 of the light guide 3 to 50 nm or less, a surface light source having excellent luminance characteristics can be formed even in a large area. Fig. 6 and Fig. 7 are diagrams showing a cross-sectional view perpendicular to the longitudinal direction of the linear groove 3 3 or the linear protrusion 34 forming the light guide 3 in the surface light source of the present invention (Fig. 1) X-z plane). Fig. 6 is a cross-sectional view showing the linear groove 3 3, and Fig. 7 is a cross-sectional view showing the linear protrusion 34. The suitable shape of the linear groove 3 3 of the light guide body 3 as shown in Fig. 6 can be exemplified by an approximately triangular shape (Fig. 6 (a)), a substantially trapezoidal shape (Fig. 6 (b)), and an approximately circular arc shape ( Figure 6 (c)), approximate bell-shaped (Fig. 6 (d)), this -17-200825468 v and other shapes (Fig. 6 (e)) and hybrids of these shapes. In addition, the shape can be similar to these shapes. As shown in Fig. 7, a suitable shape of the linear protrusions 34 is approximately triangular (Fig. 7(a)), approximately trapezoidal (Fig. 7(b)), and approximately circular arc (Fig. 7(c) ), approximately a bell-shaped shape (Fig. 7(e)), a deformed object (Fig. 7(d)), and a mixture of such shapes. In addition, the shape can be similar to these shapes. In Fig. 6 and Fig. 7, although the linear groove 3 3 or the linear protrusion 3 4

C 之剖面形狀顯示對稱形者，但是並不受此等對稱形所限定，光射入面31側與其相反側也可以爲非對稱之形狀。另外，也可以混合存在線狀溝33與線狀突起34。位於導光體3中所設置之線狀溝3 3上的光源1側之斜面與垂直於該光源1之直線的夾角0 1，或是位於導光體3 所設置之線狀突起34上的光源1相反側之斜面與垂直於該光源1之直線的夾角Θ2適宜爲20〜50。。若01或02爲 i 該範圍的話，能夠得到光利用效率高的面光源。所謂位於導光體3中所設置之線狀溝3 3上的光源1側之斜面與垂直於該光源1之直線的夾角，係如第6圖（a)、第6圖（b )所示，平行於X y面且垂直於光源1之直線L1 與位於線狀溝3 3的光源1側之斜面的夾角θ 1。還有，如第6圖（c)〜（e )所示，於一斜面內，斜面的夾角改變之情形，將其斜面切線之斜率平均値設爲位於導光體3中所設置之線狀溝3 3的光源1側之斜面與垂直於該光源1之直線 -18- 200825468 的夾角0 1。另外，所謂位於導光體3中所設置之線狀突起3 4的光源1相反側之斜面與垂直於該光源1之直線的夾角’係指如第7圖（a)、（ b )所示，平行於xy面且位在垂直於光源 1之直線L 1與線狀突起3 4之光源1相反側之斜面的夾角 0 2。還有，如第7圖（c)〜（e )所示’於一斜面內，斜面的夾角改變之情形，將其斜面切線之斜率平均値設爲位於線狀突起3 4的光源1相反側之斜面與垂直於該光源1之直線的夾角0 2。如此方式，藉由控制位於導光體3中所設置之線狀溝 3 3的光源1側之斜面與垂直於該光源1之直線的夾角0 1，或是控制位於導光體3中所設置之線狀突起34的光源1相反側之斜面與垂直於該光源1之直線的夾角 0 2，便能夠控制來自導光體3之光射出特性。還有，若或02未滿2 0°或超過50°時，將有來自導光體3的光之射出光量減少之情形。另外，使用複數個光源之情形下，只要於至少一光源與線狀溝3 3或線狀突起3 4之間，0 1或0 2爲該値的話即可。位於導光體3中所設置之線狀溝3 3的光源1側之斜面或位於導光體3中所設置之線狀突起3 4的光源1相反側之斜面較宜爲平滑的。此處所謂平滑係指根據Π S _ B 〇 6 〇 i (2 0 0 1年版），於測定該斜面的表面粗糙度r &時，其値爲5 0nm以下。更佳爲20nm以下，最好爲_以下，尤 -19- 200825468 # ：以5nm以下特別理想。若相對於導光體3之線狀溝33或線狀突起34的光源1之斜面的表面粗糙度Ra超過50nm時，於線狀溝33或線狀突起34表面上之光反射效率將降低，其結果，將有導光體3的光利用效率降低之情形。藉由使位於導光體3中所設置之線狀溝3 3的光源1側之斜面或位於導光體3中所設置之線狀突起3 4的光源1相反側之斜面的表面粗糙度Ra成爲50nm以下，能夠提高線狀溝33或線 ^ 狀突起3 4表面上之光反射效率。其結果，能夠作成光利用效率高的面光源。另外，線狀溝3 3或線狀突起3 4之間的平坦面係根據 JIS-B060K 2001年版），表面粗糙度Ra適宜爲50nm以下。較宜爲20nm以下，更佳爲10nm以下，尤以5nm以下特別理想。於本發明中，若線狀溝3 3或線狀突起3 4之間的平坦面R a超過5 0 n m時，從光源1起直到與分離的光射入面 3 1相對的終端面爲止（於兩側設置光源1之情形係直到中 , 央部爲止），於光進行傳播之前，多數光將從光射出面3 2 射出。因此，將有亮度之面內均勻性降低、或中心亮度降低之情形。藉由使線狀溝3 3或線狀突起3 4之間平坦面的 Ra成爲50nm以下，即使大面積也能夠形成具優越之亮度特性的面光源。於本發明之面光源中’導光體3之線狀溝3 3的深度 H1 (第6圖）或線狀突起34的高度H2(第7圖）適宜爲1 〜500//m。較宜爲1〜200//m’更佳爲1〜i〇0//m。若H1、 -20- 200825468 ： Η 2未滿1 // m時，線狀溝3 3或線狀突起3 4之大小將過小而易於變得難以成形，另外，即使能夠成形，也將有使傳播於導光體3內之光方向改變的機能惡化之情形。另外， HI、H2若超過500 // m時，也易於變得難以成形。藉由使導光體3之線狀溝3 3的深度Η1或線狀突起3 4的高度Η 2 成爲1〜5 00 // m之範圍內，能夠兼顧導光體3之成形性與光之利用效率。 r 射入導光體3內而進行傳播的光之中，衝撞線狀溝3 3 或線狀突起3 4之光係使其行進方向改變，以臨界角以下之角度射入光射出面32，再射向導光體3外。因此，隨著與光源1分開距離之增加，傳播於導光體3內之光量將減少。亦即，依位置所造成之光衝撞機率爲相同的。因而，僅形成相同形狀、相同尺寸的線狀溝33或線狀突起34之情形下，與導光體3內之光量成比例，與光源1接近側將成爲高亮度。爲了使與光源1分離側之亮度設爲相等於光源側 1之亮度，隨著與光源1分開距離之增加，可以提高對線狀溝3 3或線狀突起3 4之光衝撞機率。具體而言，隨著與光源1分開距離之增加，可列舉之方法如下：（A )提高顯示於第6圖、第7圖之線狀溝3 3的深度Η1或線狀突起34 的高度Η2 ; ( Β )細化線狀溝33或線狀突起34的間距； (C )提高顯示於第6圖、第7圖之線狀溝3 3的深度η 1 或線狀突起3 4的高度Η2，並且細化線狀溝3 3或線狀突起 3 4的間距等。 -21 - 200825468 還有’於（A )或（C )之方法中，隨著與光源1分開距離之增加，加深線狀溝33的深度H1或加高線狀突起34 的高度H2之情形下，最好使線狀溝3 3的深度η 1或線狀突起34的局度Η2於1〜500// m之範圍內改變。力外’導先體3之各線狀溝3 3的丨朵度η 1或線狀突起 34的高度Η2可以於一條線狀溝或線狀突起之長邊方向爲均勻的深度Η1或高度Η2,也可以深度Η1或高度Η2改變。深度Η 1或高度Η2改變之例子，係於平行於光源1之方向，來自光源1之光將有難以到達的部分之情形下，能夠提高此部分之線狀溝33的深度Η1或線狀突起34的高度Η2 ; 或是將有光過剩傳播的部分之情形下，能夠縮小線狀溝3 3 的深度Η 1或線狀突起34的高度Η2。其結果，因爲能夠調整導光體3之面內的射出光量，而作成所期望之亮度分布。另外，導光體3之線狀溝3 3或線狀突起3 4的重複單位的間距Ρ適宜爲10〜1000//m。較宜爲20〜600//m，更佳爲3 0〜4 0 0 // m。若間距P未滿1 〇 // m時，間距將過小而易於變得難以成形。另外，若間距P超過1 〇〇〇 // m時，將有線狀溝33或線狀突起34所形成之部分與未形成之部分的亮度均勻度降低之情形。本發明面光源之情形，藉由使導光體3之線狀溝3 3或線狀突起3 4的間距P成爲1 〇〜 1 000 // m之範圍內，能夠兼顧導光體3之成形性與光利用效率。還有，利用該（B )或（C )之方法，根據相距光源之距離，以使線狀溝3 3或線狀突起3 4的間距p改變之情 -22- 200825468 9 : 形下，也適宜於10〜1000/zm之範圍內予以改變。只要光源1爲螢光管或冷陰極管之線狀光源的話，導光體3之光射入面3 1的形狀並無特別之限制。另一方面，使一個或複數個發光二極體（LED )平行於y方向而予以配列’作成疑似的線狀光源作爲光源1使用之情形下，將有相當於LED之正面的部分成爲亮線、或相當於LED-LED 間之正面的部分成爲暗線之情形。此情形下，最好將光射 ^ 入面3 1之形狀作成約略圓弧狀、約略稜鏡狀、約略梯形、 \ 約略圓頂形等之凹凸形狀。藉由作成如此之形狀，不僅能夠提高光射入導光體3內之效率，也能夠於光射入時適度使光予以擴散。其結果，即使於導光體3之光射入面3 1附近，也能夠使亮度予以均勻化。於本發明之面光源中，導光體3的厚度係視畫面尺寸而定。通常爲0.1〜20mm，適宜爲0.1〜15mm，更佳爲〇.1 〜10mm。導光體3的厚度並無一定之必要，也可以隨著遠 k，離光射入面31而變薄。另外，導光體3的厚度較光源1的厚度爲薄之情形，爲了光利用效率之提高，也可以增加導光體3之光射入面3 1附近的厚度，並且，形成傾斜部而僅薄化光射出面3 2之部分。用於本發明面光源之導光體3係依如下之方式所製造。本發明之導光體3能夠利用射出成形、印壓法等方法而加以製作。另外，於厚度0.8mm以下之薄型導光體、或是畫面尺寸1 5吋以上的大面積導光體之情形’基於能夠高 -23- 200825468 礞、精密、再現性佳地成形線狀溝33或線狀突起34之觀點， t 適宜利用印壓法進行。還有，導光體3的膜厚爲〇·8 // m以上且畫面尺寸1 5吋以下之情形，能夠適當採用射出成形、印壓法中任一種。印壓法之情形，藉由成形後切成所要求之形狀，硏磨側面部分後，而能夠得到導光體3。構成導光體3之樹脂適宜使用PMMA等之丙烯酸系樹 f 脂；聚碳酸酯系樹脂；聚丙烯、聚異丁烯、聚丁烯、聚甲基戊烯等聚烯烴系樹脂、環烯烴系樹脂等之具有一定折射率的透明樹脂材料。〔反射片〕反射片4係設置在導光體3之光非射出面3 5側。反射片4係將從導光體3之光非射出面3 5所射出的光反射至導光體3 °反射片4之特性、材質、構造等係與該反射板2 相同。 ‘ 〔第1光學薄膜〕本發明之面光源，其特徵係在導光體3之光射入面3 1 上’設置特定之第丨光學薄膜5。於本發明中，第1光學薄膜5係具有異方向擴散性， & ί吏此異方向擴散性爲最大之方向成爲約略平行於該線狀溝33或線狀突起34的長邊方向之方式來予以配置。於本說明書中’所謂「異方向擴散性」係指使用自動變角光度 g十’相對反射率係每隔丨。測定使光束從垂直於薄膜面之方 -24- 200825468 向射入時所透過之光射出角分布，透過光之擴散方式係根據測定方向而有所不同。自動變角光度計最好使用習知裝置。例如，最好爲自動變角光度計GP200 (日本村上色彩技術硏究所製）或具有與此同等以上機能之自動變角光度計。具體而言，如第8圖所示，係指於橫軸設爲射出角、縱軸設爲光量而加以作圖時，相對於朝法線方向之射出量 T〇’將一半光量（T。/ 2)時之角度寬設爲半値幅d，此半値幅D係根據測定方向而有所不同。於此，異方向擴散性係從更平滑面射入所測定之値。另外’所謂「異方向擴散性成爲最大之方向」係指該透過光之半値幅D成爲最大之測定方向。另一方面，所謂「異方向擴散性成爲最小之方向」係指該透過光之半値幅 D成爲最小之測定方向。本發明面光源之情形，係使第1 光學薄膜5之異方向擴散性成爲最大之方向與導光體3之線狀溝3 3或線狀突起34之長邊方向予以約略平行配置。藉此’能夠有效利用從導光體3射出的光。其結果，能夠作成高亮度之面光源。於此，所謂約略平行係指如第9圖所示’線狀溝3 3或線狀突起34之長邊方向（d 1 )，與第1 光學薄膜5之異方向擴散性成爲最大之方向（d2 )的夾角 05爲〇±15。以內。較宜爲0±10。以內，更佳爲0±5。以內。還有’如上所述，相鄰的線狀溝3 3或線狀突起3 4成爲彎曲、或成爲曲線狀之情形，將其主要方向與第丨光學薄膜5之異方向擴散性成爲最大之方向的夾角設爲θ 5。 -25- 200825468 該第1光學薄膜5係於使光從法線方向射入時之異方向擴散性成爲最大之方向上的透過光半値幅Dlmax，與使光從法線方向射入時之異方向擴散性成爲最小之方向上的透過光半値幅Dlmin之比Dlmax/Dlmin適宜爲3以上。 Dlmax/Dlmin$父且爲5以上、Dlmax/Dlmin更佳爲7以上。若Dlmax/Dlmin未滿3時’將有從導光體3之光射出面32 所射出的光超過必要之散亂、亮度降低之情形。藉由使第 1先學薄吴5之Dlmax/Dlmin成爲3以上，能夠使從導光體3之光射出面3 2所射出的光予以高效率透過。其結果，夠得到局売度之面光源。另外，使用後述之第2光學薄膜6之情形下，也能夠得到高亮度提高之效果。另外，第1光學薄膜5係使光從法線方向射入時之異. 方向擴散性成爲最小之方向上的透過光半値幅D 1 min適宜爲10°以下。較宜爲7。以下，更佳爲5。以下。若Dlmin超過10°時’將有從導光體3之光射出面32所射出的光超過必要之散亂、亮度降低之情形。於本發明之面光源中，藉由使弟1先學薄膜5之Dlmin成爲10。以下，能夠使從導光體3之光射出面32所射出的光予以高效率透過。其結果，目匕夠得到局売度之面光源。另外，使用後述之第2光學薄膜6之情形下，也能夠得到高亮度提高之效果。另外’第1光學薄膜5之全部光線反射率適宜爲45% 以上。全部光線反射率較宜爲5 0 %以上。此處所謂全部光線反射率係指於使用光源（適宜爲標準光源、參照ns -26- 200825468 . Z-8 720 ( 2000年版））而使光射入薄膜時，透過薄膜之光量相對於射入光量的比例。還有，如凹凸形狀形成於光學薄膜5的單側表面之情形下，將從更平滑表面射入後而測出之値設爲全部光線反射率。如凹凸形狀形成於光學薄膜 5的兩側面之情形下或兩側面爲平滑之情形下，將從兩側面射入後而測出値之中的較大値設爲全部光線反射率。若第1光學薄膜5之全部光線反射率未滿45 %時，將有無法有效利用從導光體3射出的光之情形。如此方式，藉由使The cross-sectional shape of C shows a symmetrical shape, but is not limited by such a symmetrical shape, and the side of the light incident surface 31 and the opposite side thereof may have an asymmetrical shape. Further, the linear grooves 33 and the linear protrusions 34 may be mixed. The angle between the slope of the light source 1 on the linear groove 3 provided in the light guide 3 and the line perpendicular to the light source 1 is 1 or on the linear protrusion 34 provided by the light guide 3. The angle Θ2 between the slope of the opposite side of the light source 1 and the line perpendicular to the light source 1 is suitably 20 to 50. . When 01 or 02 is i in this range, a surface light source having high light use efficiency can be obtained. The angle between the slope of the light source 1 side on the linear groove 3 provided in the light guide 3 and the line perpendicular to the light source 1 is as shown in Fig. 6(a) and Fig. 6(b). An angle θ 1 between the straight line L1 parallel to the X y plane and perpendicular to the light source 1 and the inclined surface on the light source 1 side of the linear groove 3 3 . Further, as shown in Fig. 6 (c) to (e), in the case where the angle of the inclined surface is changed in a slope, the slope of the oblique line tangent is set to be linearly located in the light guide body 3. The slope of the light source 1 side of the groove 3 3 is at an angle 0 1 to the line -18-200825468 perpendicular to the light source 1. Further, the angle between the slope of the opposite side of the light source 1 of the linear protrusions 34 provided in the light guide 3 and the line perpendicular to the light source 1 is as shown in Figs. 7(a) and (b). An angle θ parallel to the xy plane and located at a slope perpendicular to the line L 1 of the light source 1 and the side opposite to the light source 1 of the linear protrusion 34. Further, as shown in Fig. 7 (c) to (e), in the case where the angle of the inclined surface is changed in a slope, the slope of the oblique line tangent is set to be on the opposite side of the light source 1 of the linear protrusion 34. The angle between the slope and the line perpendicular to the light source 1 is 0 2 . In this manner, by controlling the angle between the slope of the light source 1 side of the linear groove 3 provided in the light guide 3 and the line perpendicular to the light source 1 or controlling the light body 3 to be disposed. The angle between the slope of the opposite side of the light source 1 of the linear protrusion 34 and the line perpendicular to the line of the light source 1 can control the light emission characteristics from the light guide 3. Further, if or 02 is less than 20° or exceeds 50°, the amount of light emitted from the light guide 3 is reduced. Further, in the case of using a plurality of light sources, it is sufficient that 0 1 or 0 2 is between the at least one light source and the linear grooves 3 3 or the linear protrusions 34. The slope of the light source 1 side of the linear groove 3 provided in the light guide 3 or the slope of the opposite side of the light source 1 of the linear protrusion 34 provided in the light guide 3 is preferably smooth. Here, the smoothing means that when 表面 S _ B 〇 6 〇 i (2000 edition), when the surface roughness r & of the slope is measured, the 値 is 50 nm or less. More preferably, it is 20 nm or less, preferably _ or less, especially -19-200825468 # : It is particularly desirable to be 5 nm or less. When the surface roughness Ra of the inclined surface of the light source 1 with respect to the linear groove 33 of the light guide 3 or the linear protrusion 34 exceeds 50 nm, the light reflection efficiency on the surface of the linear groove 33 or the linear protrusion 34 is lowered. As a result, there is a case where the light use efficiency of the light guide 3 is lowered. The surface roughness Ra of the slope on the side opposite to the light source 1 on the side of the light source 1 of the linear groove 3 provided in the light guide 3 or on the opposite side of the light source 1 provided in the light guide 3 When the thickness is 50 nm or less, the light reflection efficiency on the surface of the linear groove 33 or the line-like protrusion 34 can be improved. As a result, a surface light source having high light utilization efficiency can be produced. Further, the flat surface between the linear groove 3 3 or the linear protrusion 34 is in accordance with JIS-B060K 2001 edition, and the surface roughness Ra is preferably 50 nm or less. It is preferably 20 nm or less, more preferably 10 nm or less, and particularly preferably 5 nm or less. In the present invention, when the flat surface R a between the linear groove 33 or the linear protrusion 34 exceeds 50 nm, the light source 1 is up to the end surface opposite to the separated light incident surface 31 ( When the light source 1 is disposed on both sides, until the middle portion and the center portion are irradiated, most of the light is emitted from the light exit surface 3 2 before the light propagates. Therefore, there is a case where the in-plane uniformity of luminance is lowered or the center luminance is lowered. By making the Ra of the flat surface between the linear groove 33 and the linear protrusion 34 450 nm or less, a surface light source having excellent luminance characteristics can be formed even in a large area. In the surface light source of the present invention, the depth H1 (Fig. 6) of the linear groove 3 of the light guide 3 or the height H2 (Fig. 7) of the linear protrusion 34 is preferably 1 to 500 / / m. More preferably, it is 1 to 200 / / m', and more preferably 1 to i 〇 0 / / m. If H1, -20-200825468: Η 2 is less than 1 // m, the size of the linear groove 3 3 or the linear protrusion 34 will be too small to be easily formed, and even if it can be formed, it will be The deterioration of the function of the light direction propagating in the light guide 3 deteriorates. Further, when HI or H2 exceeds 500 // m, it tends to be difficult to form. By making the depth Η1 of the linear groove 3 of the light guide 3 or the height Η 2 of the linear protrusion 34 into the range of 1 to 500 // m, the formability of the light guide 3 and the light can be achieved. usage efficiency. r among the light that is incident into the light guide 3 and propagates, the light that strikes the linear groove 3 3 or the linear protrusion 34 changes its traveling direction, and enters the light exit surface 32 at an angle lower than the critical angle. Re-shooting outside the light guide 3. Therefore, as the distance from the light source 1 increases, the amount of light propagating in the light guide 3 will decrease. That is, the light collision rate caused by the position is the same. Therefore, in the case where only the linear grooves 33 or the linear protrusions 34 having the same shape and the same size are formed, the amount of light in the light guide body 3 is proportional to the light source 1, and the light source 1 is highly bright. In order to make the brightness on the side separated from the light source 1 equal to the brightness on the light source side 1, as the distance from the light source 1 increases, the probability of light collision with the linear groove 3 or the linear protrusion 34 can be increased. Specifically, as the distance from the light source 1 increases, the method is as follows: (A) increasing the depth Η1 of the linear groove 3 3 shown in FIGS. 6 and 7 or the height 线 2 of the linear protrusion 34 ( Β ) refining the pitch of the linear grooves 33 or the linear protrusions 34; (C) increasing the depth η 1 of the linear grooves 3 3 shown in FIGS. 6 and 7 or the height 线 2 of the linear protrusions 34 And the pitch of the linear groove 3 3 or the linear protrusion 34 is refined. -21 - 200825468 In the method of (A) or (C), as the distance from the light source 1 increases, the depth H1 of the linear groove 33 is deepened or the height H2 of the linear protrusion 34 is raised. Preferably, the depth η 1 of the linear groove 3 3 or the locality Η 2 of the linear protrusion 34 is changed in the range of 1 to 500 / / m. The entanglement degree η 1 of each of the linear grooves 3 3 or the height Η 2 of the linear protrusions 34 may be a uniform depth Η1 or height Η2 in the longitudinal direction of a linear groove or a linear protrusion. It can also be changed to depth Η1 or height Η2. An example in which the depth Η 1 or the height Η 2 is changed is in a direction parallel to the light source 1, and in the case where the light from the light source 1 has an hard-to-reach portion, the depth Η1 or the linear protrusion of the linear groove 33 of the portion can be raised. The height 342 of 34; or the portion where the light is excessively propagated, the depth Η 1 of the linear groove 3 3 or the height Η 2 of the linear protrusion 34 can be reduced. As a result, the amount of light emitted in the plane of the light guide 3 can be adjusted to produce a desired luminance distribution. Further, the pitch Ρ of the repeating unit of the linear groove 3 3 or the linear protrusion 34 of the light guide 3 is preferably 10 to 1000 / / m. It is preferably 20 to 600 / / m, more preferably 3 0 to 4 0 0 / m. If the pitch P is less than 1 〇 // m, the pitch will be too small to be easily formed. Further, when the pitch P exceeds 1 〇〇〇 // m, the brightness uniformity of the portion formed by the linear groove 33 or the linear protrusion 34 and the unformed portion is lowered. In the case of the surface light source of the present invention, the formation of the light guide 3 can be achieved by making the pitch P of the linear groove 3 3 or the linear protrusion 34 of the light guide 3 in the range of 1 〇 to 1 000 // m. Sex and light utilization efficiency. Further, by the method of (B) or (C), depending on the distance from the light source, the pitch p of the linear groove 3 or the linear protrusion 34 is changed to be -22-200825468 9 : It is suitable to be changed within the range of 10 to 1000/zm. The shape of the light incident surface 31 of the light guide 3 is not particularly limited as long as the light source 1 is a linear light source of a fluorescent tube or a cold cathode tube. On the other hand, when one or a plurality of light-emitting diodes (LEDs) are arranged in parallel with the y-direction and a suspected linear light source is used as the light source 1, a portion corresponding to the front surface of the LED is turned into a bright line. Or the equivalent of the front side of the LED-LED becomes a dark line. In this case, it is preferable that the shape of the light incident surface 31 is formed into a concave-convex shape such as an approximately circular arc shape, an approximately circular shape, an approximately trapezoidal shape, an approximately dome shape, or the like. By forming such a shape, it is possible to not only improve the efficiency of light entering the light guide 3 but also moderately diffuse light when the light is incident. As a result, the brightness can be made uniform even in the vicinity of the light incident surface 31 of the light guide 3. In the surface light source of the present invention, the thickness of the light guide 3 depends on the screen size. Usually 0.1 to 20 mm, suitably 0.1 to 15 mm, more preferably 〇.1 to 10 mm. The thickness of the light guide 3 is not necessarily required, and may be thinned away from the light incident surface 31 with a distance of k. Further, when the thickness of the light guide 3 is thinner than the thickness of the light source 1, the thickness of the vicinity of the light incident surface 31 of the light guide 3 may be increased in order to improve the light use efficiency, and the inclined portion may be formed only. The thinned light exits the portion of the face 3 2 . The light guide 3 used in the surface light source of the present invention is manufactured in the following manner. The light guide 3 of the present invention can be produced by a method such as injection molding or press printing. In addition, in the case of a thin light guide having a thickness of 0.8 mm or less or a large-area light guide having a screen size of 15 吋 or more, the linear groove 33 can be formed with high precision and reproducibility based on the high -23-200825468 礞. Or the viewpoint of the linear protrusions 34, t is suitably carried out by means of a stamping method. Further, in the case where the film thickness of the light guide 3 is 〇·8 / m or more and the screen size is 15 吋 or less, any one of injection molding and press printing can be suitably employed. In the case of the stamping method, the light guide 3 can be obtained by cutting into a desired shape after molding and honing the side portions. The resin constituting the light guide 3 is preferably an acrylic resin such as PMMA, a polycarbonate resin, a polyolefin resin such as polypropylene, polyisobutylene, polybutene or polymethylpentene, or a cycloolefin resin. A transparent resin material having a certain refractive index. [Reflection Sheet] The reflection sheet 4 is provided on the light non-emission surface 35 side of the light guide 3. The reflection sheet 4 reflects the light emitted from the light non-emission surface 35 of the light guide 3 to the light guide body. The characteristics, material, structure, and the like of the reflection sheet 4 are the same as those of the reflection sheet 2. [First optical film] The surface light source of the present invention is characterized in that a specific second optical film 5 is provided on the light incident surface 31 of the light guide 3. In the present invention, the first optical film 5 has a different direction diffusing property, and the direction in which the diffusing property in the different direction is the largest is approximately parallel to the longitudinal direction of the linear groove 33 or the linear protrusion 34. To configure it. In the present specification, "the so-called "differential diffusivity" means the use of an automatic variable angle luminosity g" relative reflectance system. The light emission angle distribution through which the light beam is transmitted from the side perpendicular to the film surface -24-200825468 is measured, and the diffusion mode of the transmitted light differs depending on the measurement direction. It is preferable to use a conventional device for the automatic variable angle photometer. For example, it is preferable to use an automatic variable angle photometer GP200 (manufactured by Murakami Color Technology Research Institute, Japan) or an automatic variable angle photometer having functions equivalent to or higher than this. Specifically, as shown in FIG. 8 , when the horizontal axis is the emission angle and the vertical axis is the amount of light, the amount of emission T 〇 ' is half the amount of light (T. / 2) The angle width is set to half-width d, which is different depending on the measurement direction. Here, the heterogeneous diffusivity is incident on the measured flaw from a smoother surface. Further, the term "the direction in which the divergence in the opposite direction is the largest" means that the half-width D of the transmitted light is the largest measurement direction. On the other hand, the "direction in which the different direction diffusing property is the smallest" means that the half width D of the transmitted light becomes the smallest measurement direction. In the case of the surface light source of the present invention, the direction in which the diffusivity of the first optical film 5 is maximized is arranged approximately in parallel with the longitudinal direction of the linear groove 3 3 or the linear protrusion 34 of the light guide 3. Thereby, the light emitted from the light guide 3 can be effectively utilized. As a result, a high-intensity surface light source can be formed. Here, the term "about parallel" means the direction in which the linear groove 3 3 or the linear protrusion 34 has a longitudinal direction (d 1 ) as shown in FIG. 9 and the diffusing property in the opposite direction of the first optical film 5 is the largest ( The angle 05 of d2) is 〇±15. Within. It is preferably 0±10. More preferably, it is 0±5. Within. Further, as described above, the adjacent linear grooves 3 3 or the linear protrusions 34 are curved or curved, and the main direction and the diffusion direction of the second optical film 5 are maximized. The angle is set to θ 5. -25- 200825468 The first optical film 5 is different from the half-width D1max of the transmitted light in the direction in which the diffusivity in the different direction when the light is incident from the normal direction, and when the light is incident from the normal direction. The ratio Dlmax/Dlmin of the transmitted light half-web Dlmin in the direction in which the direction diffusing property is the smallest is preferably 3 or more. The Dlmax/Dlmin$ parent is 5 or more, and the Dlmax/Dlmin is more preferably 7 or more. When Dlmax/Dlmin is less than 3, there is a case where the light emitted from the light exit surface 32 of the light guide 3 exceeds the necessary scattering and the brightness is lowered. By making Dlmax/Dlmin of the first precursor thin 5 5 or more, light emitted from the light exit surface 32 of the light guide 3 can be efficiently transmitted. As a result, it is possible to obtain a surface light source of a localized degree. Further, in the case of using the second optical film 6 to be described later, the effect of improving the brightness can be obtained. Further, the first optical film 5 is different in the case where light is incident from the normal direction. The half-width D 1 min of the transmitted light in the direction in which the direction diffusibility is minimized is preferably 10 or less. More preferably 7. Below, it is more preferably 5. the following. When Dlmin exceeds 10°, there is a case where the light emitted from the light exit surface 32 of the light guide 3 exceeds the necessary scattering and the brightness is lowered. In the surface light source of the present invention, Dlmin of the film 5 is made 10 by the younger brother. Hereinafter, the light emitted from the light exit surface 32 of the light guide 3 can be efficiently transmitted. As a result, it was seen that the surface light source of the locality was obtained. Further, in the case of using the second optical film 6 to be described later, the effect of improving the brightness can be obtained. Further, the total light reflectance of the first optical film 5 is preferably 45% or more. The total light reflectance is preferably more than 50%. Here, the total light reflectance refers to the amount of light transmitted through the film relative to the incident when the light is incident on the film using a light source (suitable as a standard light source, see ns -26-200825468. Z-8 720 (2000 edition)). The ratio of the amount of light. Further, in the case where the concavo-convex shape is formed on one side surface of the optical film 5, the ridge measured after being incident from the smoother surface is set as the total light reflectance. In the case where the concavo-convex shape is formed on both side faces of the optical film 5 or when both side faces are smooth, the larger 値 which is measured after the incident from both sides is measured is the total light reflectance. When the total light reflectance of the first optical film 5 is less than 45%, there is a case where the light emitted from the light guide 3 cannot be effectively utilized. In this way, by making

C 第1光學薄膜5之全部光線反射率成爲45 %以上，能夠作成高亮度之面光源。另外，第1光學薄膜5適宜之霧度爲70%以上。較宜之霧度爲7 5 %以上，更佳之霧度爲8 0 %以上。於此，所謂霧度係指射入光從光源（適宜爲標準光源、參照〗IS Z- 8 7 20 (2000年版））通過試料之期間，射入光束偏離2°以上所散亂透過之光量百分率（)，可以下列之關係式得到：C The total light reflectance of the first optical film 5 is 45% or more, and a high-luminance surface light source can be formed. Further, the first optical film 5 has a suitable haze of 70% or more. The preferred haze is above 75%, and the better haze is above 80%. Here, the term "haze" refers to the amount of light that is transmitted through the light source (suitable as a standard light source, referred to as IS Z-8 7 20 (2000 edition)), and the amount of light transmitted by the incident beam shifted by more than 2 degrees. The percentage () can be obtained by the following relationship:

Ht= lOOx ( Td/Tt ) 於此，Td係擴散反射率、Ί\係全部光線反射率，若將直線反射率設爲ΤΡ時，以下列之關係式表示：Ht= lOOx ( Td/Tt ) Here, the Td is the diffuse reflectance and the total light reflectance of the Ί\ system. When the linear reflectance is set to ΤΡ, the following relation is expressed:

Tt - Td + ΤΡ 還有，如凹凸形狀形成於光學薄膜5的單側表面之情形下，將從更平滑表面射入後而測出的値設爲霧度値。如凹凸形狀形成於光學薄膜5的兩側表面之情形或是兩側表面爲平滑之情形下，將從兩側表面射入後而測出的値中之 -27- 200825468 ；較大値設爲霧度値。若霧度未滿7 0 %時，由於無法充分進行光之擴散，將有作爲面光源的面內亮度分布或視野角特性變差之情形。於本發明之面光源中，藉由將第1光學薄膜5之霧度設爲7 0 %以上，能夠作成高亮度且具優越之視野角特性的面光源。另外，較宜之第1光學薄膜5的全部光線反射率爲45 %以上，且霧度爲7 0 %以上。更佳之全部光線反射率爲5 0 < %以上，且霧度爲7 5 %以上，特別理想之全部光線反射率爲50%以上，且霧度爲80%以上。藉由使第1光學薄膜5 之全部光線反射率成爲45%以上，且霧度爲70%以上，能夠作成高亮度之面光源。作爲第1光學薄膜5使用之薄膜，只要具有異方向擴散性的話，並無特別之限制。第1 0圖係顯示本發明之第1 光學薄膜例子之圖。如第10圖（a)，也可以爲使折射率不同於構成薄膜之樹脂的棒狀粒子（包含桿狀、紡錘狀）單向 , 配列於薄膜內部，而發現異方向擴散性。或是如第1 〇圖 (b )、（ c )之剖面爲曲面狀且單向配列成條紋狀之形狀’ 或是複數配列半面切割如第1 0圖（d)之紡錘形形狀的形狀等爲代表，也可以藉由將凹凸設置在薄膜之至少一側表面 .而發現異方向擴散性。或是也可以爲此等形狀之組合。剖面形狀可以爲如第10圖（b)之規則的，也可以爲如第1〇圖 (c )、（ d )之不規則的。基於能夠得到強的異方向擴散性’ 另外，其光擴散性的控制爲容易之觀點’此等形狀之中’ -28- 200825468 ^ 較宜使用至少藉由在薄膜之至少一側表面設置凹凸而發現異方向擴散性。將根據表面形狀而發現異方向擴散性的薄膜作爲第1 光學薄膜5使用之情形下，將第1光學薄膜5設置在導光體3上之際，較宜使設置凹凸之面位於觀察者方向之方式來裝載。因爲從面光源之射出分布的控制成爲容易之故。基於薄膜操作性或加工性等之觀點，第1光學薄膜5 的厚度FL1適宜爲30〜1000//m。較宜爲50〜700//m，尤以75〜500 # m特別理想。於此所謂薄膜的厚度FL1，如第 10圖U)所示，表面爲平滑之情形，係指如第1〇圖（b)所示，形狀僅設置在一側表面之情形，厚度FL 1則指從凸部之頂部起，直到未設置形狀之側表面爲止的厚度。另外，兩面設置凹凸形狀之情形，厚度FL 1係指從一側面之凸部頂部起，直到另一側面之凸部頂部爲止的厚度。如第1 〇圖（c )、 (d )，凹凸形狀視位置而高度不同的情形下，從凸部頂部 ( 起，到未設置形狀之側表面爲止的厚度平均値，設爲第1 光學薄膜5的厚度FL1。例如，第1光學薄膜5係如下方式而加以製造。第1 光學薄膜5係如第1 0圖（a)所示，使棒狀粒子含於薄膜內部的光學薄膜能夠利用下列方法加以製造：將已分散折射率不同的棒狀粒子之樹脂材料加工成片狀，至少沿著單軸方向拉伸此片材而使內部之棒狀粒子予以單向配列的方法；將已分散折射率不同的非相溶之熱可塑性樹脂加工成片狀 -29- 200825468 之際’拉伸分散於片材內部之熱可塑性樹脂後而作成棒狀，予以單向配列的方法等。樹脂材料、棒狀粒子、非相溶性樹脂之材質並未予以特別限定，只要爲折射率不同之組合的話，均能夠適合使用。另外，如第1 0圖（b ) 、（ d )所示，將凹凸形成於薄膜之至少一側表面以作成第1光學薄膜5，例如，能夠利用下列方法加以製造：一面控制薄膜表面上之粒子方向，並一面塗布含有棒狀粒子之塗布劑的方法；藉由發紋（hair 1 i n e )加工（刮擦薄膜表面的加工）而在表面上設置凹凸的方法；利用熱印壓法或光印壓法而在表面上設置凹凸的方法等。其中，基於能夠控制凹凸形狀或大小之觀點，尤以熱印壓法或光印壓法特別理想。所謂熱印壓法係指加熱已實施微細表面形狀之模具與基材之樹脂膜（基材薄膜），將模具按壓於基材薄膜，冷卻後進行脫模，以使模具表面上所實施的形狀轉印至基材薄膜上之手法。用於熱印壓法之樹脂可以爲熱可塑性樹脂或熱硬化性樹脂，適宜爲透過性高的樹脂。適合於熱印壓之樹脂，具體而言，能夠使用下列之樹脂：聚對苯二甲酸乙二醇酯、聚 2,6-萘二甲酸乙二醇酯、聚對苯二甲酸丙二醇酯、聚對苯二甲酸丁二醇酯等之聚酯系樹脂；聚乙烯、聚苯乙烯、聚丙烯、聚異丁烯、聚丁烯、聚甲基戊烯等之聚烯烴系樹脂；環烯烴系樹脂、聚醯胺系樹脂、聚醯亞胺系樹脂、聚醚系樹脂、聚酯醯胺系樹脂、聚醚酯系樹脂、 -30- 200825468 丙烯酸系樹脂、聚胺基甲酸酯系樹脂、聚碳酸酯系樹脂、聚氯乙烯系樹脂等。於此等樹脂之中，基於進行共聚合之單體種類的多樣性、及因此而使得材料物性之調整爲容易等理由之觀點，尤以從聚酯系樹脂、聚烯烴系樹脂、環烯烴系樹脂、聚醯胺系樹脂、丙烯酸系樹脂或此等之混合物所選出的熱可塑性樹脂爲主所構成者爲佳。此等之樹脂’若其結晶性爲高的，將會有於熱印壓法時之預熱步驟發生結晶化、白色化、成形性降低之情形。因此，適宜使用結晶性低的樹脂，較宜使用非結晶性樹脂。例如’水§曰系樹肖曰之情形，爲了使結晶性降低，藉由進行間苯二甲酸、環己烷二甲醇、雙酚A、2，6 -萘二甲酸、螺二醇、9,9’ -雙（4-羥基乙氧基苯基）蕗等之共聚合，能夠抑制樹脂之結晶化。所謂光印壓法，係一種如下所述之手法：將光硬化性樹脂塗布於基材薄膜上之後，將已實施微細表面形狀之模具按壓於光硬化性樹脂層之狀態下，或是將光硬化性樹脂塗布於模具上之後，於重疊基材薄膜之狀態下，從模具側或薄膜側照射紫外線等光線以使光硬化性樹脂硬化後而脫模，以使模具表面已實施的形狀轉印至樹脂上。適合於光印壓法之樹脂，只要爲根據電磁波作用而在分子內或分子間進行反應而交聯聚合之樹脂的話，任一種樹脂均能夠使用，於分子中能夠使用具有下列官能基等構造之樹脂：乙烯基、亞乙烯基、丙烯醯基、甲基丙烯醯基〔以下，合倂 -31 - 200825468 * 丙嫌酸基與甲基丙嫌釀基而稱爲（甲基）丙;(：希醯基。針對 (甲基）丙烯基、（甲基）丙烯酸酯等也呈現同樣之表現。〕、馬來酸酐縮亞胺基、環氧基等。基於交聯速度爲快的，此等官能基之中’適宜使用具有（甲基）丙烯醯基、環氧基、运氧丁院基之化合物。根據此等電磁波照射而可以進行交聯聚合之化合物，不僅適合使用於單體，也適合使用於已適當混合預聚物、寡聚物及/或單體之化合物。根據電磁波 r . 照射而可能進行交聯聚合之預聚物、寡聚物的例子，可列舉：不飽和二羧酸與多元醇之縮合物等不飽和聚酯類、聚酯（甲基）丙烯酸酯、聚醚（甲基）丙烯酸酯、聚醇（甲基）丙烯酸酯、三聚氰胺聚酯（甲基）丙烯酸酯陽離子聚合型環氧化物。另外，於不損及本發明效果之範圍內，也可以於第1 光學薄膜5中摻合各種添加劑，例如，抗氧化劑、耐熱安定劑、耐候安定劑、紫外線吸收劑、有機之易滑劑、顏料、 ^ 染料、塡充劑、抗靜電劑及成核劑等。〔第2光學薄膜〕本發明之面光源適宜於第1光學薄膜5上裝載第2光學薄膜6。於此，所謂第2光學薄膜6係指能夠變更從第1 光學薄膜5之射出角分布的片狀物。若使用第2光學薄膜 6時，能夠提高面光源之亮度、提高均勻度、控制視野角。其結果，能夠提高作爲面光源之品質。第2光學薄膜6之例子，可列舉··稜鏡片、具有等方向擴散性的擴散片（以 -32- 200825468 下’稱爲「等方向擴散性膜」）等。 (稜鏡片）第1 1圖係顯示於本發明中，能夠作爲第2光學薄膜6 使用之稜鏡片例子的圖。例如，稜鏡片能夠使用其形狀遍及面內爲一定之情形（第1 1圖（a ))、混雜各種高度的稜鏡之情形（第1 1圖（b ))、混雜各種稜鏡間距之情形（第 1 1圖（c ))、混雜各種稜鏡頂角物之情形（第1 1圖（d )) 及組合此等形狀之情形等。另外，如第i丨圖（e )，亦能夠使用稜鏡頂角成爲圓弧形之稜鏡片等。棱鏡片之稜鏡頂角03適宜爲80〜100。。03較宜爲 83〜97°’ 0 3更佳爲86〜94°。若稜鏡之頂角未滿80。或超過10(Γ時’將有從導光體3通過第1光學薄膜5的光之利用效率降低之情形。藉由將稜鏡片之頂角0 3設爲80〜100。之範圍內，能夠作成高的光利用效率之面光源。還有，當混雜不同的稜鏡頂角物之情形，則各自之頂角最好爲該範圍內。第2光學薄膜6使用稜鏡片之情形，棱鏡之長邊方向適宜設置在約，略平行於第1光學薄膜5之異方向擴散性成爲最大之方向。於此，所謂約略平行係意指如第12圖所示，稜鏡之長邊方向（d3)與第1光學薄膜5之異方向擴散性成爲最大之方向（d2 )的夾角0 6爲0± 15。以內。0 6 較宜爲〇±1〇°以內，0 6更佳爲0土5。以內。藉由設置在此方向，如後所述，能夠作成高的光利用效率之面光源。 -33- 200825468 稜鏡片之製法適宜利用光印壓法。將光硬化性樹脂塗布於基材薄膜上之後，將已形成稜鏡形狀的模具按壓於光硬化性樹脂層之狀態下，或是將光硬化性樹脂塗布於已形成稜鏡形狀的模具上之後，於重疊基材薄膜之狀態下，從模具側或薄膜側照射紫外線等光線，以使光硬化性樹脂予以硬化後而脫模，能夠將模具表面已實施的形狀形成於薄膜表面上。所用之樹脂能夠使用相同於第1光學薄膜5之 ^ 情形所列舉的樹脂。 η (等方向擴散性薄膜）所謂能夠作爲第2光學薄膜6使用之等方向擴散性膜係一種具有等方向擴散性之擴散片。於本說明書中，所謂「等方向擴散性」係指使光從第2光學薄膜6之法線方向射入時之擴散性成爲最大之方向上的透過光半値幅 D 2 m a X ’與使光從法線方向射入時之等方向擴散性成爲最小之方向上的透過光半値幅D2min之比D2max/D2min爲5以；. 下。D2max/D2min較宜爲3以下，更佳爲2以下，D2max/D2min 最好爲1 . 5以下。於此，「擴散性成爲最大之方向」、「擴散性成爲最小之方向」、「半値幅」之意義係相同於該第 1光學薄膜5中者。若半値幅之比D2max/D 2min超過5時，於面光源面內，將有均勻度降低，或是根據視野角而大幅改變亮度之可能性。於本發明之面光源中，將等方向擴散性膜作爲第2光學薄膜6使用之情形，藉由使其半値幅之比D2max/D2min成爲5以下，能夠作成具優越之視野角特 -34- 200825468 . 性、顯示特性的面光源。於此，D 2 m a X / D 2 m i η較1爲大、5以下之範圍的情形，較宜使第1光學薄膜5之異方向擴散性成爲最大之方向與’第2光學薄膜6之擴散性爲最大之方向成爲約略垂直。於此，所謂約略垂直係意指相鄰的線狀溝3 3或線狀突起3 4 之長邊方向’與第2光學薄膜6之擴散性成爲最大之方向的夾角Θ7爲90±15°以內。07較宜爲90±10。以內，更佳 f. 爲 90:1=5^以內。等方向擴散性膜係使光從法線方向射入時之擴散性成爲最小的方向上之透過光半値幅D2min適宜爲2〜50。。較宜爲3〜30°，更佳爲4〜15。。若D2min未滿2。時，將有導光體3之線狀溝3 3或線狀突起3 4被辨識，或是面光源內之均勻度將降低，根據視野角而大幅改變亮度的可能性。另外，若超過50°時，將有光之利用效率降低、面光源的亮度降低之情形。如此方式’藉由使用使其擴散性成爲最小 W- 之方向上的透過光半値幅D2min成爲2〜50。範圍內之等方向擴散性膜，能夠作成高亮度且具優越之視野角特性、均勻度的面光源。等方向擴散性膜之霧度適宜爲7 0 %以上。霧度較宜爲 7 5 %以上、霧度更佳爲8 0 %以上。還有，霧度係從較平滑面射入後而測出的値。若霧度未滿7 0 %時，由於無法充分擴散光，將有面光源的面內亮度分布或視野角特性變差之情形。於本發明之面光源中，藉由使第2光學薄膜6之霧 -35- 200825468 . 度成爲7 0 %以上，能夠作成高亮度且具優越之視野角特性的面光源。還有，霧度之定義係相同於該第1光學薄膜5 的霧度之定義。等方向擴散性膜係較宜其全部光線反射率爲5 0 %以上且霧度爲7 0 %以上。更佳全部光線反射率爲5 5 %以上且霧度爲75%以上，尤以全部光線反射率爲60%以上且霧度爲 80%以上特別理想。藉由使全部光線反射率成爲50%以上且霧度爲7 0 %以上，能夠作成高亮度且具優越之視野角特 Γ 性、均勻度的面光源。於第1 3圖，顯示具體之等方向擴散性膜的例子。例如，等方向擴散性膜可列舉：於薄膜內部含有構成薄膜之樹脂與折射率不同的球狀粒子者（第1 3圖（a ))、於薄膜表面形成含有球狀粒子之塗膜（第1 3圖（b ))、形成半面切割約略球形之約略圓頂狀物（第1 3圖（c ))等，以使凹凸形狀形成於薄膜之至少一側表面者，或組合此等之物 1) 等。藉由作成如此之形狀，能夠發現等方向擴散性。此等之薄膜或凹凸形狀的剖面形狀可以爲規則的，也可以爲不規則的。能夠得到高的擴散性，另外，基於其光擴散性的控制爲容易之觀點，更佳係將凹凸設置在薄膜之至少一側表面的等方向擴散性膜。基於薄膜的操作性或加工性等之觀點，等方向擴散性膜的厚度FL2適宜爲30〜1000//m，較宜爲50〜700//m，尤以75〜5 00 // m特別理想。於此薄膜的厚度FL2，如第13 -36- 200825468 - 圖（a )所示，表面爲平滑之情形，係指其厚度，如第1 3圖 (b )所示，形狀僅設置在一側表面之情形，係指從凸部之頂點起，直到未設置形狀之側表面爲止的厚度。另外，形狀設置在兩面之情形，則係指從一側表面之凸部頂點起，直到另一側表面之凸部頂點爲止的厚度。如第1 3圖（c )所示，依位置而定，高度不同之情形下，則以其平均値作爲第2光學薄膜6的厚度FL2。還有，此薄膜的厚度也相同於該稜鏡片。 Γ:: 如第1 3圖（a )所示，於薄膜內部具有等方向擴散性之等方向擴散性膜能夠藉由將已使折射率不同的約略球狀粒子分散的樹脂材料加工成片狀後而得到。另外，基於使機械強度得以提高之觀點，較宜進行此片材之單軸或雙軸的拉伸。另外，將平面安定性、尺寸安定性賦與已進行單軸或雙軸拉伸之薄膜，進一步必要時，爲了徹底消除於折射率 Li 不同的約略球狀粒子與樹脂之間生成的空隙（void)，接著，藉由在拉幅器內進行熱處理（熱固定），熱處理後，均勻地徐冷之後，冷卻至室溫附近，以製造已將球狀粒子分散於薄膜內部的等方向擴散性膜。另外，等方向擴散性膜係如第1 3圖（b )所示，使凹凸形狀形成於薄膜之至少一側表面後而發現等方向擴散性之方法，可列舉：將含有微粒之塗劑塗布於薄膜表面的方法；利用熱印壓法或光印壓法以將凹凸設置在表面的方法。針 -37- 200825468 • 對依熱印壓法或光印壓法所進行之方法，能夠利用相同於第1光學薄膜5之製法的方法加以製作。於不損及本發明效果之範圍內，也可以在用於本發明之第2光學薄膜6中摻合各種添加劑，例如，抗氧化劑、耐熱安定劑、耐候安定劑、紫外線吸收劑、有機之易滑劑、顏料、染料、塡充劑、抗靜電劑及成核劑等。〔高亮度化〕 g 本發明之面光源係將具有該異方向擴散性之薄膜作爲 I ' 第1光學薄膜5使用，藉由使此擴散性成爲最大的方向與導光體3之線狀溝3 3或線狀突起3 4的方向約略平行地予以配置，可期望高亮度化。另外，進一步藉由配置作爲第 2光學薄膜6之特定薄膜，能夠作成習知面光源無法達成的高亮度、具優越之視野角特性、均勻度的面光源。針對其詳細內容加以說明。首先，針對期求高亮度化之機構加以說明。第1 4圖係 ί 顯示稜鏡片之光線透過特性的圖。從法線方向附近射入稜鏡片之光（λ i 1 )係於稜鏡/空氣界面重複進行全反射，結果，返回法線之相反方向而不透過稜鏡片。若使用反射片而進行返回光之反射的話，能夠再利用。但是，若重複反射的話，因爲光線將失活等，成爲光線之損失。接著，以大的角度射入稜鏡片之光（λ i 3 )，於片材表面之反射爲大的。另外，即使射入，也於稜鏡/空氣界面，朝法線方向的相反方向進行折射而成爲迷光。因此，成爲 -38- 200825468 - 光線之損失。另一方面，於射入角± 3 0 °附近射入的光（λ丨2 )能夠於射入面與棱鏡/空氣界面分別折射’而在法線方向將有效地偏光。因此，爲了使用稜鏡片予以高亮度化，增多λ i 2 成分爲重要的。不使用棱鏡片的構造之情形’無法如使用棱鏡片之情形般的因表面上折射所造成之指向法線方向。因此，爲了 p 予以局売度化，以使從導光體3之射出角分布多數射向法線方向爲必要的。亦即，爲了期求高亮度化，控制光學薄膜之種類與從導光體3之射出特性爲重要的。具體而言，使用稜鏡片作爲第2光學薄膜之情形下，增加於射入角± 3 〇。附近進行射入的光將成爲重要的。另外，不設置第2光學薄膜之情形，將等方向擴散性片作爲第2光學薄膜使用之情形下，增加法線方向之光將成爲重要的。基於上述之想法，針對使本 ^ 發明之面光源予以高亮度化之機構，使用第1 5〜1 7圖加以說明。本發明之面光源並不受此等機構所限定。第1 5圖係示意說明傳播於導光體內，進行射出之光的圖。第15圖（a)係示意顯示傳播於導光體3內之光的圖。於此圖之例子中，導光體3係於光射出面3 2之相反側形成三角形之線狀溝3 3。從光射入面3 1射入的光，具有平行於導光體3表面，且不照射於光射出面3 2與光非射出面3 5地進行傳播的光；及於導光體3之光射出面3 2或光非射出面 -39- 200825468 . 3 5上重複進行全反射，傳播於導光體3內的光。此等於導光體3內的光之中，撞擊線狀溝3 3的光係藉由在溝3 3之表面反射以改變其行進方向。其結果，成爲以角以下射入光射出面3 2，射向導光體3外（第15圖 λρΐ、λρ2、λ ρ 3) 〇第1 5圖（b )〜（g )係示意顯示衝撞於線狀溝3 3 狀突起34之光的光程之圖。於第15圖（b )〜（g )之 f 係線狀溝3 3情形之例子，線狀突起3 4之情形也爲相[1 另外，第1 5圖（b )〜（d )係位於已設置在導光體之溝的光源側之斜面，與垂直於該光源1之直線的夾角 =45 °之情形的例子；第1 5圖（e )〜（g )係位於已設導光體之線狀溝的光源側之斜面，與垂直於該光源1 線的夾角 0 1 = 40。之情形的例子。第1 5圖（b )、（ e 約略平行於導光體面地衝撞於線狀溝3 3的光之例子；圖（d )、（ g )係從光非射出面3 5衝撞於線狀溝3 3的 / 例子；第15圖（c ) 、（ f )係從光非射出面3 5反射後撞於線狀溝33的光之例子。還有，θ 1爲42.5〜50°之下，能夠認爲相同於0 1 = 45 °之情形的原理；0 1爲 42.5°之情形下，能夠認爲相同於θ 1二40°之情形的原另外，線狀突起3 4之情形下，Θ 2也相同於該0 1。 θ 1 = 45。之情形下，如第15圖（b)所示，撞擊約略於導光體3表面之線狀溝3 3或線狀突起3 4的光（λ 係於其斜面進行全反射，射向導光體3之光射出面3 2 傳播線狀臨界 (a)' 或線例子 3的。線狀 Θ 1 置在之直。係第15 光之而衝情形 20〜理。平行 Pi ) 的約 -40- 200825468 略法線方向（λ ο 1 )。但是，由於實際上成爲相鄰接的線狀溝3 3之陰影，故循著此路徑之光量爲少的。因此，如第 15圖（〇所示，大部分之光係從光射出面32側撞擊線狀溝 33，或是如第15圖（d)所示，從光非射出面35側反射後而撞擊線狀溝33。如第15圖（c)所示，從光射出面32側撞擊線狀溝3 3的光λ p2係於其斜面返回光源1側之方式來進行全反射。另外，如第15圖（d)所示，從光非射出面35側反射後而撞擊線狀溝3 3的光λ p 3係於其斜面全反射至與光源1側相反側之方向。如此方式，經由斜面所反射的光係相反於光射出面3 2之法線方向，折射後而射出（λ 〇2、 λ 〇3 )。即，於θ 1 = 45。之情形下，能夠使許多光線射向偏離法線方向之方向的傾斜方向。另一方面，於0 1 = 40。之情形下，如第15圖（e)所示，撞擊約略平行於導光體3表面之線狀溝3 3的光（λ p 1 )係於其斜面進行全反射，射向導光體3之光射出面3 2的約略法線方向（λ ο 1 )。但是，由於實際上成爲相鄰接的線狀溝3 3或線狀突起3 4之陰影，故循著此路徑之光量爲少的。因此’如第1 5圖（f )所示，大部分之光係從光射出面3 2 側撞擊線狀溝3 3，或是如第1 5圖（g )所示，從光非射出面 3 5撞擊線狀溝3 3。如第1 5圖（f )所示，從光射出面3 2側撞擊線狀溝3 3的光λ p2係於其斜面返回光源1側之方式來進行全反射，相反於光射出面3 2之法線方向，折射後而射出（λ 〇 2 )。但是，此射出角0 〇 2較0 1二4 5。時爲小。 -41 - 200825468 ; 另外’如第1 5圖（2 )所示，從光非射出面3 5側反射後而撞擊線狀溝3 3的光λ p 3係於其斜面全反射至與光源1側相反側之方向。經由斜面所反射的光係相反於光射出面3 2 之法線方向’折射後而射出（λ 〇 3 )。此射出角0 〇 3較0 1 =45°時爲大。θ 1二40。之情形，反射光射入導光體3之光射出面32的角度較Θ 1=45。時爲大。因此’進行全反射後而返回導光體3內，再度傳播於 (、導光體3內之光將增多。亦即，於0 1 = 4 0。之情形下，能夠使許多光線射向法線方向。根據上述，得知：若控制位於導光體上所設置之線狀溝光源側之斜面，與垂直於該光源1之直線的夾角0 1的話’便能控制從導光體3之光射出面3 2所射出的光。具體而言，θ 1爲42.5〜45。之情形下，能夠使多數光線斜向射出；0 1爲20〜42.5°之情形下，能夠使多數光線射向法線方向。 { 第1 6圖係於本發明之面光源中，針對來自導光體3之光射出面3 2之射出光的射出角分布之例子加以說明之圖。還有，於第1 6圖之例子中所說明之射出角分布係如第 2圖（a )所示，於二個光源1及反射板2夾住導光體3且相對的形態之面光源中，顯示來自導光體3的光射出面3 2之中央部的射出角分布之一例。導光體3係在與光射入面3 1 平行方向，以使三角形之線狀溝3 3形成於光非射出面3 5 側情形之例子。還有，第1 6圖（a ) 、（ b )係0 1 = 45 °之 -42- 200825468 情形，第1 6圖（c ) 、（ d )係0 1 = 4 0 °之情形的射出角分布。第1 6圖（a )、（ c )係垂直於線狀溝3 3之長邊方向的面內（以下，簡稱爲垂直於線狀溝3 3之表面）的射出角分布。第1 6圖（b ) 、（ d )係平行於包含光射出面3 2法線方向之線狀溝3 3之長邊方向的面內（以下，簡稱爲平行於線狀溝3 3之表面）的射出角分布。第1 7圖係顯示從如第2圖（a )所示之將異方向擴散膜或等方向擴散性膜裝載於二個光源1及反射板2夾住導光體3且相對形態之面光源的導光體3上時之中央部的射出角分布之一例。還有，第17圖（a) 、（b)係01=45。之情形，第1 7圖（c ) 、（ d )係0 1 = 4 0。之情形的射出角分布。第1 7圖（a )、（ c )係垂直於線狀溝3 3之面內的射出角分布。第1 7圖（b ) 、（ d )係平行於線狀溝3 3之面內的射出角分布。本發明面之光源，當作成導光體3之線狀溝3 3之光源 1側斜面的角度0 1 = 4 5 °之情形，如第1 6圖（a )所示，在垂直於線狀溝3 3之面內，能夠使多數光射向± 3 〇。方向附近。另一方面，平行於線狀溝3 3之面內，成爲於土 4 0。方向附近具有極大點之寬廣的射出角分布（第1 6圖（b ))。亦即，藉由將線狀溝3 3之光源1側斜面的角度θ 1控制成 4 5。，垂直於線狀溝3 3之面內，能夠使含有多數適合於稜鏡片方向之光予以射出。另一方面，於其他之面內（例如，平行於線狀溝3 3之面內），多數光射向適合於稜鏡片方向 -43- 200825468 以外之方向。因而，若能夠使其之光射向稜鏡片之適當方向的話，使能夠達成高亮度化。於具有該射出角分布之導光體3的射入面32上，於第 1 7圖（a )、（ b )顯示設置異方向擴散膜或等方向擴散性膜時之射出角分布。使用等方向擴散性膜之情形，使光予以均等擴散，紊亂了從導光體3之射出角分布。亦即，對於來自導光體3之射出光係於射出角±30°附近爲大的，再者，若通過等方向擴散性膜時，將減少射出角±30°附近之光 r \ 量。因此，由於適合於稜鏡片之方向的射出光量將減少，效率將降低而不佳。另一方面，若使其擴散性成爲最大之方向與線狀溝3 3之長邊方向約略平行之方式來配置具有強異方向擴散性的異方向擴散膜時，不會擴散至垂直於線狀溝3 3之方向（第1 7圖（a ))，而是僅使方向平行於線狀溝3 3之長邊方向的光予以擴散（第17圖（b ))。其結果，不會紊亂垂直於線狀溝3 3之面內的射出角分布，而是 j 平行於線狀溝3 3之面內，能夠將射出的光集中於光射出面 3 2之法線方向。藉此，使適合於棱鏡片角度之光予以增大將成爲可能的。亦即，將稜鏡片作爲第2光學薄膜6使用之情形下，能夠予以高亮度化。根據如上所述，將棱鏡片作爲第2光學薄膜6使用之情形下，可得知：位於導光體3所設置之線狀溝3 3的光源 1側之斜面，與垂直於該光源1之直線的夾角；或是位於導光體3所設置之線狀突起34的光源1相反側之斜面與垂 -44- 200825468 ，直於該光源1之直線的夾角可以爲42.5〜50。。另外，於本發明之面光源中，設定導光體3之線狀溝 33之光源1側斜面的角度0 1 = 40。之情形係如第16圖（c ) 所示，垂直於線狀溝3 3面內之情形，能夠使多數光射向〇。方向附近。另一方面，平行於線狀溝3 3面內之情形，多數光射向±40°方向附近（第16圖（d))。若將異方向擴散膜設置在此導光體上時，在垂直於線狀溝3 3的方向之情形，能夠射出多數含有0°方向之光（第17圖（c))。另外，於 f 其他面內（例如，平行於線狀溝3 3之面內）之情形，若設置異方向擴散膜時，能夠將射向0 °方向以外的光朝向光射出面32之法線方向（第17圖（d ))。另一方面，若使用等方向擴散性膜時，相較於異方向擴散膜，不論在垂直於線狀溝3 3之方向，或是在其他面內（例如，平行於線狀溝 33之面內），均能夠使射向0°方向以外之光朝向光射出面 3 2之法線方向（第17圖（c ) 、（ d ))。亦即，得知藉由 ^ 將異方向擴散膜作爲第1光學薄膜5使用，以使線狀溝3 3 的光源1側之斜面角度控制於4 0 °，法線方向之光射出將增加。如此方式，若位於導光體3所設置之線狀溝3 3的光源 1側之斜面與垂直於該光源1之直線的夾角，或是位於導光體3所設置之線狀突起3 4的光源1相反側之斜面與垂直於該光源1之直線的夾角爲2 0〜4 2 · 5。時，法線方向之光的射出將增加。因而，若爲此條件的話，得知即使不使用第 -45- 200825468 . 2光學薄膜6之情形，也可以得到高亮度之面光领另外，如上所述，將光擴散片作爲第2光學用之情況，若法線方向之光爲多的話，可期望面亮度化。亦即，此情形下，位於導光體3所設置 3 3的光源1側之斜面與垂直於該光源1之直線的是位於導光體3所設置之線狀突起34的光源1相面與垂直於該光源1之直線的夾角也可以爲20〜 p 〔面光源〕具有該構造之本發明的面光源，面內亮度之適宜爲65%以上。較宜爲70%以上，更佳爲75% 以80%以上特別理想。此處，所謂亮度之均勻度用色彩亮度計，於5吋以上的大畫面尺寸之情形視野角1°測定顯示於第18圖（a)之面光源內25 時；於5吋以下的畫面尺寸之情形，以測定視野定顯示於第1 8圖（b )之面光源內9點的亮度時，、最大亮度Bmax及最低亮度Bmin，根據下式所計還有，使用於均勻度測定之色彩亮度計能夠使用例如，適宜使用 BM-7/FAST ( Topcon (股份）製級以上者。 U= Bmin/Bmaxx 1 00 於本發明之面光源中，藉由將均勻度U設ί 上’能夠得到良好之顯示特性。另外，本發明之面光源係畫面上下方向之視薄膜6使光源之局之線狀溝夾角，或反側之斜 42.5° 。均勻度 U 以上，尤 U，係使，以測定點的亮度角 0.21ϋ 從各自之算之値。習知者。 )或同等爵65%以野角或左 -46- 200825468 : 右方向之視St角中任一者適且爲20。以上，畫面左右方向之視野角較宜爲20°以上。更佳爲25。以上，最好爲3〇。以上。此處’所g胃視野角係指使用色彩売度計，每隔2。分別測定畫面上下方向±80°之範圍、或是畫面左右方向±8〇。之範圍的射出角分布’橫軸設爲射出角、縱軸設爲亮度而進行面光源中央部之作圖時，相對於法線方向之亮度B()，一半亮度（B。/ 2)時之角度寬（半値幅W)。藉由使本發明面光 ^ 源的視野角設爲20°以上之範圍，用途不受限制，能夠作爲可利用於廣泛用途之面光源。還有，用於視野角測定之色彩売度計能夠使用習知者。例如，適宜使用 BM-7/FAST (Top con (股份）製）或同等級以上者。本發明之面光源並不受該構造所限定，於不失去本發明效果之範圍內，將其他薄膜***第2光學薄膜6之上、導光體3/第1光學薄膜5之間、或第1光學薄膜5/第2光學薄膜6之間等也爲可能的。組合其他薄膜也爲可能的。 t 能夠使用之薄膜的例子，可列舉：其他之擴散膜、稜鏡片、視野控制膜、反射型偏光板、亮度提高薄膜、偏光分離片、色調補償薄膜等。例如，其使用例係進一步將擴散膜配置於第2光學薄膜6上，顯示品質將提高，能夠得到更進一步之亮度提高效果。另外，若配置反射型偏光板使其偏光軸與液晶顯示裝置之偏光軸相一致之方式時，便可能提高光利用效率，能夠進一步達成咼壳度化。基於具優越之光利用效率的高亮度且廣視野角視野之 -47- 200825468 觀點’本發明之面光源較習知之面光源更爲優異，能夠適用於行動電話、電子筆記本、筆記型PC、監視器、TV、各種顯示媒體等從背面照射液晶顯示元件之用途。本發明之液晶顯示裝置係以裝載該面光源爲特徵。若使用本發明之面光源的話，能夠得到高亮度且具優越之視野角特性、均勻度之清晰液晶顯示裝置。〔特性之評估方法〕本發明之特性的評估方法係利用以下揭示之方法。若測定裝置爲可以得到與以下之評估方法同等級或更佳之結果的話，也可以使用其他之裝置。 A .全部光線反射率、霧度使用日本Suga試驗機股份公司製之全自動直接讀取霧度電腦HGM-2DP，測定薄膜之全部光線反射率、霧度。於薄膜面內，變更5處位置後而進行測定，以其平均値而作爲全部光線反射率、霧度。還有，光源係使用標準光源（參照 JIS Z-8720 ( 2000 年度））。還有，全部光線反射率與霧度當兩者皆於光學薄膜單側面上形成凹凸形狀之情形下時，則從更平滑面射入後而測出之値。另外，如凹凸形狀形成於光學薄膜兩側表面之情形，或是光學薄膜的兩側表面爲平滑之情形’則爲從兩側表面射入後而測出之値中的較大値。 B.半値幅 Dmax、Dmin、比 Dmax/Dmin 利用自動變角光度計G P 2 0 0 (日本村上色彩技術硏究 -48- 200825468 所製），從垂直於薄膜面之方向而使光束射入，測定每1° 之相對反射率後而求出射出角分布。從所得到的射出角分布之結果，求出擴散性成爲最大之方向的半値幅D m a X與擴散性成爲最小之方向的半値幅 Dmiii。於薄膜面內，變更5處位置後而同樣進行測定，分別求出半値幅Dmax、Dmin之平均値，從此等平均値而求出半値幅之比Dmax/Dmin。還有，不論半値幅Dmax、Dnnn中任一種均是從平滑面射入後而測出。 C .導光體形狀評估使用三次元形狀測定器NH-3SP(日本三鷹光器（股份）製），於倍率1 00倍（短焦點）、掃描間隔0.1 // m，測定導光體之線狀溝33的深度H1或線狀突起34的高度H2、光源1側之傾斜角θ 1或0 2、導光體3之光射出面3 2的表面粗糙度Ra。 D.薄膜剖面構造於切開薄膜之剖面、蒸鍍鉑-鈀之後，利用日本電子（股份）製之電場放射掃描型電子顯微鏡” JTSM-6700F”以拍攝照片’進f了剖面観察。於薄0吴面內，變更5處位置後而進行測定。從各自之剖面照片，求出薄膜表面之凹凸形狀（凸部的高度Η、寬度S、縱橫比H/S )薄膜內部之分散狀態（分散徑R )，以其平均値作成薄膜表面之凹凸形狀（凸部的高度Η、寬度S、縱橫比H/S )薄膜內部之分散狀態（分散 -49- 200825468 _ 徑 R)。 Ε·亮度、均勻度、視野角配置光源1、” Lumirror” （註冊商標）E6 S V ( Tor ay (股份）製）作爲反射板2、導光體3、將” L u m i r r o r ” （註冊商標）E6SL ( Tor ay (股份）製）作爲於導光體3下側之反射片4、於導光體3上側第1光學薄膜5、第2光學薄膜 6，製作面光源。10分鐘後，使用色彩亮度計BM-7/FAST (Topcon (股份）製），於5吋以上的大畫面尺寸之情形， r ' 以測定視野角1°測定顯示於第18圖（a)之面光源內25點的亮度時；於5吋以下的畫面尺寸之情形’以測定視野角〇. 2。測定顯示於第1 8圖（b )之面光源內9點的亮度。利用以下之基準判定所得到的中心亮度： 1 )將稜鏡片作爲第2光學薄膜使用之時 1 7吋之情形中心亮度爲6800cd/m2以上之情形：A ^ i 中心亮度爲6700cd/m2以上、未滿6800cd/m2之情形：Tt - Td + ΤΡ Further, in the case where the uneven shape is formed on one side surface of the optical film 5, the enthalpy measured after the incident from the smoother surface is set is haze 値. If the uneven shape is formed on both side surfaces of the optical film 5 or the both surfaces are smooth, the 値之 -27-200825468 which is measured after being incident from both side surfaces; Haze is awkward. When the haze is less than 70%, the in-plane luminance distribution or the viewing angle characteristic of the surface light source may be deteriorated because the light diffusion cannot be sufficiently performed. In the surface light source of the present invention, by setting the haze of the first optical film 5 to 70% or more, it is possible to produce a surface light source having high brightness and excellent viewing angle characteristics. Further, it is preferable that the total light reflectance of the first optical film 5 is 45% or more and the haze is 70% or more. Better all light reflectivity is 5 0 <% or more, and the haze is 75% or more, and particularly preferably all of the light reflectance is 50% or more, and the haze is 80% or more. When the total light reflectance of the first optical film 5 is 45% or more and the haze is 70% or more, a high-luminance surface light source can be produced. The film used as the first optical film 5 is not particularly limited as long as it has a divergence in the opposite direction. Fig. 10 is a view showing an example of the first optical film of the present invention. In the case of Fig. 10 (a), rod-shaped particles (including a rod shape or a spindle shape) having a refractive index different from that of the resin constituting the film may be arranged in the inside of the film to find the diffusivity in the opposite direction. Or, as shown in Fig. 1 (b) and (c), the cross section is curved and unidirectionally arranged in a stripe shape or the shape of a plurality of half-face cuts such as the shape of the spindle shape of Fig. 10 (d) is Alternatively, the unevenness may be provided on at least one side surface of the film. And found in the opposite direction of diffusivity. Or you can also combine these shapes. The cross-sectional shape may be as defined in Fig. 10(b), or may be irregular as in Figs. 1(c) and (d). It is preferable to use at least one surface of the film to provide unevenness by controlling the diffusivity of the light in the opposite direction. It was found to be diffuse in the opposite direction. When a film having different diffusibility in the surface shape is used as the first optical film 5, when the first optical film 5 is placed on the light guide 3, it is preferable that the surface on which the unevenness is provided is located in the direction of the observer. The way to load. Because the control of the emission distribution from the surface light source is easy. The thickness FL1 of the first optical film 5 is preferably 30 to 1000 / / m from the viewpoint of film workability, workability, and the like. It is preferably 50 to 700 / / m, especially 75 to 500 # m is particularly desirable. Here, the thickness FL1 of the film is as shown in FIG. 10(U), and the surface is smooth, as shown in FIG. 1(b), the shape is only provided on one side surface, and the thickness FL 1 is Refers to the thickness from the top of the convex portion until the side surface of the shape is not provided. Further, in the case where the uneven shape is provided on both sides, the thickness FL 1 means the thickness from the top of the convex portion of one side surface to the top of the convex portion of the other side surface. In the case of the first and second figures (c) and (d), when the uneven shape is different in height depending on the position, the thickness average 値 from the top of the convex portion to the side surface on which the shape is not provided is set as the first optical film. For example, the first optical film 5 is produced as follows. The first optical film 5 is as shown in Fig. 10 (a), and the optical film in which the rod-shaped particles are contained in the film can be used as follows. The method comprises the steps of: processing a resin material having rod-shaped particles having different refractive indexes into a sheet shape, stretching the sheet at least along a uniaxial direction, and arranging the inner rod-shaped particles in one direction; When a non-compatible thermoplastic resin having a different refractive index is processed into a sheet form -29-200825468, a method of forming a rod shape by stretching a thermoplastic resin dispersed in a sheet, and arranging it in one direction, etc. The material of the rod-like particles and the incompatible resin is not particularly limited, and any combination of refractive indexes can be suitably used. Further, as shown in Figs. 10(b) and (d), irregularities are formed. Film The at least one surface is formed as the first optical film 5, and can be produced, for example, by a method of controlling the direction of the particles on the surface of the film and applying a coating agent containing the rod-like particles on one side; 1 ine ) a method of processing (scratching a surface of a film) and providing irregularities on the surface; a method of providing irregularities on the surface by a hot stamping method or a photolithography method, etc., wherein the shape or size of the unevenness can be controlled based on The viewpoint of hot stamping or photolithography is particularly desirable. The hot stamping method refers to heating a resin film (substrate film) of a mold and a substrate having a fine surface shape, and pressing the mold against the substrate. The film is cooled and then demolded to transfer the shape on the surface of the mold to the substrate film. The resin used for the hot stamping method may be a thermoplastic resin or a thermosetting resin, which is suitable for permeability. High resin. Resin suitable for hot stamping. Specifically, the following resins can be used: polyethylene terephthalate, polyethylene-2,6-naphthalate, poly Polyester resin such as propylene carbonate or polybutylene terephthalate; polyolefin resin such as polyethylene, polystyrene, polypropylene, polyisobutylene, polybutene or polymethylpentene Cycloolefin resin, polyamine resin, polyimide resin, polyether resin, polyester amide resin, polyether ester resin, -30- 200825468 Acrylic resin, polyaminocarboxylic acid An ester resin, a polycarbonate resin, a polyvinyl chloride resin, etc. Among these resins, the diversity of the types of monomers to be copolymerized and the adjustment of material properties are easy. In particular, a thermoplastic resin selected from a polyester resin, a polyolefin resin, a cycloolefin resin, a polyamide resin, an acrylic resin or a mixture thereof is preferred. If the resin is high in crystallinity, the preheating step in the hot stamping process may be crystallized, whitened, and the formability may be lowered. Therefore, it is preferable to use a resin having low crystallinity, and it is preferred to use a non-crystalline resin. For example, in the case of 'water § 树树曰 ,, in order to reduce crystallinity, by using isophthalic acid, cyclohexane dimethanol, bisphenol A, 2,6-naphthalenedicarboxylic acid, spirodiol, 9, The copolymerization of 9'-bis(4-hydroxyethoxyphenyl)anthracene or the like can suppress the crystallization of the resin. The photolithography method is a method in which a photocurable resin is applied onto a base film, and a mold having a fine surface shape is pressed against the photocurable resin layer, or light is applied. After the curable resin is applied to the mold, the film is superimposed on the mold side or the film side, and light is irradiated from the mold side or the film side to cure the photocurable resin, thereby releasing the mold to transfer the shape of the mold surface. To the resin. The resin suitable for the photolithography method can be used as long as it is a resin which is crosslinked and polymerized by intramolecular or intermolecular reaction depending on the action of electromagnetic waves, and any of the following functional groups can be used in the molecule. Resin: vinyl, vinylidene, acryl fluorenyl, methacryl fluorenyl [hereinafter, conjugated-31 - 200825468 * propyl sulphonate and methyl propyl sulphonate is called (methyl) propyl; (: The same is true for (meth)acryl-based, (meth) acrylate, etc.], maleic anhydride, imino group, epoxy group, etc. Among the functional groups, a compound having a (meth) acryl fluorenyl group, an epoxy group, or an oxybutyl group is suitably used. A compound which can be crosslinked and polymerized according to such electromagnetic wave irradiation is not only suitable for use in a monomer but also It is suitable for use in compounds which have been properly mixed with prepolymers, oligomers and/or monomers. Examples of the prepolymer and the oligomer which may be crosslinked and polymerized by irradiation include unsaturated polyesters such as condensates of unsaturated dicarboxylic acids and polyhydric alcohols, polyester (meth) acrylates, and polyethers. (Meth) acrylate, polyalcohol (meth) acrylate, melamine polyester (meth) acrylate cationically polymerized epoxide. Further, various additives such as an antioxidant, a heat stabilizer, a weather stabilizer, an ultraviolet absorber, an organic slip agent, and the like may be blended in the first optical film 5 without departing from the effects of the present invention. Pigments, ^ dyes, chelating agents, antistatic agents and nucleating agents. [Second optical film] The surface light source of the present invention is suitable for mounting the second optical film 6 on the first optical film 5. Here, the second optical film 6 is a sheet-like object in which the distribution angle of the first optical film 5 can be changed. When the second optical film 6 is used, the brightness of the surface light source can be improved, the uniformity can be improved, and the viewing angle can be controlled. As a result, the quality as a surface light source can be improved. Examples of the second optical film 6 include a ruthenium sheet, a diffusion sheet having an isotropic diffusibility (referred to as "an isotropic diffusible film" under -32-200825468), and the like. (Bristles) Fig. 1 is a view showing an example of a ruthenium which can be used as the second optical film 6 in the present invention. For example, the bracts can be used in a case where the shape is constant in the plane (Fig. 1 (a)), the case where the heights are mixed (Fig. 1 (1) (b)), and the various interlaces are mixed. (Fig. 1 (c)), the case where various kinds of domes are mixed (Fig. 11 (d)), and the case where these shapes are combined. Further, as in the case of (i), it is also possible to use a cymbal having a dome angle and a circular arc shape. The dome angle 03 of the prism sheet is suitably 80 to 100. . 03 is preferably 83 to 97°' 0 3 and more preferably 86 to 94°. If the top corner of the skull is less than 80. Or when it exceeds 10 (the case where there is a case where the efficiency of light passing through the first optical film 5 from the light guide 3 is lowered. By setting the apex angle 0 3 of the cymbal to 80 to 100, A surface light source having a high light utilization efficiency. Further, when a different dome angle is mixed, the respective apex angles are preferably within the range. The second optical film 6 is in the case of a ruthenium, and the prism is used. The longitudinal direction is preferably set to be approximately parallel to the direction in which the diffusivity in the opposite direction of the first optical film 5 is maximized. Here, the approximately parallel system means the longitudinal direction of the crucible as shown in Fig. 12 (d3) The angle θ of the direction (d2) in which the diffusivity in the opposite direction of the first optical film 5 is the maximum is 0±15. Within 0 6 is preferably within ±1〇°, and 0 6 is preferably 0 soil 5 By setting it in this direction, as will be described later, it is possible to produce a high light utilization efficiency surface light source. -33- 200825468 The method of preparing the ruthenium film is suitable for the photolithography method, and the photocurable resin is applied to the substrate. After the film is formed, the mold having the shape of the crucible is pressed against the photocurable resin layer. In the state in which the photocurable resin is applied to a mold having a crucible shape, the light is cured by irradiating light such as ultraviolet rays from the mold side or the film side in a state in which the base film is superposed. After the mold is released, the shape of the surface of the mold can be formed on the surface of the film. The resin used can be the same as that exemplified in the case of the first optical film 5. η (equal diffusing film) The isotropic diffusing film used in the second optical film 6 is a diffusing film having an isotropic diffusivity. In the present specification, the term "equal diffusing property" means that light is incident from the normal direction of the second optical film 6. The diffusion ratio becomes the ratio of the transmitted light half-web D 2 ma X ' in the largest direction and the transmitted light half-width D2min in the direction in which the direction of diffusivity is minimized when the light is incident from the normal direction D2max/D2min For 5; under. D2max/D2min is preferably 3 or less, more preferably 2 or less, and D2max/D2min is preferably 1. 5 or less. Here, "the direction in which the diffusibility is the largest", the direction in which the diffusibility is the smallest, and the meaning of the "half-width" are the same as those in the first optical film 5. If the half-twist ratio D2max/D 2min exceeds 5, there will be a decrease in uniformity in the surface of the surface light source, or a possibility of greatly changing the brightness depending on the viewing angle. In the surface light source of the present invention, when the isotropic diffusible film is used as the second optical film 6, the ratio D2max/D2min of the half-web width is 5 or less, and a superior viewing angle can be obtained. 200825468 . Surface light source with characteristics and display characteristics. Here, when D 2 ma X / D 2 mi η is larger than 1 and is in the range of 5 or less, it is preferable to make the diffusion direction of the first optical film 5 in the opposite direction and the diffusion of the second optical film 6 The direction in which the sex is maximum becomes approximately vertical. Here, the term "slightly vertical" means that the angle Θ 7 between the longitudinal direction of the adjacent linear grooves 3 3 or the linear protrusions 34 and the direction in which the diffusibility of the second optical film 6 is maximized is within 90 ± 15°. . 07 is preferably 90±10. Better, less f. It is 90:1=5^. The isotropic diffusing film system preferably has a transmitted light half-web D2min in a direction in which the diffusibility when light is incident from the normal direction is 2 to 50. . It is preferably 3 to 30 °, more preferably 4 to 15. . If D2min is less than 2. At this time, the linear groove 3 3 or the linear protrusion 34 of the light guide 3 is recognized, or the uniformity in the surface light source is lowered, and the possibility of brightness is largely changed depending on the viewing angle. Further, when it exceeds 50°, the utilization efficiency of light is lowered and the brightness of the surface light source is lowered. In this manner, the transmitted light half-web D2min in the direction in which the diffusibility is minimized to W- is 2 to 50. The isotropic diffusing film in the range can be made into a high-intensity surface light source with excellent viewing angle characteristics and uniformity. The haze of the isotropic diffusing film is suitably 70% or more. The haze is preferably more than 7 5 %, and the haze is more preferably 80% or more. Also, haze is a flaw measured after being injected from a smooth surface. When the haze is less than 70%, the in-plane luminance distribution or the viewing angle characteristic of the surface light source is deteriorated because the light cannot be sufficiently diffused. In the surface light source of the present invention, the mist of the second optical film 6 is made -35-200825468. The degree is 70% or more, and a surface light source having high brightness and excellent viewing angle characteristics can be produced. Further, the definition of haze is the same as the definition of the haze of the first optical film 5. The isotropic diffusing film system preferably has a total light reflectance of 50% or more and a haze of 70% or more. More preferably, the total light reflectance is 55 % or more and the haze is 75% or more, and particularly, the total light reflectance is 60% or more and the haze is 80% or more. By making the total light reflectance 50% or more and the haze 70% or more, it is possible to produce a surface light source having high brightness and excellent viewing angle characteristics and uniformity. An example of a specific isotropic diffusible film is shown in Fig. 13. For example, the isotropic diffusible film may be one in which a resin constituting a film and a spherical particle having a different refractive index are contained in the film (Fig. 3 (a)), and a coating film containing spherical particles is formed on the surface of the film (No. 1 (Fig. (b)), forming a substantially dome-shaped approximately dome-shaped object (Fig. 13 (c)), etc., so that the concave-convex shape is formed on at least one surface of the film, or a combination thereof 1) Wait. By forming such a shape, it is possible to find an isotropic diffusivity. The cross-sectional shape of these film or relief shapes may be regular or irregular. In view of the fact that the control of the light diffusibility is easy, it is more preferable to provide the unevenness on the surface of at least one side of the film. The thickness FL2 of the isotropic diffusing film is preferably 30 to 1000 / / m, more preferably 50 to 700 / / m, and particularly preferably 75 to 500 / m / m, based on the viewpoint of the operability or workability of the film. . The thickness FL2 of the film, as shown in the figure 13-36-200825468 - Fig. (a), the surface is smooth, refers to the thickness thereof, as shown in Fig. 13 (b), the shape is only set on one side. The case of the surface refers to the thickness from the apex of the convex portion until the side surface of the shape is not provided. Further, the case where the shape is provided on both sides means the thickness from the apex of the convex portion of one surface to the apex of the convex portion of the other side surface. As shown in Fig. 13 (c), depending on the position, when the height is different, the average 値 is taken as the thickness FL2 of the second optical film 6. Also, the thickness of the film is the same as that of the ruthenium. Γ:: As shown in Fig. 13 (a), the isotropic diffusible film having an isotropic diffusibility inside the film can be processed into a sheet by a resin material in which approximately spherical particles having different refractive indices are dispersed. I got it later. Further, it is preferable to perform uniaxial or biaxial stretching of the sheet from the viewpoint of improving the mechanical strength. In addition, the planar stability and dimensional stability are imparted to the film which has been subjected to uniaxial or biaxial stretching, and further, if necessary, to completely eliminate voids generated between the approximately spherical particles having different refractive indices Li and the resin (void Then, by heat treatment (heat setting) in the tenter, after the heat treatment, it is uniformly cooled, and then cooled to near room temperature to produce an isotropic diffusible film in which spherical particles are dispersed inside the film. . Further, the isotropic diffusible film is a method in which an uneven shape is formed on at least one surface of the film and an isotropic diffusibility is observed as shown in Fig. 3 (b), and a coating agent containing fine particles is applied. Method for surface of a film; a method of setting a concavity and convexity on a surface by a hot stamping method or a photolithography method. Needle -37- 200825468 • The method by the hot stamping method or the photolithography method can be produced by the same method as the method of the first optical film 5. It is also possible to blend various additives such as an antioxidant, a heat stabilizer, a weathering stabilizer, a UV absorber, and an organic one in the second optical film 6 used in the present invention, without departing from the effects of the present invention. Slip agents, pigments, dyes, chelating agents, antistatic agents and nucleating agents. [High-brightness] g The surface light source of the present invention uses the film having the diffusivity in the opposite direction as the I' first optical film 5, and the direction in which the diffusibility is maximized and the linear groove of the light guide 3 are obtained. The direction of the 3 3 or the linear protrusions 34 is arranged approximately in parallel, and high luminance can be expected. Further, by arranging the specific film as the second optical film 6, it is possible to form a surface light source having high brightness, superior viewing angle characteristics, and uniformity which cannot be achieved by a conventional surface light source. Explain the details. First, explain the mechanism for achieving high brightness. Figure 1 4 shows the light transmission characteristics of the cymbal. The light (λ i 1 ) incident on the prism lens from the vicinity of the normal direction is repeatedly reflected at the 稜鏡/air interface, and the result is returned to the opposite direction of the normal without passing through the cymbal. If the reflection of the return light is performed using the reflection sheet, it can be reused. However, if the reflection is repeated, the light will be inactivated and the like, and the light will be lost. Then, the light (λ i 3 ) of the cymbal is incident at a large angle, and the reflection on the surface of the sheet is large. In addition, even if it is incident, it is refracted in the opposite direction to the normal direction at the 稜鏡/air interface to become lost. Therefore, become -38- 200825468 - loss of light. On the other hand, light (λ 丨 2 ) incident at an incident angle of ± 30 ° can be refracted by the incident surface and the prism/air interface, respectively, and is effectively polarized in the normal direction. Therefore, in order to increase the brightness of the enamel sheet, it is important to increase the λ i 2 component. The case where the configuration of the prism sheet is not used 'can not be directed to the normal direction due to the refraction of the surface as in the case of using the prism sheet. Therefore, it is necessary to make the p-direction of the light guide 3 mostly directed toward the normal direction in order to reduce the degree of p. That is, in order to increase the brightness, it is important to control the type of the optical film and the emission characteristics from the light guide 3. Specifically, in the case where a ruthenium film is used as the second optical film, it is increased by an incident angle of ±3 〇. The light that is injected nearby will become important. Further, in the case where the second optical film is not provided, when the isotropic diffusible sheet is used as the second optical film, it is important to increase the light in the normal direction. Based on the above-described idea, a mechanism for increasing the brightness of the surface light source of the present invention will be described using the first to fifth embodiments. The surface light source of the present invention is not limited by such mechanisms. Fig. 15 is a view schematically showing the light that is transmitted through the light guide body and emitted. Fig. 15(a) is a view schematically showing light propagating in the light guide 3. In the example of this figure, the light guide 3 is formed on the opposite side of the light exit surface 3 2 to form a triangular linear groove 3 3 . The light incident from the light incident surface 31 has light that is parallel to the surface of the light guide 3 and that is not irradiated to the light exit surface 32 and the light non-emission surface 35; and the light guide 3 Light exit surface 3 2 or light non-emissive surface -39- 200825468 . The total reflection is repeated on the 3 5 to propagate the light in the light guide 3 . Among the light in the light guide 3, the light striking the linear groove 3 is reflected by the surface of the groove 3 to change its traveling direction. As a result, it is incident on the light exit surface 3 2 at an angle or less, and is emitted outside the light guide body 3 (Fig. 15 λρΐ, λρ2, λ ρ 3). Fig. 15 (b) to (g) show the collision. A diagram of the optical path of the light of the linear groove 3 3 protrusions 34. In the case of the f-line groove 3 in Fig. 15 (b) to (g), the case of the linear protrusion 34 is also the phase [1, and the figure 15 (b) to (d) are located. An example in which the inclined surface of the light source side of the groove of the light guide body is disposed at an angle of 45° with respect to a line perpendicular to the light source 1; (5) to (g) of the first embodiment are located at the light guide body The slope of the light source side of the linear groove is at an angle of 0 1 = 40 perpendicular to the line of the light source. An example of the situation. Fig. 15(b) and (e) are examples of light that collides with the light guide surface in a direction parallel to the light guide body; Fig. (d) and (g) collide with the linear groove from the light non-ejecting surface 35. Fig. 15 (c) and (f) are examples of light which is reflected from the non-emission surface 35 and hits the linear groove 33. Further, θ 1 is 42. Under the condition of 5 to 50°, the principle can be considered to be the same as 0 1 = 45 °; 0 1 is 42. In the case of 5°, it can be considered that the same as θ 1 and 40°. In addition, in the case of the linear protrusions 34, Θ 2 is also the same as 0 1 . θ 1 = 45. In the case, as shown in Fig. 15(b), the light that strikes the linear groove 3 3 or the linear protrusion 34 of the surface of the light guide 3 is λ (the λ is attached to the inclined surface for total reflection, and the light guide is emitted. 3 light exit surface 3 2 propagate linear critical (a)' or line example 3. Linear Θ 1 is placed straight. It is the 15th light and the situation is 20~ rational. Parallel Pi) about 40- 200825468 Slightly normal direction (λ ο 1 ). However, since the shadow of the adjacent linear grooves 3 3 is actually formed, the amount of light following this path is small. Therefore, as shown in Fig. 15 (〇, most of the light is struck from the light exit surface 32 side toward the linear groove 33, or as shown in Fig. 15(d), after being reflected from the light non-ejecting surface 35 side The linear groove 33 is struck. As shown in Fig. 15(c), the light λ p2 striking the linear groove 3 from the light exit surface 32 side is totally reflected so that the inclined surface thereof returns to the light source 1 side. As shown in Fig. 15(d), the light λ p 3 which is reflected from the light non-ejecting surface 35 side and strikes the linear groove 3 3 is totally reflected by the inclined surface to the side opposite to the light source 1 side. The light reflected by the slope is opposite to the normal direction of the light exit surface 32, and is refracted to emit (λ 〇2, λ 〇3). That is, in the case of θ 1 = 45, many rays can be directed toward The direction of inclination away from the direction of the normal direction. On the other hand, in the case of 0 1 = 40, as shown in Fig. 15(e), the linear groove 3 3 which is approximately parallel to the surface of the light guide 3 is struck. The light (λ p 1 ) is totally reflected by the inclined surface thereof, and is incident on the approximate normal direction (λ ο 1 ) of the light exit surface 3 2 of the light guide body 3. However, since it actually becomes a phase The shadow of the adjacent linear groove 3 3 or the linear protrusion 34 is small, so the amount of light following the path is small. Therefore, as shown in Fig. 15 (f), most of the light is emitted from the light exit surface 3 2 the side strikes the linear groove 3 3 or, as shown in Fig. 15 (g), strikes the linear groove 3 3 from the light non-ejecting surface 35. As shown in Fig. 15 (f), the light is emitted from the light. The light λ p2 of the surface 3 2 side striking the linear groove 3 3 is totally reflected so that the inclined surface thereof returns to the light source 1 side, and is opposite to the normal direction of the light exit surface 32, and is refracted to be emitted (λ 〇 2 ) However, this exit angle 0 〇 2 is smaller than 0 1 2 4 5 . -41 - 200825468 ; In addition, as shown in Fig. 15 (2), it is reflected from the side of the light non-ejecting surface 3 5 The light λ p 3 of the linear groove 3 3 is totally reflected by the inclined surface to the side opposite to the side of the light source 1. The light reflected by the inclined surface is emitted after being refracted in the normal direction of the light exit surface 3 2 ( λ 〇 3 ). This exit angle 0 〇 3 is larger than 0 1 = 45°. θ 1 is 40. In the case where the reflected light is incident on the light exit surface 32 of the light guide 3, the angle is Θ 1 = 45. Time is big. So 'after total reflection And returning to the light guide body 3, re-propagating (the light in the light guide body 3 will increase. That is, in the case of 0 1 = 40 0., a lot of light can be directed to the normal direction. According to the above, It is known that if the inclined surface on the side of the linear groove light source provided on the light guide body is controlled, and the angle 0 1 perpendicular to the straight line of the light source 1 is controlled, the light exit surface 3 2 from the light guide body 3 can be controlled. The emitted light. Specifically, θ 1 is 42. 5 to 45. In this case, most of the light can be obliquely emitted; 0 1 is 20 to 42. In the case of 5°, most of the light can be directed toward the normal direction. { Fig. 16 is a view for explaining an example of an emission angle distribution of light emitted from the light exit surface 32 of the light guide 3 in the surface light source of the present invention. Further, the emission angle distribution described in the example of Fig. 6 is a surface light source in which the light guides 3 are sandwiched between the two light sources 1 and the reflection plate 2 as shown in Fig. 2(a). In the middle, an example of the distribution of the emission angle from the central portion of the light exit surface 32 of the light guide 3 is shown. The light guide 3 is an example in which the linear groove 3 3 is formed on the light non-emission surface 35 side in the direction parallel to the light incident surface 3 1 . Also, in Fig. 16 (a), (b) is 0 1 = 45 ° -42 - 200825468, and the exit angle of the case of Fig. 16 (c) and (d) is 0 1 = 40 ° distributed. Fig. 16 (a) and (c) show the distribution of the exit angles in the plane perpendicular to the longitudinal direction of the linear grooves 3 3 (hereinafter, simply referred to as the surface perpendicular to the linear grooves 33). Figs. 6(b) and (d) are in parallel to the in-plane direction of the longitudinal direction of the linear groove 3 3 including the normal direction of the light exit surface 32 (hereinafter, simply referred to as the surface parallel to the linear groove 33). The distribution of the exit angle. Fig. 17 shows a surface light source in which a different direction diffusing film or an isotropic diffusing film is placed on the light source 3 and the light guide 3 is sandwiched between the two light sources 1 and the reflecting plate 2 as shown in Fig. 2(a). An example of the distribution of the exit angle at the central portion of the light guide 3 on the light guide 3. Also, Fig. 17 (a) and (b) are 01 = 45. In the case, Fig. 17 (c) and (d) are 0 1 = 4 0. The exit angle distribution of the situation. Fig. 17 (a) and (c) show the distribution of the exit angle perpendicular to the plane of the linear groove 33. Fig. 17 (b) and (d) are distributions of the exit angles parallel to the plane of the linear grooves 3 3 . The light source of the present invention is used as the angle 0 1 = 4 5 ° of the inclined surface of the light source 1 of the linear groove 3 3 of the light guide body 3, as shown in Fig. 16 (a), perpendicular to the line shape In the plane of the groove 3 3, most of the light can be directed to ± 3 〇. The direction is nearby. On the other hand, in the plane parallel to the linear groove 3 3, it becomes the soil 40. A wide distribution of exit angles with a great point near the direction (Fig. 16(b)). That is, the angle θ 1 of the inclined surface of the light source 1 side of the linear groove 3 is controlled to 45. It is perpendicular to the plane of the linear groove 33, and it is possible to emit light containing a plurality of rays suitable for the direction of the prism. On the other hand, in other planes (for example, parallel to the plane of the linear groove 33), most of the light is directed in a direction other than the direction of the slab -43-200825468. Therefore, if the light can be directed to the appropriate direction of the cymbal, it is possible to achieve high luminance. On the incident surface 32 of the light guide 3 having the emission angle distribution, the emission angle distribution when the opposite-direction diffusion film or the isotropic diffused film is provided is shown in Figs. 7(a) and 7(b). In the case where an isotropic diffusible film is used, the light is uniformly diffused, and the angular distribution of the exit from the light guide 3 is disturbed. In other words, the light emitted from the light guide 3 is large in the vicinity of an emission angle of ±30°, and when passing through the isotropic diffusible film, the amount of light near the emission angle of ±30° is reduced. Therefore, since the amount of emitted light suitable for the direction of the cymbal will be reduced, the efficiency will be lowered. On the other hand, when the diffusing film having the strong diffusivity in the strong and different directions is disposed such that the direction in which the diffusibility is maximized is approximately parallel to the longitudinal direction of the linear groove 33, the diffusion is not perpendicular to the line. In the direction of the groove 3 3 (Fig. 17 (a)), only light having a direction parallel to the longitudinal direction of the linear groove 3 3 is diffused (Fig. 17(b)). As a result, the distribution of the exit angle perpendicular to the plane of the linear groove 3 3 is not disturbed, but j is parallel to the plane of the linear groove 33, and the emitted light can be concentrated on the normal of the light exit surface 32. direction. Thereby, it is possible to increase the light suitable for the angle of the prism sheet. In other words, when the ruthenium sheet is used as the second optical film 6, it is possible to increase the brightness. As described above, when the prism sheet is used as the second optical film 6, it can be seen that the slope of the light source 1 side of the linear groove 33 provided in the light guide 3 is perpendicular to the light source 1. The angle between the straight line; or the inclined surface on the opposite side of the light source 1 of the linear protrusion 34 disposed on the light guide body 3 and the vertical -44-200825468, the angle straight to the line of the light source 1 may be 42. 5 to 50. . Further, in the surface light source of the present invention, the angle 0 1 = 40 of the slope of the light source 1 side of the linear groove 33 of the light guide 3 is set. In the case where it is perpendicular to the plane of the linear groove 33 as shown in Fig. 16(c), most of the light can be directed toward the crucible. Near the direction. On the other hand, in the case of being parallel to the inside of the linear groove 33, most of the light is directed in the vicinity of the ±40° direction (Fig. 16(d)). When the opposite-direction diffusion film is provided on the light guide body, a plurality of light having a direction of 0° can be emitted in a direction perpendicular to the direction of the linear groove 3 (Fig. 17(c)). Further, in the case of the other surface (for example, parallel to the plane of the linear groove 33), when the diffusion film of the different direction is provided, the light which is directed to the direction other than 0° can be directed toward the normal of the light exit surface 32. Direction (Fig. 17(d)). On the other hand, when an isotropic diffusing film is used, the diffusing film is formed in a direction perpendicular to the linear groove 3 or in other faces (for example, parallel to the surface of the linear groove 33). In the meantime, light emitted in the direction other than 0° can be directed to the normal direction of the light exit surface 3 2 (Fig. 17 (c), (d)). That is, it is found that by using the different-direction diffusion film as the first optical film 5, the angle of the slope of the light source 1 side of the linear groove 3 3 is controlled to 40 °, and the light emission in the normal direction is increased. In this manner, if the slope of the light source 1 side of the linear groove 33 provided by the light guide body 3 is at an angle perpendicular to a line perpendicular to the light source 1, or the linear protrusion 34 provided by the light guide body 3 The angle between the slope of the opposite side of the light source 1 and the line perpendicular to the light source 1 is 20 to 4 2 · 5. At the time, the emission of light in the normal direction will increase. Therefore, if this condition is met, it is known that even if -45-200825468 is not used. In the case of the optical film 6, it is also possible to obtain a high-intensity surface light. Further, as described above, when the light-diffusing sheet is used as the second light, if the amount of light in the normal direction is large, the surface brightness can be expected. That is, in this case, the slope of the light source 1 side of the light guide body 3 disposed on the side of the light source 1 and the line perpendicular to the light source 1 are opposite to the light source 1 of the linear protrusion 34 provided by the light guide body 3. The angle perpendicular to the straight line of the light source 1 may be 20 to p [surface light source] The surface light source of the present invention having such a structure has an in-plane luminance of 65% or more. It is more preferably 70% or more, more preferably 75%, and more preferably 80% or more. Here, the uniformity of brightness is measured by a color luminance meter at a viewing angle of 1° in a large screen size of 5 吋 or more, and is displayed in the surface light source 25 of Fig. 18(a); In the case of measuring the brightness of 9 points in the surface light source of Fig. 8(b), the maximum brightness Bmax and the minimum brightness Bmin are also used for the uniformity measurement according to the following equation. For the luminance meter, for example, it is suitable to use BM-7/FAST (Topcon (share) level or higher. U=Bmin/Bmaxx 1 00 in the surface light source of the present invention, by setting the uniformity U to ί" In addition, the surface light source of the present invention is a film 6 in the up and down direction of the screen, which makes the angle of the linear groove of the light source or the opposite side inclined. 5°. Uniformity U above, especially U, is made to measure the brightness angle of the point. 21ϋ From the respective calculations. The learner. ) or equivalent 65% to the wild angle or left -46- 200825468: Any of the right-angled St angles is 20. As described above, the viewing angle in the left-right direction of the screen is preferably 20 or more. More preferably 25. Above, it is best to be 3 〇. the above. Here, the gravitational angle of the stomach refers to the use of a color oximeter, every two. Measure the range of ±80° in the vertical direction of the screen or ±8〇 in the left and right direction of the screen. In the range of the exit angle of the range, when the horizontal axis is the emission angle and the vertical axis is the brightness, the central portion of the surface light source is plotted, and the luminance B() with respect to the normal direction is half brightness (B. / 2). The angle is wide (half width W). By setting the viewing angle of the surface light source of the present invention to a range of 20 or more, the use is not limited, and it can be used as a surface light source which can be used for a wide range of applications. Further, a color gamma meter for measuring the viewing angle can be used by a conventional person. For example, it is suitable to use BM-7/FAST (Top con (share) system) or the same level or higher. The surface light source of the present invention is not limited to this configuration, and other films are inserted into the second optical film 6, between the light guide 3/the first optical film 5, or in the range which does not lose the effect of the present invention. It is also possible to use between the optical film 5 / the second optical film 6 and the like. It is also possible to combine other films. Examples of the film that can be used include other diffusion films, ruthenium films, field-of-view control films, reflective polarizers, brightness enhancement films, polarized separation films, and color compensation films. For example, in the use example, the diffusion film is further disposed on the second optical film 6, and the display quality is improved, and a further brightness enhancement effect can be obtained. Further, when the reflective polarizing plate is disposed such that the polarization axis thereof coincides with the polarization axis of the liquid crystal display device, the light use efficiency can be improved, and the degree of clamshell can be further improved. High brightness and wide viewing angle field of view based on superior light utilization efficiency - 47 - 200825468 Opinion 'The surface light source of the present invention is superior to conventional surface light sources, and can be applied to mobile phones, electronic notebooks, notebook PCs, and surveillance The use of a liquid crystal display element from the back side, such as a TV, various display media, and the like. The liquid crystal display device of the present invention is characterized by loading the surface light source. When the surface light source of the present invention is used, a clear liquid crystal display device having high brightness and excellent viewing angle characteristics and uniformity can be obtained. [Evaluation Method of Characteristics] The evaluation method of the characteristics of the present invention utilizes the method disclosed below. Other devices may be used if the assay device is capable of obtaining the same grade or better results as the evaluation methods below. A. All light reflectance and haze The total light reflectance and haze of the film were measured using a fully automatic direct reading haze computer HGM-2DP manufactured by Suga Test Machine Co., Ltd., Japan. The measurement was carried out by changing the position of the film in the film surface, and the average enthalpy was used as the total light reflectance and haze. Also, the light source uses a standard light source (refer to JIS Z-8720 (2000)). Further, when both the light reflectance and the haze are formed in a concave-convex shape on one side of the optical film, the light is incident from the smoother surface and then measured. Further, if the uneven shape is formed on both surfaces of the optical film, or the both surfaces of the optical film are smooth, the larger one is measured from the two sides. B. Half-width Dmax, Dmin, and ratio Dmax/Dmin The beam is incident from the direction perpendicular to the film surface by using an automatic variable angle photometer GP 200 (manufactured by Murakami Color Technology, Inc. - 48-200825468). The exit angle distribution was obtained after the relative reflectance of 1°. From the result of the obtained emission angle distribution, the half-width D m a X in the direction in which the diffusibility is maximized and the half-width Dmiii in the direction in which the diffusibility is minimized are obtained. After five positions were changed in the film surface, the measurement was performed in the same manner, and the average enthalpy of the half-widths Dmax and Dmin was determined, and the ratio of the half-webs Dmax/Dmin was obtained from the average enthalpy. Further, any one of the half widths Dmax and Dnnn is measured after being incident from the smooth surface. C. The shape of the light guide is evaluated using a three-dimensional shape measuring device NH-3SP (manufactured by Japan Sanying Optical Co., Ltd.) at a magnification of 100 times (short focus) and a scanning interval of 0. 1 / m, the depth H1 of the linear groove 33 of the light guide body, the height H2 of the linear protrusion 34, the inclination angle θ 1 or 0 of the light source 1 side, and the surface of the light exit surface 32 of the light guide 3 are measured. Roughness Ra. D. Thin film cross-section structure After the cross section of the film was cut and platinum-palladium was vapor-deposited, the electric field emission scanning electron microscope "JTSM-6700F" manufactured by JEOL Ltd. was used to take a photograph. In the thin 0-face, the position was changed after changing 5 positions. From the respective cross-sectional photographs, the concave-convex shape (height 宽度, width S, aspect ratio H/S of the convex portion) of the film surface was determined as the dispersion state (dispersion diameter R) inside the film, and the average enthalpy was used to form the uneven shape of the film surface. (Height Η, width S, aspect ratio H/S of the convex portion) Dispersion state inside the film (dispersion -49 - 200825468 _ diameter R). Ε·Brightness, uniformity, and viewing angle arrangement light source 1, “Lumirror” (registered trademark) E6 SV (manufactured by Tor ay (share)) as reflector 2, light guide 3, "L umirror" (registered trademark) E6SL (The Tor ay (manufactured by the company)) A surface light source is produced as the reflection sheet 4 on the lower side of the light guide 3, on the first optical film 5 on the upper side of the light guide 3, and on the second optical film 6. After 10 minutes, using a color brightness meter BM-7/FAST (manufactured by Topcon Co., Ltd.), in the case of a large screen size of 5 吋 or more, r ' is measured at a measured viewing angle of 1 ° and is shown in Fig. 18 (a). When the brightness of 25 points in the surface light source is used; the case of the screen size below 5 ' 'to determine the viewing angle 〇. 2. The brightness at 9 o'clock in the surface light source shown in Fig. 18(b) was measured. The center luminance obtained was determined by the following criteria: 1) When the ruthenium film is used as the second optical film, the center luminance is 6800 cd/m 2 or more when the ruthenium is used as the second optical film: A ^ i center luminance is 6700 cd/m 2 or more. In the case of less than 6800 cd/m2:

BB

中心亮度爲6600cd/m2以上、未滿6700cd/m2之情形： CThe case where the center brightness is 6600 cd/m2 or more and less than 6700 cd/m2: C

中心亮度爲6500cd/m2以上、未滿6600cd/m2之情形·· D 中心亮度未滿6500cd/m2之情形：E 7吋之情形 -50- 200825468The case where the center brightness is 6500 cd/m2 or more and less than 6600 cd/m2. · The case where the D center brightness is less than 6500 cd/m2: The case of E 7吋 -50- 200825468

. 中心亮度爲7 3 00cd/m2以上之情形：A. The case where the center brightness is 7 3 00 cd/m2 or more: A

中心亮度爲7200cd/m2以上、未滿7 3 00cd/m2之情形： BThe case where the center brightness is 7200 cd/m2 or more and less than 7 3 00 cd/m2: B

中七、壳度爲7100cd/m以上、未滿7200cd/m2之情形： CIn the case of Zhongqi, the shell degree is above 7100 cd/m and less than 7200 cd/m2: C

中心亮度爲7000cd/m2以上、未滿7100cd/m2之情形： DThe case where the center brightness is 7000 cd/m2 or more and less than 7100 cd/m2: D

中心亮度未滿7000cd/m2之情形：E f i . 1 3 . 3吋之情形The case where the center brightness is less than 7000 cd/m2: E f i . 1 3 .

中心亮度爲43 00cd/m2以上之情形：A 中心亮度爲4200cd/m2以上、未滿4 3 00cd/m2之情形： BThe case where the center luminance is 43 00 cd/m2 or more: A case where the center luminance is 4200 cd/m2 or more and less than 4 3 00 cd/m2: B

中心亮度爲4 1 0 0 c d / m2以上、未滿4 2 0 0 c d / m2之情形： C 中心亮度爲4000cd/m2以上、未滿4100cd/m2之情形：〇中心亮度未滿4000cd/m2之情形：E 1 . 8吋之情形When the center brightness is 4 1 0 0 cd / m2 or more and less than 4 2 0 0 cd / m2: The C center brightness is 4000 cd/m2 or more and less than 4100 cd/m2: 〇The center brightness is less than 4000 cd/m2. Situation: E 1 . 8吋 situation

中心亮度爲63 00cd/m2以上之情形：A 中心亮度爲6 2 0 0 c d / m2以上、未滿6 3 0 0 c d / m2之情形： BWhen the center brightness is 63 00 cd/m2 or more: A center brightness is 6 2 0 0 c d / m2 or more, less than 6 3 0 0 c d / m2: B

中心売度爲6 1 0 0 c d / m2以上、未滿6 2 0 0 c d / m2之情形： C -51 - 200825468 ，中心亮度爲6000cd/m2以上、The case where the center width is 6 1 0 0 c d / m2 or more and less than 6 2 0 0 c d / m2: C -51 - 200825468 , the center brightness is 6000 cd/m2 or more.

D 中心亮度未滿6000cd/m2之情 2 )將等方向擴散性片作爲第 1 7吋之情形中心亮度爲5 5 00cd/m2以上之The brightness of D center is less than 6000 cd/m2. 2) The case where the isotropic diffuser is used as the first 7 吋 The center brightness is 5 5 00 cd/m2 or more.

中心亮度爲5400cd/m2以上、 B (The center brightness is 5400 cd/m2 or more, B (

中心亮度爲5 3 00cd/m2以上、 CThe center brightness is 5 3 00 cd/m2 or more, C

中心亮度爲5 200cd/m2以上、 D 中心亮度未滿5200cd/m2之情 7吋之情形中心亮度爲5 8 00cd/m2以上之The center brightness is 5 200 cd/m2 or more, and the D center brightness is less than 5200 cd/m2. 7 中心 The center brightness is 5 8 00 cd/m2 or more.

中心亮度爲5700cd/m2以上、 BThe center brightness is 5700 cd/m2 or more, B

中心亮度爲5600cd/m2以上、 CThe center brightness is 5600 cd/m2 or more, C

中心亮度爲5 5 00cd/m2以上、 D 中心亮度未滿5 5 00cd/m2之情 1 3 . 3吋之情形The center brightness is 5 5 00 cd/m2 or more, and the D center brightness is less than 5 5 00 cd/m2. 1 3 .

未滿6100cd/m2之情形：形：E 2光學薄膜使用之時情形：A 未滿5 5 0 0 c d / m2之情形：未滿5400cd/m2之情形·· 未滿5 3 00cd/m2之情形：形：E 情形：A 未滿5 8 00cd/m2之情形：未滿5700cd/m2之情形：未滿5 600cd/m2之情形：形：E 52- 200825468In the case of less than 6100 cd/m2: Shape: When E 2 optical film is used: A is less than 5 5 0 0 cd / m2: less than 5400 cd/m2 · less than 5 3 00 cd/m2 : Shape: E Case: A less than 5 8 00 cd/m2: Less than 5700 cd/m2: Less than 5 600 cd/m2: Shape: E 52- 200825468

• 中心亮度爲3 3 00cd/m2以上之情形：A 中心亮度爲3200cd/m2以上、未滿3 3 00cd/m2之情形：• When the center brightness is 3 3 00 cd/m2 or more: A center brightness is 3200 cd/m2 or more and less than 3 3 00 cd/m2:

BB

中心亮度爲3100cd/m2以上、未滿3200cd/m2之情形： CThe case where the center brightness is 3100 cd/m2 or more and less than 3200 cd/m2: C

中心亮度爲3000cd/m2以上、未滿3100cd/m2之情形： DThe case where the center brightness is 3000 cd/m2 or more and less than 3100 cd/m2: D

/ 中心亮度未滿3000cd/m2之情形·· E Γ 1 . 8吋之情形/ When the center brightness is less than 3000 cd/m2·· E Γ 1. 8吋

中心亮度爲5 3 00cd/m2以上之情形：AThe case where the center brightness is 5 3 00 cd/m2 or more: A

中心亮度爲5 200cd/m2以上、未滿5 300cd/m2之情形： BThe case where the center brightness is 5 200 cd/m 2 or more and less than 5 300 cd/m 2 : B

中心亮度爲5100cd/m2以上、未滿5 200cd/m2之情形： CThe case where the center brightness is 5100 cd/m2 or more and less than 5 200 cd/m2: C

中心亮度爲5000cd/m2以上、未滿5100cd/m2之情形： DThe case where the center brightness is 5000 cd/m2 or more and less than 5100 cd/m2: D

中心亮度未滿5 000cd/m2之情形：E 不ot A、B、C、D均爲良好的，E並非良好的。優越之順序係依照A、B、C、D ( A最爲優越）。另外，從各自所得的結果，求出最大亮度Bmax及最小亮度Bmin，根據下式而算出均勻度U: U= Bmin/Bmaxx 1 00 利用以下之基準評估所得的値： -53- 200825468The case where the center brightness is less than 5 000 cd/m 2 : E is not ot A, B, C, D are all good, and E is not good. The order of superiority is based on A, B, C, and D (the most superior). Further, from the results obtained by the respective results, the maximum brightness Bmax and the minimum brightness Bmin were obtained, and the uniformity U was calculated according to the following formula: U = Bmin / Bmaxx 1 00 The 値 obtained by the following criteria was evaluated: -53- 200825468

. 均勻度U爲8 0 %以上之情形：A 均勻度U爲7 Ο %以上、未滿8 Ο %之情形：B 均勻度U爲未滿7 0 %之情形：C A、B爲良好的，C並非良好的。A最爲優越。接著，針對面光源之中心部分，每隔2 °分別測定畫面上下方向±80。之範圍、或是畫面左右方向±80°之範圍的射出角分布，橫軸設爲射出角、縱軸設爲亮度而進行作圖時，相對於法線方向之亮度B。，將一半亮度（B〇/2 )時之角度 ί 寬（半値幅W )設爲視野角。利用以下之基準評估所得的値：The case where the uniformity U is 80% or more: A uniformity U is 7 Ο % or more, less than 8 Ο %: B uniformity U is less than 70%: CA, B is good, C is not good. A is the most advantageous. Next, for the center portion of the surface light source, the vertical direction of the screen is measured by ±80 every 2 °. The range of the emission angle in the range of ±80° in the horizontal direction of the screen, the horizontal axis is the emission angle, and the vertical axis is the brightness, and the luminance B is plotted against the normal direction. , the angle ί width (half width W) at half brightness (B〇/2) is set as the viewing angle. Use the following benchmarks to evaluate the resulting 値:

視野角爲3 0 °以上之情形：A 視野角爲2 5 °以上、未滿3 0 °之情形：B 視野角爲未滿2 5 °之情形：C A、B爲良好的，C並非良好的。A最爲優越。 [實施例] 以下，針對本發明，列舉實施例而加以說明，惟本發明未必受此等實施例所限定。於實施例、比較例使用之導光體之形狀、製法係如下所示： (導光體A-1 ) 畫面尺寸：17吋（導光體尺寸：縱280mmx橫349.8mm X厚6 m m、線狀溝形成面積：縱2 7 5 m m X橫3 4 9 m m，從距離光射入面內側2 · 5 mm起，於光非射出面側形成線狀溝，光 -54- 200825468 _ 射出面側係平滑面（表面粗糙度Ra= 8nm))。線狀溝：剖面形狀係等腰三角形（頂角90。、0 1二 4 5 ° )，線狀溝係平行於光射入面且間距2 0 0 // m間隔所形成。各線狀溝係於溝之長邊方向，深度呈現不規則變化。最靠近光射入面側之線狀溝的平均深度爲1 1 // m。線狀溝的平均深度係離光射入面越遠、線狀溝越深。中央部之線狀溝的平均深度爲3 3 // m。製法：將已使該形狀予以反轉的模具與6mm厚之聚碳 ί 酸酯樹脂” Upiron” （註冊商標）HL-4000 (日本三菱工程塑膠（股份）製）之樹脂板加熱至160°C，接著以5Q0kN 壓縮30秒鐘。其次，冷卻至80°C後，釋出壓力後而進行脫模。切斷所得的成形品之外圍後而整理形狀，得到導光體 3 ° (導光體A-2) 畫面尺寸：7吋（縱9 2 m m X橫1 5 8 m m X厚3 0 0 m m、線狀 ^ 溝形成面積：縱 88mmx橫 3 47mm，從距離光射入面內側 2.0mm起，於光非射出面側形成線狀溝，光射出面側係平滑面（表面粗糙度Ra=9nm))。線狀溝：剖面形狀係等腰三角形（頂角90°、0 1二 45。），線狀溝係平行於光射入面且間距200 // m間隔所形成。各線狀溝係於溝之長邊方向，深度呈現不規則變化。最靠近光射入面側之線狀溝的平均深度爲1 〇 # m。線狀溝的平均深度係離光射入面越遠、線狀溝越深。中央部之線 -55- 200825468 - 狀溝的平均深度爲3 6 μ m。製法：使用已使該形狀予以反轉的模具酯樹脂” Upiron” HL-4000(日本三菱工程塑f 以進行射出成形，得到縱92mmx橫I58mmx厚的導光體3。 (導光體A-3 ) 畫面尺寸：13 · 3吋（導光體形狀：縱 2 89.2 8mmx厚〇.3mm、線狀溝形成面積：縱 2 8 7 m m，從距離光射入面內側2 · 5 m m起，於3 形成線狀溝。光射出面側係平滑面（表面： 6 n m ) ) 〇線狀溝：剖面形狀係等腰三角形（頂角 45° )，線狀溝係平行於光射入面且間距200 // 成。各線狀溝係於溝之長邊方向，深度呈現不最靠近光射入面側之線狀溝的平均深度爲1 0 , I 的平均深度係離光射入面越遠、線狀溝越深。面最遠之線狀溝的平均深度爲32 // m。製法：使用已使該形狀予以反轉的模具，之聚碳酸酯樹脂” Upiron” HL-4000 (日本三 (股份）製）之樹脂板加熱至160 °C，接著以 30秒鐘。其次，冷卻至80 °C後，釋出壓力後ί 切斷所得的成形品之外圍後而整理形狀’得到 (導光體Α-4 ) 利用聚碳酸 (股份）製） 3 m m之板狀 186.5mmx 橫 1 8 4.0 m m X 橫非射出面側 .糙度 Ra = 90〇、θ 1 = m間隔所形規則變化。〃 m。線狀溝距離光射入將0.3 m m厚菱工程塑膠 300kN壓縮 ί進行脫模。導光體3。 -56- 200825468 . 畫面尺寸· 1.8时（導光體尺寸：縱40mmx橫30.5mmx 厚0.7mm、線狀溝形成面積：縱37mmx橫30mm，從光射入面起分開2.8mm間隔，於光非射出面側形成線狀溝。光射出面側係平滑面（表面粗糙度R a = 1 0 n m ))。線狀溝：剖面形狀係等腰三角形（頂角 90。、0 1二 45 ° )，線狀溝係平行於光射入面且間距200 // m間隔所形成。各線狀溝係於溝之長邊方向，深度呈現不規則變化。最靠近光射入面側之線狀溝的平均深度爲1 . 8 // m。線狀溝 f - ^ 的平均深度係離光射入面越遠、線狀溝越深。距離光射入面最遠之線狀溝的平均深度爲3 1 /z m。製法：使用已使該形狀予以反轉的模具，利用聚碳酸酯樹脂” Upiron” HL-4000(日本三菱工程塑膠（股份）製）以進行射出成形後而得到導光體3。 (導光體A-5 ) 畫面尺寸：17吋（導光體尺寸：縱280mmx橫349.8mm _ X厚6 m m、線狀溝形成面積：縱2 7 5 m m X橫3 4 9 m m，從距離光射入面內側2.5 mm起，於光非射出面側形成線狀溝，光射出面側係平滑面（表面粗糙度Ra= 8nm))。線狀溝：剖面形狀係等腰三角形（頂角1 00。、Θ 1 = 40° )，線狀溝係平行於光射入面且間距200 // m間隔所形成。各線狀溝係於溝之長邊方向，深度呈現不規則變化。最靠近光射入面側之線狀溝的平均深度爲1 2 // m。線狀溝的平均深度係離光射入面越遠、線狀溝越深。中央部之線 -57- 200825468 , 狀溝的平均深度爲3 4 // m。製法：將已使該形狀予以反轉的模具與6mm厚之聚碳酸酯樹脂” Upiron” （註冊商標）HL-4000 (日本三菱工程塑膠（股份）製）之樹脂板加熱至160t，接著以500kN 壓縮3 0秒鐘。其次，冷卻至8 0 °C後，釋出壓力後而進行脫模。切斷所得的成形品之外圍後而整理形狀，得到導光體 3 ° (導光體A-6) (· 畫面尺寸：7吋（縱92mmx橫158mmx厚3 00mm、線狀溝形成面積：縱88mmx橫347mm，從距離光射入面內側 2.0mm起，於光非射出面側形成線狀溝，光射出面側係平滑面（表面粗糙度Ra= 9nm))。線狀溝：剖面形狀係等腰二角形（頂角1 〇〇。、0 1 = 40 ^ )’線狀溝係平行於光射入面且間距200 // m間隔所形成。各線狀溝係於溝之長邊方向，深度呈現不規則變化。 (, 最靠近光射入面側之線狀溝的平均深度爲1 1 // m。線狀溝的平均深度係離光射入面越遠、線狀溝越深。中央部之線狀溝的平均深度爲3 6 /z m。製法：使用已使該形狀予以反轉的模具，利用聚碳酸酯樹脂” Upiron” HL-4000(日本三菱工程塑膠（股份）製）以進彳了射出成形，得到縱9 2 m m X橫1 5 8 m m X厚3 m m之板狀的導光體3。 (導光體A-7 ) -58- 200825468 - 畫面尺寸：13.3吋（導光體尺寸：縱186.5mmx橫 2 8 9 · 2 8 m m X厚 0 · 3 m m、線狀溝形成面積··縱1 8 4.0 m m X橫 2 8 7 m m，從距離光射入面內側2 · 5 m m起，於光非射出面側形成線狀溝。光射出面側係平滑面（表面粗糙度Ra二 7nm ))。線狀溝：剖面形狀係等腰三角形（頂角1 〇〇。、Θ 1二 40 0 )，線狀溝係平行於光射入面且間距200 // m間隔所形成。各線狀溝係於溝之長邊方向，深度呈現不規則變化。 f '· V 最靠近光射入面側之線狀溝的平均深度爲1〇//!!1。線狀溝的平均深度係離光射入面越遠、線狀溝越深。距離光射入面最遠之線狀溝的平均深度爲3 2 // m。製法：使用已使該形狀予以反轉的模具，將〇.3mm厚之聚碳酸酯樹脂” Upiron” （註冊商標）HL-4000 (日本三菱工程塑膠（股份）製）之樹脂板加熱至160 °C，接著以 3 00kN壓縮30秒鐘。其次，冷卻至8(TC後，釋出壓力後而進行脫模。切斷所得的成形品之外圍後而整理形狀，得到導光體3。 (導光體A-8 ) 畫面尺寸：1·8吋（導光體尺寸：縱40mmx橫30.5mmx 厚0.7mm、線狀溝形成面積：縱37mmx橫30mm，從光射入面起分開2.8mm間隔，於光非射出面側形成線狀溝。光射出面側係平滑面（表面粗糙度Ra= 8nm))。線狀溝：剖面形狀係等腰三角形（頂角1 00。、0 1 = -59- 200825468 40° ) ’線狀溝係平行於光射入面且間距200 // m間隔所形成。各線狀溝係於溝之長邊方向，深度呈現不規則變化。最靠近光射入面側之線狀溝的平均深度爲2 // m。線狀溝的平均深度係離光射入面越遠、線狀溝越深。中央部之線狀溝的平均深度爲3 1 // m。製法：使用已使該形狀予以反轉的模具，利用聚碳酸酯樹脂” Upiron” HL-4000(日本三菱工程塑膠（股份）製）以進行射出成形後而得到導光體3。針對該導光體，於表1整理尺寸、形態（線狀溝或線狀突起之分別）、線狀溝之形成面、線狀溝3 3之光源丨側之斜面與垂直於光源之直線的夾角0 1與相對於光源1之線狀突起3 4之斜面與垂直於光源之直線的夾角0 2之別、線狀溝的深度Η 1或線狀突起的高度H2、線狀溝或線狀突起的間距Ρ。 -60- 200825468 【表1】尺寸 (吋）形態形成面 01 或 02 (〇) H1 或 H2 (Um) P (//m) A-1 17 線狀溝非射出面 45 11 〜33 200 A-2 7 線狀溝非射出面 45 10 〜36 200 A-3 13.3 線狀溝非射出面 45 10 〜32 200 A-4 1.8 線狀溝非射出面 45 1.8 〜31 200 A-5 17 線狀溝非射出面 40 12 〜34 200 A-6 7 線狀溝非射出面 40 11 〜36 200 A-7 13.3 線狀溝非射出面 40 10 〜32 200 A-8 1.8 線狀溝非射出面 40 2〜31 200 另外，於實施例、比較例使用之光學薄膜係如下所述： (光學薄膜B-1 ) 形狀：使利用光干涉法所得的約略正弦狀之無規條紋圖案形成於薄膜表面（平均間距1 5.6 // m、平均縱橫比（二平均高度/平均間距）0.63 )。製法：進行” Adekaoptomer” （註冊商標）KRM-2199 (日本旭電化工業（股份）製）10重量份、Aron Oxetane 〇X 丁-221 (曰本東亞合成（股份）製）1 重量份、” Adekaoptomer” SP170 (日本旭電化工業（股份）製）〇· 25重量份之混合與攪拌後而得到塗布液。接著，於將該塗布液賦與模具之表面形狀的表面上，以使塗膜的厚度成爲50//m之方式來塗布。塗布後，於塗膜上面重疊聚酯薄 -61 - 200825468 • 膜 ” Lumirror” #l〇〇U34(Toray (股份）製）從薄膜側施加壓力後而予以貼合。接著，維㈣從薄膜面側照射合計1 0 0 0 m J / C m2之紫外線後，脫模後而得到將表面凹凸形狀賦與基材薄膜之學薄膜。 (光學薄膜B-2) 形狀：圓柱透鏡形（以間距4 0 // m，使转剖面爲高5 0 μ m、寬5 0 // m之半橢圓形配列於 f 照第19圖））。製法：除了將已反轉該形狀之模具作爲外，利用相同於B -1之方法加以製造。 (光學薄膜B - 3 ) 形狀：將長軸200 // m、短軸20 /z m、高g 紡錘狀突起配列於薄膜表面（參照第20圖）製法：除了將已反轉該形狀之模具作爲外，利用相同於B -1之方法加以製造。 (光學薄膜B-4) 形狀：使棒狀粒子單向配列於薄膜內部。平均短徑3//m、平均長徑500//m。製法：將94體積％之作爲構成光擴散® 分，其相對於聚對苯二甲酸乙二醇酯（PET ) ^ 10m〇1%的間苯二甲酸成分、相對於二醇單位環己烷二甲醇成分予以共聚合之聚酯樹脂（β ，利用滾筒此狀態下，進行模具之一側面的光 1長邊方向之薄膜表面（參模具使用以 t 20 μ m之半 )° 模具使用以 >棒狀粒子之 I主要樹脂成戸之酸單位爲爲 1 0 m ο 1 %的容點TB : 225 -62- 200825468 • °c )，及6體積％之作爲光擴散元件的聚甲基戊烯（日本三井化學（股份）製），混合而成之九粒供應至主擠出機。另外，使用有別於主擠出機之副擠出機，將PET(熔點TA : 265 t )供應至此副擠出機。接著，使供應至主擠出機之成分層兩側表層與供應至副擠出機之成分層的厚度比率，成爲副擠出機之成分層：主擠出機之成分層：副擠出機之成分層=1 : 8 : 1之方式來進行熔融3層積層的共擠出。利用靜電施加法，將所擠出的樹脂，在以擠出速度之一倍速度 f ' 旋轉的澆鑄轉筒上進行冷卻後而製得3層積層片。於溫度 87 °C，沿著此積層片之長邊方向拉伸3.2倍，接著，利用拉幅器，通過9 5 t之預熱區，於1 1 0 °C沿著寬度方向拉伸 3.4倍。進一步藉由將熱處理溫度Th設爲2 3 5 °C，進行3 0 秒鐘之熱處理後而得到於內部棒狀粒子配列於薄膜行進方向所含有的厚度180 /z m的薄膜。 (光學薄膜B-5 ) (1 使用 Toray Sehan 製之擴散膜” TEXCELL” TDS127。 (光學薄膜B-6) 使用Millea Nanotec製之擴散膜UTEII。 (光學薄膜B - 7 ) 形狀：於單面上，使長軸3 0 // m、短軸2 0 // m、高度 2 0 // m之半紡錘狀突起予以配列（參照第2 1圖）。製法：除了將已反轉該形狀之模具作爲模具使用以外，利用相同於B -1之方法加以製造。 -63- 200825468 . (光學薄膜B-8 ) 使用 Toray Sehan 製之擴散膜” TEXCELL” TDA128。 (光學薄膜B-9) 使用Kimoto (股份）製之擴散膜DX2。 (光學薄膜C-1 ) 3M製之稜鏡片BEFIII90/50T。 (光學薄膜C-2) 使用Mi lie a Nano tec製之稜鏡片THIN-T2。 c、 (光學薄膜C-3 ) 形狀：稜鏡條紋（頂角0 3 = 100°、間距50 μ m、高度 2 \ β m)。製法：將已使該形狀予以反轉的模具（縱280mmx橫 350mm)與0.2mm厚之聚碳酸酯樹脂” Upiron” HL-4000(日本三菱工程塑膠（股份）製）之樹脂板加熱至1 60°C，接著以500kN壓縮30秒鐘。其次，冷卻至80°C後，釋出壓力 I 後而進行脫模，得到光學薄膜。針對該光學薄膜，將透過光半値幅之最大値Dmax、最小値D m i η、D m a X / D m i η、全部光線反射率、霧度、稜鏡片之頂角0 3、稜鏡的間距、與稜鏡之高度顯示於表2、3。 -64- 200825468 【表2】When the viewing angle is more than 30 °: A: The viewing angle is 2 5 ° or more, less than 30 °: B: The viewing angle is less than 2 5 °: CA, B is good, C is not good. . A is the most advantageous. [Examples] Hereinafter, the present invention will be described by way of examples, but the present invention is not necessarily limited by the examples. The shape and manufacturing method of the light guide used in the examples and comparative examples are as follows: (light guide A-1) Screen size: 17 吋 (light guide size: vertical 280 mm x horizontal 349.8 mm X thickness 6 mm, line Area of formation of the groove: vertical 2 7 5 mm X transverse 3 4 9 mm, from the inside of the light incident surface 2 · 5 mm, forming a linear groove on the side of the light non-ejecting surface, light -54- 200825468 _ exit side It is a smooth surface (surface roughness Ra = 8 nm)). Linear groove: The profile shape is an isosceles triangle (apex angle 90., 0 1 2 4 5 °), and the linear groove is formed parallel to the light incident surface and spaced at intervals of 2 0 0 // m. Each linear groove is in the longitudinal direction of the groove, and the depth changes irregularly. The linear groove closest to the side of the light incident surface has an average depth of 1 1 // m. The average depth of the linear grooves is farther from the light incident surface and the deeper the linear grooves. The average depth of the central groove is 3 3 // m. Method: The mold of the 6mm thick polycarbonate resin "Upiron" (registered trademark) HL-4000 (manufactured by Mitsubishi Engineering Plastics Co., Ltd.) is heated to 160 ° C. Then, it is compressed at 5Q0kN for 30 seconds. Next, after cooling to 80 ° C, the pressure was released and demolding was carried out. After cutting the outer periphery of the obtained molded article, the shape was arranged to obtain a light guide 3° (light guide A-2). Screen size: 7吋 (vertical 9 2 mm X horizontal 1 5 8 mm X thickness 3 0 0 mm, Linear groove forming area: vertical 88 mm x width 3 47 mm, from the inner side of the light incident surface 2.0 mm, a linear groove is formed on the light non-ejecting surface side, and the light emitting surface side is smooth (surface roughness Ra = 9 nm) ). Linear groove: The profile shape is an isosceles triangle (90° apex angle, 0 1 2 45). The linear groove is formed parallel to the light incident surface and spaced at a spacing of 200 // m. Each linear groove is in the longitudinal direction of the groove, and the depth changes irregularly. The linear groove closest to the side of the light incident surface has an average depth of 1 〇 # m. The average depth of the linear grooves is farther from the light incident surface and the deeper the linear grooves. The line of the central part -55- 200825468 - The average depth of the groove is 3 6 μ m. Method: Using a mold ester resin "Upiron" HL-4000 (Japan Mitsubishi Engineering Plastics f) to perform injection molding, a light guide 3 having a length of 92 mmx and a width of I58 mmx was used. (Light guide A-3 ) Screen size: 13 · 3吋 (light guide shape: vertical 2 89.2 8mmx thick 〇.3mm, linear groove forming area: vertical 2 8 7 mm, from 2 · 5 mm from the inside of the light incident surface, at 3 A linear groove is formed. The smooth surface of the light exit surface is smooth (surface: 6 nm). The linear groove: the cross-sectional shape is an isosceles triangle (appropriate angle of 45°), and the linear groove is parallel to the light incident surface and the pitch is 200. // 成. Each linear groove is in the long side of the groove, and the depth of the linear groove that is not closest to the light incident surface side is 10, and the average depth of I is farther from the light incident surface, the line The deeper the groove, the average depth of the linear groove farthest is 32 // m. Method: Using a mold that has reversed the shape, polycarbonate resin "Upiron" HL-4000 (Japan III) The resin plate of the system) is heated to 160 ° C, followed by 30 seconds. Secondly, after cooling to 80 ° C, the pressure is released and then cut off The outer periphery of the obtained molded article is finished and the shape is 'obtained (light guide Α-4). It is made of polycarbonate (stock). 3 mm plate shape 186.5 mmx horizontal 1 8 4.0 mm X horizontal non-ejecting surface side. Roughness Ra = 90〇, θ 1 = m The rule of the interval changes. 〃 m. Linear groove Distance light injection Demolition of 0.3 m m thick engineering plastic 300kN compression ί. Light guide 3. -56- 200825468 . Screen size · 1.8 (light guide size: vertical 40 mm x width 30.5 mm x thickness 0.7 mm, linear groove formation area: vertical 37 mm x width 30 mm, separated by 2.8 mm from the light incident surface, in the light A linear groove is formed on the exit surface side, and the light exit surface side is a smooth surface (surface roughness R a = 10 nm). Linear groove: The profile shape is an isosceles triangle (top angle 90., 0 1 2 45 °), and the linear groove is formed parallel to the light incident surface and spaced by a spacing of 200 // m. Each linear groove is in the longitudinal direction of the groove, and the depth changes irregularly. The average depth of the linear groove closest to the side of the light incident surface is 1. 8 // m. The average depth of the linear groove f - ^ is farther from the light incident surface, and the deeper the linear groove is. The average depth of the linear groove furthest from the light entrance is 3 1 /z m. In the production method, the light guide 3 is obtained by injection molding using a polycarbonate resin "Upiron" HL-4000 (manufactured by Mitsubishi Engineering Plastics Co., Ltd.). (Light guide A-5) Screen size: 17吋 (Light guide size: vertical 280mmx horizontal 349.8mm _ X thickness 6 mm, linear groove formation area: vertical 2 7 5 mm X horizontal 3 4 9 mm, distance from When the light is incident on the inner side of the surface of 2.5 mm, a linear groove is formed on the light non-ejecting surface side, and the light emitting surface side is a smooth surface (surface roughness Ra = 8 nm). Linear groove: The profile shape is an isosceles triangle (top angle 100 。, Θ 1 = 40°), and the linear groove is formed parallel to the light incident surface and spaced by a spacing of 200 // m. Each linear groove is in the longitudinal direction of the groove, and the depth changes irregularly. The linear groove closest to the side of the light incident surface has an average depth of 1 2 // m. The average depth of the linear grooves is farther from the light incident surface and the deeper the linear grooves. The line of the central part -57- 200825468, the average depth of the groove is 3 4 // m. Method: The mold of the 6mm thick polycarbonate resin "Upiron" (registered trademark) HL-4000 (manufactured by Mitsubishi Engineering Plastics Co., Ltd.) is heated to 160t, followed by 500kN. Compress for 30 seconds. Next, after cooling to 80 ° C, the pressure was released and demolding was carried out. After cutting the outer periphery of the obtained molded article, the shape was adjusted to obtain a light guide 3° (light guide A-6) (·screen size: 7吋 (vertical 92mm x width 158mmx thickness 00mm, linear groove formation area: vertical) 88mm x 347mm, a linear groove is formed on the light non-ejecting surface side from the inner side of the light incident surface, and the light emitting surface side smooth surface (surface roughness Ra = 9 nm)). Linear groove: sectional shape system Isosceles dihedral (vertex 1 〇〇., 0 1 = 40 ^ ) 'Linear grooves are formed parallel to the light incident surface and spaced at a spacing of 200 // m. Each linear groove is in the longitudinal direction of the groove. The depth shows an irregular change. (The average depth of the linear groove closest to the light incident side is 1 1 // m. The average depth of the linear groove is farther from the light incident surface, and the deeper the linear groove. The average depth of the linear groove in the center is 3 6 /zm. Method: Use a polycarbonate resin "Upiron" HL-4000 (manufactured by Mitsubishi Engineering Plastics Co., Ltd.) with a mold that reverses the shape. The injection molding was carried out to obtain a plate-shaped light guide 3 having a length of 9 2 mm X and a width of 1 5 8 mm X and a thickness of 3 mm (light guide A-7) -58- 20082 5468 - Screen size: 13.3 inches (light guide size: vertical 186.5mmx horizontal 2 8 9 · 2 8 mm X thickness 0 · 3 mm, linear groove formation area · vertical 1 8 4.0 mm X horizontal 2 8 7 mm, A linear groove is formed on the light non-ejecting surface side from a distance of 2 · 5 mm from the inner side of the light incident surface. The light emitting surface side is a smooth surface (surface roughness Ra of 2 nm). Linear groove: the cross-sectional shape is isosceles The triangle (top angle 1 〇〇., Θ 1 2 40 0 ), the linear groove is formed parallel to the light incident surface and spaced at a spacing of 200 // m. Each linear groove is in the longitudinal direction of the groove, and the depth is not The rule changes. f '· V The average depth of the linear groove closest to the light incident side is 1〇//!! 1. The average depth of the linear groove is farther from the light incident surface, and the deeper the linear groove The average depth of the linear groove farthest from the light entrance surface is 3 2 // m. Method: Using a mold that has reversed the shape, a 3mm thick polycarbonate resin "Upiron" (registered) The resin plate of HL-4000 (made by Mitsubishi Engineering Plastics Co., Ltd.) is heated to 160 ° C, and then compressed at 300 kN for 30 seconds. Secondly, after cooling to 8 (TC, After the pressure was released, the mold was released, and the outer periphery of the obtained molded article was cut to form a light guide 3. (Light guide A-8) Screen size: 1·8 吋 (light guide size: vertical 40 mmx) The horizontal width is 30.5 mmx and the thickness is 0.7 mm. The linear groove forming area is 37 mm in length and 30 mm in width. The distance is 2.8 mm apart from the light incident surface, and a linear groove is formed on the light non-emitting surface side. The light exit surface side is a smooth surface (surface roughness Ra = 8 nm)). Linear groove: The profile shape is an isosceles triangle (apex angle 1 00., 0 1 = -59- 200825468 40°) ‘Linear grooves are formed parallel to the light incident surface and spaced at a spacing of 200 // m. Each linear groove is in the longitudinal direction of the groove, and the depth changes irregularly. The linear groove closest to the side of the light incident surface has an average depth of 2 // m. The average depth of the linear grooves is farther from the light incident surface and the deeper the linear grooves. The average depth of the linear grooves in the central part is 3 1 // m. In the production method, the light guide 3 is obtained by injection molding using a polycarbonate resin "Upiron" HL-4000 (manufactured by Mitsubishi Engineering Plastics Co., Ltd.). For the light guide body, the dimensions, the shape (the linear groove or the linear protrusion), the formation surface of the linear groove, the slope of the light source side of the linear groove 33, and the line perpendicular to the light source are arranged in Table 1. The angle 0 1 is different from the angle 0 2 of the inclined surface of the linear protrusion 3 4 with respect to the light source 1 and the line perpendicular to the light source, the depth 线 1 of the linear groove or the height H2 of the linear protrusion, the linear groove or the line shape The pitch of the protrusions is Ρ. -60- 200825468 [Table 1] Dimensions (吋) Forming surface 01 or 02 (〇) H1 or H2 (Um) P (//m) A-1 17 Linear groove non-ejection surface 45 11 to 33 200 A- 2 7 Linear groove non-ejecting surface 45 10 ~ 36 200 A-3 13.3 Linear groove non-injecting surface 45 10 ~ 32 200 A-4 1.8 Linear groove non-injecting surface 45 1.8 ~ 31 200 A-5 17 Linear groove Non-ejecting surface 40 12 to 34 200 A-6 7 Linear groove non-ejection surface 40 11 to 36 200 A-7 13.3 Linear groove non-ejecting surface 40 10 to 32 200 A-8 1.8 Linear groove non-ejection surface 40 2 ～31 200 In addition, the optical films used in the examples and comparative examples are as follows: (optical film B-1) Shape: an approximately sinusoidal random stripe pattern obtained by optical interference is formed on the surface of the film (average The spacing is 1 5.6 // m, and the average aspect ratio (two average height/average spacing) is 0.63). Method: 10 parts by weight of Adekaoptomer (registered trademark) KRM-2199 (made by Nippon Seiko Chemical Co., Ltd.), Aron Oxetane 〇X Ding-221 (manufactured by Sakamoto East Synthetic Co., Ltd.) 1 part by weight, "Adekaoptomer SP170 (made by Nippon Seiko Chemical Co., Ltd.) 25· 25 parts by weight of the mixture and stirring to obtain a coating liquid. Next, the coating liquid was applied to the surface of the surface shape of the mold so as to have a thickness of the coating film of 50 / / m. After coating, the polyester film is superposed on the coating film. -61 - 200825468 • Film "Lumirror" #l〇〇U34 (manufactured by Toray Co., Ltd.) After applying pressure from the film side, it is bonded. Next, the dimension (iv) is irradiated with ultraviolet rays of a total of 100 mJ /cm 2 from the film surface side, and then released into a film to impart a surface unevenness to the base film. (Optical film B-2) Shape: Cylindrical lens shape (with a spacing of 4 0 // m, a semi-elliptical shape with a height of 50 μm and a width of 50 μm) is assigned to f according to Fig. 19) . Method of manufacture: Except that the mold having reversed the shape is used, it is manufactured by the same method as B-1. (Optical film B - 3 ) Shape: The long axis 200 // m, the short axis 20 /zm, and the high g spindle-shaped protrusions are arranged on the surface of the film (refer to Fig. 20). The method is: except that the mold having the shape reversed is used as In addition, it is manufactured by the same method as B-1. (Optical Film B-4) Shape: The rod-shaped particles were arranged in one direction in the inside of the film. The average short diameter is 3//m and the average long diameter is 500//m. Method: 94% by volume is used as a light diffusing component, which is relative to polyethylene terephthalate (PET) ^ 10m 〇 1% of isophthalic acid component, relative to diol unit cyclohexane The polyester resin (β, which is copolymerized with the methanol component, is used to carry out the film surface in the longitudinal direction of the light 1 on one side of the mold in this state (the mold is used in half of t 20 μm). The mold is used to > The main resin of the rod-shaped particles is an acid unit of 10 m ο 1 %, TB : 225 -62 - 200825468 • °c ), and 6 vol% of polymethylpentene as a light diffusing element ( Japan's Mitsui Chemicals Co., Ltd.), a mixture of nine pellets supplied to the main extruder. Further, PET (melting point TA: 265 t ) was supplied to this sub-extruder using a sub-extruder different from the main extruder. Next, the thickness ratio of the surface layer supplied to both sides of the component layer of the main extruder and the component layer supplied to the sub-extruder becomes a constituent layer of the sub-extruder: component layer of the main extruder: sub-extruder The co-extrusion of the molten three-layered layer was carried out by the component layer = 1: 8:1. The resin to be extruded was cooled by a static electricity application method on a casting drum rotated at a speed f 2 of the extrusion speed to obtain a three-layer laminated sheet. Stretched 3.2 times along the long side of the laminated sheet at a temperature of 87 ° C, and then, by a tenter, through a preheating zone of 9 5 t, stretching 3.4 times in the width direction at 110 ° C . Further, by heat-treating the heat treatment temperature Th at 2 3 5 ° C for 30 seconds, a film having a thickness of 180 / z m contained in the traveling direction of the film was obtained in the inner rod-shaped particles. (Optical film B-5) (1 Using a diffusion film made of Toray Sehan) TEXCELL" TDS127. (Optical film B-6) Using a diffusion film UTEII manufactured by Millea Nanotec (Optical film B-7) Shape: on one side The semi-spindle protrusions of the long axis 3 0 // m, the short axis 2 0 // m, and the height 2 0 // m are arranged (refer to Fig. 2 1). Method: except for the mold which has reversed the shape It is manufactured by the same method as B-1 except for use as a mold. -63- 200825468 . (Optical film B-8) Using a diffusion film "TEXCELL" TDA128 by Toray Sehan. (Optical film B-9) Using Kimoto ( Diffusion film DX2 manufactured by the company) (Optical film C-1) BEFIII90/50T made of 3M. (Optical film C-2) The film THIN-T2 made by Mi lie a Nano tec. c, (Optical film) C-3) Shape: 稜鏡 stripes (apex angle 0 3 = 100°, pitch 50 μ m, height 2 \ β m). Method: The mold that has reversed the shape (280mm x 350mm) and 0.2 Mm thick polycarbonate resin "Upiron" HL-4000 (Japan Mitsubishi Engineering Plastics Co., Ltd.) resin plate is heated to 1 60 ° C, then The film was compressed at 500 kN for 30 seconds. Next, after cooling to 80 ° C, the pressure I was released and then released to obtain an optical film. For the optical film, the maximum 値Dmax and minimum 値D mi η of the transmitted half-twisted web were obtained. , D ma X / D mi η, total light reflectance, haze, apex angle 0 of the cymbal, spacing of 稜鏡, and height of 稜鏡 are shown in Tables 2 and 3. -64- 200825468 [Table 2]

Dmax (°) Dmin (°) Dmax/ Dmin 全部光線反射率 (%) 霧度 (%) B-1 29.4 1.6 18.4 74 82 B-2 23.2 1.8 12.9 52 83 B-3 24.0 2.8 8.6 79 88 B-4 21.8 4.2 5.2 89 71 B-5 12.1 12.1 1.0 72 86 B-6 5.4 5.4 1.0 64 85 B-7 26.0 16.3 1.6 63 93 B-8 5.2 5.2 1.0 84 86 B-9 17.0 17.0 1.0 67 90 【表3】 03 (°) 間距 (//m) 高度 (“m) C-1 90 50 30 C-2 92 32 15 C-3 88 50 30 C-4 100 50 21 (實施例1 - 1 ) 使未形成線狀溝之面成爲觀察側者側之方式來設置導光體A-1，分別將各二支冷陰極螢光燈（以下，稱爲CCFL) 配置於相對的二個光射入面，於其周圍設 -65- 200825468 置” Lumirror” E6SV(Toray (股份）製）作爲反射板。於導光體 3之非觀察者側設置反射片” Lumirror” E6SL (Toray (股份）製）。於導光體3之觀察者側，以使作爲第1光學薄膜之異方向擴散性爲最大的方向與導光體3之線狀溝的長邊方向成爲平行（亦即，β 5 = 0° )之方式來設置Β -1。於第1光學薄膜Β -1之上，以使作爲第2光學薄膜之稜鏡長邊方向與光學薄膜Β -1之異方向擴散性爲最大的方向成爲平行（亦即，0 6 = 0。）之方式來設置C-1後而製 f ： % 作面光源。還有，第1光學薄膜、第2光學薄膜任一種均使凹凸面成爲觀察者側之方式來加以設置。將電源電壓 12V供應至此面光源後而使CCFL亮燈。亮燈10分鐘後，測定面光源面內之25點亮度（參照第18圖（a ))時，中心亮度爲6 820cd/m2 (評估A )、均勻度U爲82% (評估A)，得知具優越之中心亮度、均勻度 U。另外，測定從面光源中央部之射出角分布後’視野角係 ^ 縱向31。（評估A)、橫向46。（評估A)，得知顯示良好之視野角特性（參照表4 )。 (實施例1-2 ) 除了將B-2作爲第1光學薄膜使用以外，進行相同於實施例1 -1之方式而製作面光源。亮燈10分鐘後，測定面光源面內之25點亮度（參照第18圖（a))時，中心亮度爲6950cd/m2 (評估A)、均勻度U爲8 1 % (評估A)，得知具優越之中心亮度、均勻度 -66- 200825468 . U °另外，測定從面光源中央部之射出角分布後，視野角係縱向3 0。（評估A )、橫向4 5。（評估A )，得知顯示良好之視野角特性（參照表4 )。 (實施例1 - 3 ) 除了將B - 3作爲第1光學薄膜使用以外，進行相同於實施例1 -1之方式而製作面光源。亮燈10分鐘後，測定面光源面內之25點亮度（參照第18圖（a))時，中心亮度爲6 690c d/m2 (評估C )、均句Dmax (°) Dmin (°) Dmax/ Dmin Total light reflectance (%) Haze (%) B-1 29.4 1.6 18.4 74 82 B-2 23.2 1.8 12.9 52 83 B-3 24.0 2.8 8.6 79 88 B-4 21.8 4.2 5.2 89 71 B-5 12.1 12.1 1.0 72 86 B-6 5.4 5.4 1.0 64 85 B-7 26.0 16.3 1.6 63 93 B-8 5.2 5.2 1.0 84 86 B-9 17.0 17.0 1.0 67 90 [Table 3] 03 (°) Spacing (//m) Height ("m) C-1 90 50 30 C-2 92 32 15 C-3 88 50 30 C-4 100 50 21 (Example 1 - 1 ) The light guide body A-1 is disposed so as to face the side of the groove, and each of the two cold cathode fluorescent lamps (hereinafter referred to as CCFL) is disposed on the opposite two light incident surfaces. -65- 200825468 "Lumirror" E6SV (manufactured by Toray Co., Ltd.) is used as a reflector. A reflection sheet "Lumirror" E6SL (made by Toray Co., Ltd.) is provided on the non-observer side of the light guide 3. On the observer side of the third aspect, the direction in which the diffusivity in the different direction of the first optical film is maximized is parallel to the longitudinal direction of the linear groove of the light guide 3 (that is, β 5 = 0°). Set Β -1. On the 1st optical thin Β -1 is set so that the direction in which the long side of the second optical film and the direction in which the optical film Β -1 is diffused in the opposite direction are parallel (that is, 0 6 = 0) In the case of C-1, f: % is a surface light source. Further, any of the first optical film and the second optical film is provided such that the uneven surface is on the observer side. After the power supply voltage 12V is supplied to the surface light source, The CCFL is turned on. After the light is turned on for 10 minutes, the brightness of the surface of the surface light source is measured at 25 points (refer to Fig. 18(a)), the center brightness is 6 820 cd/m2 (evaluation A), and the uniformity U is 82%. (Evaluation A), it was found that the center brightness and the uniformity U were excellent. The measurement was made from the distribution angle of the central portion of the surface light source, and then the viewing angle system was longitudinally 31 (evaluation A) and lateral direction 46. (Evaluation A) It was found that the viewing angle characteristics were good (see Table 4). (Example 1-2) A surface light source was produced in the same manner as in Example 1-1 except that B-2 was used as the first optical film. After lighting for 10 minutes, measure the brightness at 25 o'clock in the surface of the surface light source (refer to Fig. 18 (a)), the center brightness 6950cd/m2 (evaluation A), uniformity U is 8 1 % (evaluation A), and it is known that the center brightness and uniformity are superior -66- 200825468 . U ° In addition, after measuring the distribution of the exit angle from the central portion of the surface light source The viewing angle is 3 0 in the longitudinal direction. (Evaluation A), horizontal 4 5 . (Evaluation A), it was found that the viewing angle characteristics were good (refer to Table 4). (Examples 1 to 3) A surface light source was produced in the same manner as in Example 1-1 except that B-3 was used as the first optical film. After lighting for 10 minutes, the brightness at 25 points in the surface of the surface light source was measured (refer to Fig. 18(a)), and the center brightness was 6 690 c d/m2 (evaluation C).

C 度U爲8 5 % (評估A )，得知具優越之中心亮度、均勻度 U。另外，測定從面光源中央部之射出角分布後，視野角係縱向32° (評估A )、橫向47。（評估A )，得知顯示良好之視野角特性（參照表4 )。 (實施例1 - 4 ) 除了將B-4作爲第1光學薄膜使用以外，進行相同於實施例1 -1之方式而製作面光源。〔亮燈10分鐘後，測定面光源面內之25點亮度（參照第18圖（a ))時，中心亮度爲6510cd/m2 (評估D )、均g 度U爲8 3 % (評估A )，得知具優越之中心亮度、均句度 U。另外’測疋從面光源中央部之射出角分布後，視野角係縱向3 2 ° ( §平估A ) 、f頁向4 7 ° ( g平估A )，得知顯示良好之視野角特性（參照表4 )。 (實施例1-5 ) 除了將C- 2作爲第2光學薄膜使用以外，進行相同於 -67- 200825468 ，實施例1 -1之方式而製作面光源。The C degree U is 85 % (evaluation A), and it is known that the center brightness and uniformity U are superior. Further, after measuring the distribution of the exit angle from the central portion of the surface light source, the viewing angle was 32° in the longitudinal direction (evaluation A) and lateral direction 47. (Evaluation A), it was found that the viewing angle characteristics were good (refer to Table 4). (Examples 1 to 4) A surface light source was produced in the same manner as in Example 1-1 except that B-4 was used as the first optical film. [After lighting for 10 minutes, when measuring the brightness at 25 o'clock in the surface of the surface light source (refer to Fig. 18 (a)), the center luminance is 6510 cd/m2 (evaluation D), and the uniformity g is 8 3 % (evaluation A) , to know that the center brightness is superior and the uniformity is U. In addition, after measuring the distribution angle of the exit from the central part of the surface light source, the viewing angle is 3 2 ° in the longitudinal direction (§A), and the f-page is 4 7 ° (g is estimated), and it is known that the viewing angle is good. (Refer to Table 4). (Example 1-5) A surface light source was produced in the same manner as in -67-200825468, Example 1-1, except that C-2 was used as the second optical film.

亮燈10分鐘後，測定面光源面內之25點亮度（矣M 第18圖（a ))時，中心亮度爲6740cd/m2 (評估B )、 Λ 均句度U爲8 2 % (評估A )，得知具優越之中心亮度、均_ p U。另外，測定從面光源中央部之射出角分布後，視# 縱向3 1 ° (評估A )、橫向45 ° (評估A )，得知顯希良好之視野角特性（參照表4 )。 (實施例1-6) C…i 除了將C-3作爲第2光學薄膜使用以外，進行相同於實施例1 -1之方式而製作面光源。亮燈10分鐘後，測定面光源面內之25點亮度（參照第18圖（a ))時，中心亮度爲6720cd/m2 (評估Β )、均自度U爲8 0 % (評估A )，得知具優越之中心亮度、均句度 U。另外，測定從面光源中央部之射出角分布後，視野角係縱向3 0 ° (評估A )、橫向4 4 ° (評估A )，得知顯示良好 ΐ 之視野角特性（參照表4 )。 (實施例1-7 ) 除了將C-4作爲第2光學薄膜使用以外，進行相同於實施例1 -1之方式而製作面光源。亮燈10分鐘後，測定面光源面內之25點亮度（參照第18圖（a ))時，中心亮度爲6505 cd/m2 (評估D )、均勻度U爲8 0 % (評估A)，得知具優越之中心亮度、均勻度 U。另外，測定從面光源中央部之射出角分布後’視野角係 -68- 200825468 . 縱向34° (評估A )、橫向46。（評估A )，得知顯示良好之視野角特性（參照表4 )。 (實施例1 - 8 ) 將C-1作爲第2光學薄膜使用，除了使第1光學薄膜之異方向擴散性爲最大的方向與第2光學薄膜之棱鏡長邊方向成爲垂直（亦即，06=90。）之方式來予以配置以外，進行相同於實施例1 -1之方式而製作面光源。亮燈10分鐘後，測定面光源面內之25點亮度（參照 ζ ) 第18圖（a))時，中心亮度爲6500cd/m2 (評估D)、均勻度U爲7 5 % (評估A)，得知具優越之中心亮度、均勻度 U。另外，測定從面光源中央部之射出角分布後，視野角係縱向48° (評估A)、橫向30。（評估A)，得知顯示良好之視野角特性（參照表4 )。 (實施例1 - 9 ) 除了使作爲第1光學薄膜之異方向擴散性爲最大的方 ^ / 向與導先體3之線狀溝的長邊方向成爲0 5"=5°之方式來設置B -1以外，進行相同於實施例1 -1之方式而製作面光源。亮燈10分鐘後，測定面光源面內之25點亮度（參照弟18圖（a))時’中心売度爲6780cd/m2 (評估B)、均勻度U爲8 2 % (評估A )，得知具優越之中心亮度、均勻度 U。另外，測定從面光源中央部之射出角分布後，視野角係縱向3 2 ° (評估A )、橫向4 5。（評估A )，得知顯示良好 -69- 200825468 . 之視野角特性（參照表4 )。 (實施例1 -1 0 ) 除了使作爲第1光學薄膜之異方向擴散性爲最大的方向與導光體3之線狀溝的長邊方向成爲0 5= 1〇°之力式來設置B -1以外，進行相同於實施例1 -1之方式而製作面光源。亮燈10分鐘後，測定面光源面內之25點亮度（參照第18圖（a))時，中心亮度爲667 0cd/m2 (評估C)、均勻 η 度U爲8 1 % (評估A)，得知具優越之中心亮度、均勻度 U。另外，測定從面光源中央部之射出角分布後’視野角係縱向3 3。（評估A )、橫向44。（評估A )，得知顯示良好之視野角特性（參照表4 )。 (實施例2 ) 使未形成線狀溝之面成爲觀察側者側之方式來設置導光體 A-1，分別將各一支CCFL配置於相對的二個光射入 I, 面，於其周圍設置” Lumirror” E6SV ( Toray (股份）製）作爲反射板。於導光體 3之非觀察者側設置反射片” Lumhror” E6SL ( Toray (股份）製）。於導光體3之觀察者側，以使作爲第1光學薄膜之異方向擴散性爲最大的方向與導光體3之線狀溝的長邊方向成爲平行（亦即， 05=0°)之方式來設置B-1。於光學薄膜B-i之上，以使作爲第2光學薄膜之稜鏡長邊方向與光學薄膜B-1之異方向擴散性爲最大的方向成爲平行（亦即，Θ 6二0 ° )之方式 -70- 200825468 來設置C-1後而製作面光源。還有，第1光學薄膜、第2 光學薄膜任一種均使凹凸面成爲觀察者側之方式來加以設置。將電源電壓12V供應至此面光源後而使CCFL亮燈。亮燈10分鐘後，測定面光源面內之25點亮度（參照第18圖（a ))時，中心亮度爲7 3 5 0cd/m2 (評估A )、均句度U爲82% (評估A )，得知具優越之中心亮度、均勻度 U。另外，測定從面光源中央部之射出角分布後，視野角係縱向30° (評估A)、橫向45° (評估A)，得知顯示良好 " 之視野角特性（參照表4 )。 (實施例3 ) 使未形成線狀溝之面成爲觀察側者側之方式來設置導光體A-3，平行於光射入面來配置49個發光二極體（以下，稱爲LED )，於其周圍設置” Lumirror” E6SV ( Toray (股份）製）作爲反射板。於導光體3之非觀察者側設置反射片” Lumirror” E6SL(Toray (股份）製）。於導光體3之 I 觀察者側，以使作爲第1光學薄膜之異方向擴散性爲最大的方向與導光體3之線狀溝的長邊方向成爲平行（亦即， 05=0°)之方式來設置B-1。於光學薄膜B-1之上，以使作爲第2光學薄膜之稜鏡長邊方向與光學薄膜B-1之異方向擴散性爲最大的方向成爲平行（亦即，0 6 = 0 ° )之方式來設置C-1後而製作面光源。還有，第1光學薄膜、第2 光學薄膜任一種均使凹凸面成爲觀察者側之方式來加以設置。將電源電壓15V供應至此面光源後而使LED亮燈。 -71 - 200825468 亮燈10分鐘後，測定面光源面內之25點亮度（參照第18圖（a ))時，中心亮度爲4320cd/m2 (評估A )、均勻度U爲8 2 % (評估A)，得知具優越之中心亮度、均勻度 U。另外，測定從面光源中央部之射出角分布後，視野角係縱向3 0 ° (評估A )、橫向4 6 ° (評估A )，得知顯示良好之視野角特性（參照表4 )。 (實施例4 -1 ) 將未形成線狀溝之面成爲觀察側者側之方式來設置導 f % 光體A-4，平行於光射入面來配置3個LED，於其周圍設置” Lumirror” E6SV ( Toray (股份）製）作爲反射板。於導光體 3之非觀察者側設置反射片” Lumirror” E6SL (Toray (股份）製）。於導光體3之觀察者側，以使作爲第1光學薄膜之異方向擴散性爲最大的方向與導光體3之線狀溝的方向成爲平行（亦即，0 5 = 0 ° )之方式來設置 B-1。於光學薄膜B-1之上，以使作爲第2光學薄膜之稜鏡 I 長邊方向與光學薄膜B -1之異方向擴散性爲最大的方向成爲平行（亦即，06=0°)之方式來設置C-1而製作面光源。還有，第1光學薄膜、第2光學薄膜任一者均使凹凸面成爲觀察者側之方式來加以設置。將電源電壓3 . 3 V供應至此面光源後而使LED亮燈。亮燈1 0分鐘後，測定面光源面內之9點亮度（參照第 18圖（b ))時，中心亮度爲6470cd/m2 (評估A )、均勻度 U爲8 2 % (評估A )，得知具優越之中心亮度、均勻度U。 -72- 200825468 . 另外’測定\從面光源中央部之射出角分布後，視野角係縱向3 1 ° (評估a )、橫向45。（評估A )，得知顯示良好之視野角特性（參照表5 )。 (實施例4 - 2〜4 -1 0 ) 於實施例4-1之導光體上，重疊相同於實施例1-2〜 1-10之薄膜而製作面光源。將電源電壓3. 3V供應至此面光源後而使LED亮燈。亮燈1 〇分鐘後，測定面光源面內之9點亮度（參照第〇 1 8圖（b ))後，得知均具優越之中心亮度、均勻度U。另外’測定從面光源中央部之射出角分布時，得知均顯示良好之視野角特性（參照表5)。 (實施例5 -1 ) 將未形成線狀溝之面成爲觀察側者側之方式來設置導光體A-5，分別將各二支CCFL配置於相對的二個光射入面，於其周圍設置” Lumirror” E6SV(Toray (股份）製） (j 作爲反射板。於導光體 3之非觀察者側設置反射片” Lumirror” E6SL ( Toray (股份）製）。於導光體3之觀察者側，以使作爲第1光學薄膜之異方向擴散性爲最大的方向與導光體3之線狀溝的方向成爲平行（亦即，0 5 = 0°)之方式來設置B-1。於其上，設置B-6作爲第2光學薄膜後而製作面光源。還有，第1光學薄膜、第2光學薄膜任一者均使凹凸面成爲觀察者側之方式來加以設置。將電源電壓12V供應至此面光源後而使CCFL亮燈。 -73- 200825468 亮燈10分鐘後，測定面光源面內之2 5點亮度（參照第18圖（a))時，中心亮度爲5510cd/m2、均勻度〇爲82 %，得知具優越之中心亮度、均勻度U。另外，_定從面光源中央部之射出角分布後，視野角係縱向3 9。、橫向4 1 ，得知顯示良好之視野角特性（參照表6 )。 (實施例5 - 2 ) 除了將B - 2作爲第1光學薄膜使用以外，進行相同於實施例5 -1之方式而製作面光源。亮燈10分鐘後，測定面光源面內之25點亮度（參照桌18圖）時’中心売度爲5730cd/m2、均勻度U爲81%，得知具優越之中心亮度、均勻度U。另外，測定從面光源中央部之射出角分布後，視野角係縱向3 8。、橫向4 0。，得知顯示良好之視野角特性（參照表6 ) (實施例5 - 3 ) 除了將B - 3作爲第1光學薄膜使用以外，進行相同於實施例5 -1之方式而製作面光源。亮燈10分鐘後，測定面光源面內之2 5點亮度（參照第18圖（a))時，中心亮度爲5440cd/m2、均勻度u爲84 %，得知具優越之中心亮度、均勻度U。另外，測定從面光源中央部之射出角分布後，視野角係縱向3 9。、橫向4 0。，得知顯示良好之視野角特性（參照表6 ) (實施例5-4 ) 除了將B-4作爲第1光學薄膜使用以外，進行相同於 -74- 200825468 . 實施例5 -1之方式而製作面光源。亮燈10分鐘後，測定面光源面內之2 5點亮度（參第18圖（a ))時，中心亮度爲5300cd/m2、均勻度U爲 %，得知具優越之中心亮度、均勻度U。另外，測定從光源中央部之射出角分布後，視野角係縱向40°、橫向43 得知顯示良好之視野角特性（參照表6 ) (實施例5-5 ) 除了將B-7作爲第2光學薄膜使用以外，進行相同 η 實施例5-1之方式而製作面光源。還有，光學薄膜Β-7 使其異方向擴散性爲最大之方向與光學薄膜Β -1之異方擴散性爲最大之方向成爲垂直（亦即，0 6 = 90° )之方來加以設置。亮燈10分鐘後，測定面光源面內之2 5點亮度（參第18圖（a ))時，中心亮度爲5250cd/m2、均勻度U爲 %，得知具優越之中心亮度、均勻度U。另外，測定從 I) 光板中央部之射出角分布後，視野角係縱向40。、橫向42 得知顯示良好之視野角特性（參照表6 ) (實施例5-6 ) 除了將B - 8作爲第2光學薄膜使用以外，進行相同實施例5 -1之方式而製作面光源。亮燈10分鐘後，測定面光源面內之2 5點亮度（參弟18圖（a))日寸’中心売度爲5370cd/m2、均句度U爲 %，得知具優越之中心亮度、均勻度U。另外，測定從昭 j \ w 82 面於係向式照 85 導於照 82 面 •75- 200825468 • 光源中央部之射出角分布後，視野角係縱向4 1。、橫向4 3 得知顯示良好之視野角特性（參照表6 ) (實施例5 - 7 ) 除了將B-9作爲第2光學薄膜使用以外，進行相同實施例5 -1之方式而製作面光源。亮燈10分鐘後，測定面光源面內之2 5點亮度（參第18圖（a))時，中心亮度爲5210cd/m2、均勻度U爲 Γ %，得知具優越之中心亮度、均勻度U。另外，測定從光源中央部之射出角分布後，視野角係縱向42。、橫向44 得知顯示良好之視野角特性（參照表6 ) (實施例5 - 8 ) 除了使作爲第1光學薄膜之異方向擴散性爲最大之向與導光體3之線狀溝之長邊方向成爲 05=5。之方式設置Β -1以外，進行相同於實施例5 -1之方式而製作面源。、亮燈1 〇分鐘後，測定面光源面內之25點亮度（參第18圖（a))時，中心亮度爲5470cd/m2、均勻度U爲 %，得知具優越之中心亮度、均勻度U。另外，測定從光源中央部之射出角分布後，視野角係縱向40。、橫向40 得知顯示良好之視野角特性（參照表6 )。 (實施例5-9 ) 除了使作爲第1光學薄膜之異方向擴散性爲最大之向與導光體3之線狀溝之長邊方向成爲05=1〇。之方式於照 83 面方來光照 82 面方來 -76- 200825468 • 設置B -1以外，進行相同於實施例5 -1之方式而製作面源。売燈10分鐘後’測定面光源面內之2 5點亮度（參第18圖（a))時，中心亮度爲5350cd/m2、均勻度U爲 % ’得知具優越之中心亮度、均勻度U。另外，測定從光源中央部之射出角分布後，視野角係縱向40。、橫向40 得知顯示良好之視野角特性（參照表6)。 (實施例6 ) f 使未形成線狀溝之面成爲觀察側者側之方式來設置光體A-6，在相對的二光射入面上分別各配置一支CCFL 於其周圍設置” Lumirror” E6S V ( Toray (股份）製）作反射板。於導光體 3之非觀察者側設置反片 ” Lumirror” E6SL ( Toray (股份）製）。於導光體 3 觀察者側，以使作爲第1光學薄膜之異方向擴散性爲最的方向與導光體3之線狀溝的長邊方向成爲平行（亦即 Θ5=0。）之方式來設置B-1。於光學薄膜B-1之上，設作爲第2光學薄膜之Β-6而製作面光源。還有，第1光薄膜、第2光學薄膜任一者均使凹凸面成爲觀察者側之式來加以設置。將電源電壓1 2 V供應至此面光源後而 CCFL亮燈。亮燈10分鐘後，測定面光源面內之25點亮度（參第18圖（a))時，中心亮度爲5970cd/m2、均勻度U爲 %，得知具優越之中心亮度、均勻度U。另外，測定從光照 8 1 面導爲射之大置學方使照 82 導 -77- 200825468 I 光體中央部之射出角分布後，視野角係縱向3 9。、橫向4 1 得知顯示良好之視野角特性（參照表6 )。 (實施例7 ) 使未形成線狀溝之面成爲觀察側者側之方式來設置光體A-7，平行於光射入面來配置49個LED，於其周圍置” Lumirror” E6SV ( Toray (股份）製）作爲反射板。非觀察者側設置反射片” Lumirror” E6SL ( Toray (股份製）。於導光體3之觀察者側，以使作爲第1光學薄膜 r 異方向擴散性爲最大的方向與導光體3之線狀溝的長邊向成爲平行（亦即，05=0。）之方式來設置B-1。於光薄膜B-1之上，設置作爲第2光學薄膜之B-6而製作面源。還有，第1光學薄膜、第2光學薄膜任一者均使凹面成爲觀察者側之方式來加以設置。將電源電壓1 5 V供至此面光源後而使LED亮燈。亮燈10分鐘後，測定面光源面內之2 5點亮度（參 (, 第18圖（a))時，中心亮度爲3450cd/m2、均勻度U爲 %，得知具優越之中心亮度、均勻度U。另外，測定從光源中央部之射出角分布後，視野角係縱向40。、橫向41 得知顯示良好之視野角特性（參照表6 )。 (實施例8 ) 使未形成線狀溝之面成爲觀察側者側之方式來設置光體A-8，平行於光射入面來配置3個LED，於其周圍置” Lumirroi·” E6SV ( Toray (股份）製）作爲反射板。導設於 ) 之方學光凸應照 82 面導設於 -78- 200825468 、導光體 3之非觀察者側設置反射片” Lunnrror” E6SL (Toray (股份）製）。於導光體3之觀察者側，以使作爲第1光學薄膜之異方向擴散性爲最大的方向與導光體3之線狀溝的長邊方向成爲平行（亦即，0 5 = 0° )之方式來設置B-1。於光學薄膜B-1之上，設置作爲第2光學薄膜之 B-6而製作面光源。還有，第1光學薄膜、第2光學薄膜任一者均使凹凸面成爲觀察者側之方式來加以設置。將電源電壓3.3V供應至此面光源後而使LED亮燈。 f ^ 亮燈1 0分鐘後，測定面光源面內之9點亮度（參照第 18圖（b))時，中心亮度爲5340cd/m2、均勻度U爲82%，得知具優越之中心亮度、均勻度U。另外，測定從面光源中央部之射出角分布後，視野角係縱向39°、橫向41°，得知顯示良好之視野角特性（參照表7 )。 (實施例8-2〜8-9 ) 於實施例8 -1之導光體上重疊相同於實施例5 · 2〜5 - 9 I 之薄膜而製作面光源。將電源電壓3.3 V供應至此面光源後而使LED亮燈。亮燈1 0分鐘後，測定面光源面內之9點亮度（參照第 1 8圖（b ))時，得知具優越之中心亮度、均勻度U。另外，測定從面光源中央部之射出角分布後，得知任一例均顯示 •良好之視野角特性（參照表7 )。 (比較例1 -1 ) 除了將B-5作爲第1光學薄膜使用以外，進行相同於 -79- 200825468 . 實施例1 -1之方式而製作面光源。亮燈10分鐘後，測定面光源面內之25點亮度（參照第18圖（a))時，中心亮度爲6210cd/m2、均勻度U爲81 %。另外，測定從面光源中央部之射出角分布後，視野角係縱向3 1 °、橫向45 °，得知雖然可以得到良好之均勻度U、視野角特性，但是中心亮度爲低的（參照表4 )。 (比較例1-2 ) 除了將B-6作爲第1光學薄膜使用以外，進行相同於實施例1 -1之方式而製作面光源。亮燈10分鐘後，測定面光源面內之25點亮度（參照第18圖（a))時，中心亮度爲6170cd/m2 (評估E)、均勻度U爲84 % (評估A )。另外，測定從面光源中央部之射出角分布後，視野角係縱向32° (評估A )、橫向45。（評估A )，得知雖然可以得到良好之均勻度U、視野角特性，但是中心売度爲低的（參照表4 )。 I (比較例1 - 3 ) 除了將B-7作爲第1光學薄膜使用以外，進行相同於實施例1 -1之方式而製作面光源。亮燈10分鐘後，測定面光源面內之25點亮度（參照第18圖（a ))時，中心亮度爲5 960cd/m2 (評估E )、均勻度U爲8 5 % (評估A)。另外，測定從面光源中央部之射出角分布後，視野角係縱向3 1。（評估A )、橫向46。（評估A )，得知雖然可以得到良好之均勻度U、視野角特性， -80- 200825468 • 但是中心亮度爲低的（參照表4 ) ° (比較例1-4 ) 除了使第1光學薄膜之異方向擴散性爲最大之方向與導光體線狀溝之長邊方向成爲垂直（亦即，Θ 5 = 9 0。）之方式來設置B - 1以外，進行相同於實施例1 -1之方式而製作面光源。亮燈10分鐘後，測定面光源面內之2 5點亮度（參照第1 8圖（a ))時，中心亮度爲5 6 8 0 c d / m2 (評估e )、均勻 ( 一度U爲84% (評估A )。另外，測定從面光源中央部之射出角分布後’視野角係縱向3 2 ° (評估A )、橫向4 7。（評估A )，得知雖然可以得到良好之均勻度U、視野角特性，但是中心亮度爲低的（參照表4 )。 (比較例1 - 5 ) 除了使第1光學薄膜之異方向擴散性爲最大之方向與導光體線狀溝之長邊方向成爲垂直（亦即，0 5= 90。）之 (方式來設置B - 2以外’進行相同於實施例1 _丨之方式而製作面光源。亮燈10分鐘後’測定面光源面內之2 5點亮度（參照第18圖（a ))時，中心亮度爲6〇30cd/m2 (評估E )、均勻度U爲8 3 % (評估A )。另外，測定從面光源中央部之射出角分布後’視野角係縱向3 1。（評估A )、橫向4 6。（評估A )’得知雖然可以得到良好之均勻度u、視野角特性，但是中心売度爲低的（參照表4 )。 -81- 200825468 . (比較例1 - 6 ) 除了使第1光學薄膜之異方向擴散性爲最大之方向與導光體線狀溝之長邊方向成爲垂直（亦即，0 5二90。）之方式來設置B - 3以外，進行相同於實施例1 -1之方式而製作面光源。亮燈10分鐘後，測定面光源面內之2 5點亮度（參照第18圖（a))時，中心亮度爲5790cd/m2 (評估E)、均勻度U爲85% (評估a )。另外，測定從面光源中央部之射 Γ' 出角分布後，視野角係縱向3 2。（評估.A )、橫向4 7。（評估A )，得知雖然可以得到良好之均勻度u、視野角特性，但是中心壳度爲低的（參照表4 )。 (比較例1 - 7 ) 除了使第1光學薄膜之異方向擴散性爲最大之方向與導光體3之線狀溝之長邊方向成爲0 5 = 20。之方式來設置 B -1以外，進行相同於實施例1 -1之方式而製作面光源。 [；亮燈1 〇分鐘後，測定面光源面內之2 5點亮度（參照第18圖（a))時，中心亮度爲6490cd/m2 (評估E)、均勻度U爲8 0 % (評估A)。另外，測定從面光源中央部之射出角分布後，視野角係縱向3 5。（評估A )、橫向4 2。（評估A )，得知雖然可以得到良好之均勻度U、視野角特性，但是中心亮度爲低的。 (比較例2 ) 除了將B - 5作爲第丨光學薄膜使用以外，進行相同於 -82- 200825468 ，實施例2之方式而製作面光源。亮燈10分鐘後，測定面光源面內之2 5點亮度（參照第18圖（a))時，中心亮度爲6710cd/m2 (評估E)、均句度U爲84 % (評估A )。另外，測定從面光源中央部之射出角分布後，視野角係縱向3 1。（評估A )、橫向4 6。（評估A )’得知雖然可以得到良好之均勻度u、視野角特性，但是中心亮度爲低的（參照表4 )。 (比較例3 ) (' 除了將B - 5作爲第丨光學薄膜使用以外，進行相同於實施例3之方式而製作面光源。亮燈10分鐘後，測定面光源面內之2 5點亮度（參照第1 8圖（b ))時，中心亮度爲3 790cd/m2 (評估E )、均勻度U爲8 4 % (評估A )。另外，測定從面光源中央部之射出角分布後’視野角係縱向3 1。（評估A )、橫向4 6。（評估A )，得知雖然可以得到良好之均勻度u、視野角特性， ^ 但是中心亮度爲低的（參照表4 )。 (比較例4-1 ) 除了將B - 5作爲第1光學薄膜使用以外，進行相同於實施例4之方式而製作面光源。亮燈1 〇分鐘後’測定面光源面內之9點亮度（參照第 18圖（b))時，中心亮度爲5760cd/m2 (評估E)、均勻度 U爲84% (評估A )。另外，測定從面光源中央部之射出角分布後’視野角係縱向3 0。（評估A )、橫向4 5。（評估 -83- 200825468 • A )，得知雖然可以得到良好之均勻度u、視野角特性，但是中心亮度爲低的（參照表5 )。 (比較例4 - 2〜4 - 7 ) 於實施例4-1之導光體上重疊相同於比較例1_2〜1-7 之薄膜而製作面光源。將電源電壓3.3 V供應至此面光源後而使LED亮燈。亮燈1 0分鐘後，測定面光源面內之9點亮度（參照第 1 8圖（b ))、從面光源中央部之射出角分布時，得知雖然可以得到良好之均勻度U、視野角特性，但是中心亮度爲低的（參照表5 )。 (比較例5 -1 ) 除了將B - 6作爲第1光學薄膜使用以外，進行相同於實施例5 -1之方式而製作面光源。亮燈10分鐘後，測定面光源面內之2 5點亮度（參照弟18圖（a))時’中心売度爲5150cd/m2、均勻度U爲85 I，％。另外，測定從面光源中央部之射出角分布後，視野角係縱向42。、橫向45。，得知雖然可以得到良好之均勻度U、視野角特性，但是中心亮度爲低的（參照表6 )。 (比較例5 - 2 ) 除了將B - 8作爲第1光學薄膜使用、將B - 8作爲第2 光學薄膜使用以外，進行相同於實施例5 -1之方式而製作面光源。亮燈10分鐘後，測定面光源面內之25點亮度（參照 -84- 200825468 . 第18圖（a))時，中心亮度爲4100cd/m2、均勻度U爲84 %。另外，測定從面光源中央部之射出角分布後，視野角係縱向4 1。、橫向45。，得知雖然可以得到良好之均勻度U、視野角特性，但是中心亮度爲低的（參照表6 )。 (比較例5 - 3 ) 除了將B-9作爲第1光學薄膜使用、將B-9作爲第2 光學薄膜使用以外，進行相同於實施例5 - 1之方式而製作 f 面光源。亮燈10分鐘後，測定面光源面內之2 5點亮度（參照第18圖（a))時，中心亮度爲43 5 0cd/m2、均勻度U爲84 %。另外，測定從面光源中央部之射出角分布後，視野角係縱向42。、橫向45°，得知雖然可以得到良好之均勻度u、視野角特性，但是中心亮度爲低的（參照表6 )。 (比較例5-4 ) 除了使第1光學薄膜之異方向擴散性爲最大的方向與 ' 導光體線狀溝之長邊方向成爲平行之方式來配置B - 7以外，進行相同於實施例5 -1之方式而製作面光源。亮燈10分鐘後，測定面光源面內之2 5點亮度（參照第18圖（a ))時，中心亮度爲41 10cd/m2、均勻度U爲81 %。另外’測定從面光源中央部之射出角分布後，視野角係縱向42°、橫向45°，得知雖然可以得到良好之均勻度u、視野角特性，但是中心亮度爲低的（參照表6 )。 (比較例5 - 5 ) -85- 200825468 除了使第1光學薄膜之異方向擴散性爲最大之方向與導光體線狀溝之長邊方向成爲垂直（亦即，Θ 5 = 90。）之方式來設置B-1以外，進行相同於實施例5-1之方式而製作面光源。亮燈10分鐘後，測定面光源面內之25點亮度（參照第18圖（a ))時，中心亮度爲36 80cd/m2、均勻度U爲78 %。另外，測定從面光源中央部之射出角分布後，視野角係縱向43°、橫向45°，得知雖然可以得到良好之均勻度U、 f " 視野角特性，但是中心亮度爲低的（參照表6 )。 (比較例5 - 6 ) 除了使第1光學薄膜之異方向擴散性爲最大之方向與導光體3之線狀溝之長邊方向成爲05=20°之方式來設置 B-1以外，進行相同於實施例5-1之方式而製作面光源。亮燈10分鐘後，測定面光源面內之25點亮度（參照弟18圖（a))時，中心亮度爲5170cd/m2、均句度U爲8〇 %。另外，測定從面光源中央部之射出角分布後，視野角係縱向40。、橫向40。，得知雖然可以得到良好之均勻度U、視野角特性，但是中心亮度爲低的（參照表6 )。 (比較例6 ) 除了將B - 6作爲第1光學薄膜使用以外，進行相同於實施例6之方式而製作面光源。亮燈10分鐘後，測定面光源面內之25點亮度（參照弟18圖（a))時，中心亮度爲5510cd/m2、均勻度U爲84 -86- 200825468 . %。另外，測定從面光源中央部之射出角分布後，視野角係縱向4 0。、橫向4 5。，得知雖然可以得到良好之均勻度U、視野角特性，但是中心亮度爲低的（參照表6 )。 (比較例7 ) 除了將B - 6作爲第1光學薄膜使用以外，進行相同於實施例7之方式而製作面光源。亮燈10分鐘後，測定面光源面內之2 5點亮度（參照弟18圖（a))時’中心売度爲2790cd/m2、均勻度U爲84 C、： %。另外，測定從面光源中央部之射出角分布後，視野角係縱向42°、橫向45°，得知雖然可以得到良好之均勻度U、視野角特性，但是中心亮度爲低的（參照表6 )。 (比較例8 ) 除了將B - 6作爲第1光學薄膜使用以外，進行相同於實施例8之方式而製作面光源。亮燈1 0分鐘後，測定面光源面內之9點亮度（參照第 [I 18圖（b))時’中心亮度爲4760cd/m2、均勻度U爲84%。另外’測定從面光源中央部之射出角分布後，視野角係縱向42°、橫向45°，彳辱知雖然可以得到良好之均勻度u、視野角特性，但是中心亮度爲低的（參照表7 )。 (比較例8 - 2〜8 - 6 ) 於實施例8-1之導光體上重疊相同於比較例8-2〜8-6 之薄膜後而製作面光源。將電源電壓3 .3 V供應至此面光源後而使LED亮燈。 -87- 200825468 亮燈1 0分鐘後，測定面光源面內之9點亮度（參照第 1 8圖（b ))、從面光源中央部之射出角分布時’得知雖然可以得到良好之均勻度U、視野角特性，但是中心亮度爲低的（參照表7 )。將以上實施例、比較例之結果顯示於表4〜7。於各表中，顯示使用之光源種類、使用之導光體種類、第1光學薄膜種類及線狀溝方向與第1光學薄膜之最大擴散方向的關係、第2光學薄膜種類、第1光學薄膜之最大擴散方向與第2光學薄膜之稜鏡長邊方向的關係、中心亮度、均勻度、視野角之評估。 -88- 200825468 【表4】（其1 ) 光源導光體第1光學薄膜種類導光體線狀溝方向與第1光學薄膜之最大擴散方向的關係實施例1-1 CCFL上下4燈 A-1 B-1 平行（θ5=0ο) 實施例1-2 CCFL上下4燈 A-1 B-2 平行（θ5 = 0ο) 實施例1-3 CCFL上下4燈 A-1 B-3 平行（<9 5 = 0。）實施例1-4 CCFL上下4燈 A-1 B-4 平行（Θ5=0〇) 實施例1-5 CCFL上下4燈 A-1 B-1 平行（Θ5 二0〇) 實施例1-6 CCFL上下4燈 A-1 B-1 平行（0 5=0°) 實施例1-7 CCFL上下4燈 A-1 B-1 平行（θ5 = 0ο) 實施例1-8 CCFL上下4燈 A-1 B-1 平行（Θ5 二 0°) 實施例1-9 CCFL上下4燈 A-1 B-1 05 = 5。實施例1-10 CCFL上下4燈 A-1 B-1 0 5 = 10° 比較例1-1 CCFL上下4燈 A-1 B-5 比較例1-2 CCFL上下4燈 A-1 B-6 比較例1-3 CCFL上下4燈 A-1 B-7 平行（Θ5二0〇) 比較例1-4 CCFL上下4燈 A-1 B-1 垂直（Θ 5 = 90°) 比較例1-5 CCFL上下4燈 A-1 B-2 垂直（Θ 5=90。）比較例1-6 CCFL上下4燈 A-1 B-3 垂直（0 5 = 90。）比較例1-7 CCFL上下4燈 A-1 B-1 Θ5 = 20° 實施例2 CCFL上下2燈 A-2 B-1 平行（Θ5 = 〇。）比較例2 CCFL上下2燈 A-2 B-5 實施例3 LED單側49燈 A-3 B-1 平行（θ5 = 0ο) 比較例3 LED單側49燈 A-3 B-5 -89- 200825468 【表4】（其2)After lighting for 10 minutes, when the brightness of the surface of the surface light source is measured at 25 points (矣M 18 (a)), the center brightness is 6740 cd/m2 (evaluation B), and the average degree U is 8 2 % (evaluation A) ), learned that the center brightness is superior, both _ p U. Further, after measuring the distribution of the exit angle from the central portion of the surface light source, the vertical angle of 3 1 ° (evaluation A) and the lateral direction of 45 ° (evaluation A) were observed, and the viewing angle characteristics of the good observation were obtained (see Table 4). (Example 1-6) C...i A surface light source was produced in the same manner as in Example 1-1 except that C-3 was used as the second optical film. After lighting for 10 minutes, the brightness of 25 points in the surface of the surface light source was measured (refer to Fig. 18(a)), the center brightness was 6720 cd/m2 (evaluation Β), and the self-degree U was 80% (evaluation A). I learned that there is a superior center brightness and a uniform degree U. Further, after measuring the distribution of the emission angle from the central portion of the surface light source, the viewing angle was 30 ° (evaluation A) and 4 4 ° (evaluation A) in the longitudinal direction, and the viewing angle characteristics showing good ΐ were obtained (see Table 4). (Example 1-7) A surface light source was produced in the same manner as in Example 1-1 except that C-4 was used as the second optical film. After lighting for 10 minutes, the brightness of 25 points in the surface of the surface light source was measured (refer to Fig. 18 (a)), the center brightness was 6505 cd/m2 (evaluation D), and the uniformity U was 80% (evaluation A). It is known that the center brightness and uniformity U are superior. Further, the distribution of the exit angle from the central portion of the surface light source was measured, and the viewing angle was -68-200825468. The longitudinal direction was 34 (evaluation A) and the lateral direction 46. (Evaluation A), it was found that the viewing angle characteristics were good (refer to Table 4). (Examples 1 - 8) C-1 was used as the second optical film, and the direction in which the diffusivity of the first optical film was maximized was perpendicular to the longitudinal direction of the prism of the second optical film (i.e., 06). A surface light source was produced in the same manner as in Example 1-1 except that the configuration was carried out in a manner of =90. After lighting for 10 minutes, the brightness at 25 points in the surface of the surface light source was measured (refer to ζ). Figure 18 (a)), the center brightness was 6500 cd/m2 (evaluation D), and the uniformity U was 75 % (evaluation A) , to know the superior center brightness, uniformity U. Further, after measuring the emission angle distribution from the central portion of the surface light source, the viewing angle was 48° in the longitudinal direction (evaluation A) and 30 in the lateral direction. (Evaluation A), it was found that the viewing angle characteristics were good (refer to Table 4). (Examples 1 to 9) In addition, the longitudinal direction of the linear groove which is the largest of the first optical film and the linear groove of the precursor 3 are set to 0 5 "= 5°. A surface light source was produced in the same manner as in Example 1-1 except for B-1. After lighting for 10 minutes, the brightness of 25 points in the surface of the surface light source was measured (refer to the figure 18 (a)), the center twist was 6780 cd/m 2 (evaluation B), and the uniformity U was 8 2 % (evaluation A ). It is known that the center brightness and uniformity U are superior. Further, after measuring the distribution of the exit angle from the central portion of the surface light source, the viewing angle was 3 2 ° (evaluation A) and 4 5 in the longitudinal direction. (Evaluation A), and it was found that the viewing angle characteristics of the good -69-200825468. (refer to Table 4). (Example 1 - 1 0) B is set in a force type in which the direction in which the diffusivity of the first optical film is maximized and the longitudinal direction of the linear groove of the light guide 3 becomes 0 5 = 1 〇 ° A surface light source was produced in the same manner as in Example 1-1 except for -1. After lighting for 10 minutes, the brightness at 25 points in the surface of the surface light source was measured (refer to Fig. 18(a)), the center luminance was 667 0 cd/m2 (evaluation C), and the uniform η degree U was 8 1 % (evaluation A). , to know the superior center brightness, uniformity U. Further, the distribution of the angle of incidence from the central portion of the surface light source was measured, and the viewing angle was longitudinally 3 3 . (Evaluation A), horizontal 44. (Evaluation A), it was found that the viewing angle characteristics were good (refer to Table 4). (Example 2) The light guide body A-1 is provided such that the surface on which the linear groove is not formed is the side of the observation side, and each of the two CCFLs is placed on the opposite two light incident I, and the surface is placed thereon. The surrounding "Lumirror" E6SV (made by Toray) is used as a reflector. A reflection sheet "Lumhror" E6SL (manufactured by Toray Co., Ltd.) is disposed on the non-observer side of the light guide 3. On the observer side of the light guide 3, the direction in which the diffusivity in the different direction of the first optical film is maximized is parallel to the longitudinal direction of the linear groove of the light guide 3 (that is, 05=0°). The way to set B-1. On the optical film Bi, the direction in which the long side direction of the second optical film and the diffusing direction of the optical film B-1 are maximized is parallel (that is, Θ 6 2 0 °) - 70- 200825468 To create a surface light source after setting C-1. Further, any of the first optical film and the second optical film is provided such that the uneven surface is on the observer side. The CCFL is turned on after the power supply voltage of 12V is supplied to the surface light source. After lighting for 10 minutes, the brightness of 25 points in the surface of the surface light source was measured (refer to Fig. 18 (a)), the center brightness was 7 3 5 0cd/m2 (evaluation A), and the uniformity U was 82% (evaluation A) ), we have a superior center brightness and uniformity U. Further, after measuring the distribution of the exit angle from the central portion of the surface light source, the viewing angle was 30° in the longitudinal direction (evaluation A) and 45° in the lateral direction (evaluation A), and the viewing angle characteristics of the display were observed (see Table 4). (Example 3) The light guide body A-3 is provided so that the surface on which the linear groove is not formed becomes the side of the observation side, and 49 light-emitting diodes (hereinafter referred to as LEDs) are arranged in parallel with the light incident surface. , "Lumirror" E6SV (made by Toray) is used as a reflector. A reflection sheet "Lumirror" E6SL (manufactured by Toray Co., Ltd.) is disposed on the non-observer side of the light guide 3. On the I observer side of the light guide 3, the direction in which the diffusivity in the different direction of the first optical film is maximized is parallel to the longitudinal direction of the linear groove of the light guide 3 (that is, 05=0°). ) to set B-1. On the optical film B-1, the direction in which the long side direction of the second optical film and the diffusing direction of the optical film B-1 are maximized is parallel (that is, 0 6 = 0 °). The way to set the C-1 is to create a surface light source. Further, any of the first optical film and the second optical film is provided such that the uneven surface is on the observer side. The supply voltage 15V is supplied to the surface light source to turn the LED on. -71 - 200825468 After the light is turned on for 10 minutes, the brightness at 25 points in the surface of the surface light source is measured (refer to Fig. 18(a)), the center brightness is 4320 cd/m2 (evaluation A), and the uniformity U is 8 2 % (evaluation) A), we have a superior center brightness and uniformity U. Further, after measuring the emission angle distribution from the central portion of the surface light source, the viewing angle was 30 ° (evaluation A) and 4 6 ° (evaluation A) in the longitudinal direction, and it was found that the viewing angle characteristics were good (see Table 4). (Example 4 - 1) The light-emitting body A-4 was placed so that the surface on which the linear groove was not formed, and the three LEDs were arranged in parallel with the light incident surface, and were disposed around the surface. Lumirror" E6SV (made by Toray) is used as a reflector. A reflection sheet "Lumirror" E6SL (manufactured by Toray Co., Ltd.) is disposed on the non-observer side of the light guide 3. On the observer side of the light guide 3, the direction in which the diffusivity in the different direction of the first optical film is maximized is parallel to the direction of the linear groove of the light guide 3 (that is, 0 5 = 0 °). The way to set B-1. On the optical film B-1, the direction in which the long side direction of the 光学I as the second optical film and the diffusivity in the opposite direction of the optical film B-1 are maximized (that is, 06=0°) The way to set C-1 to create a surface light source. Further, any of the first optical film and the second optical film is provided such that the uneven surface is on the observer side. The power supply voltage of 3.3 V is supplied to the surface light source to turn the LED on. After 10 minutes of lighting, the brightness of 9 points in the surface of the surface light source was measured (refer to Fig. 18(b)), the center brightness was 6470 cd/m2 (evaluation A), and the uniformity U was 8 2% (evaluation A). It is known that the center brightness and uniformity U are superior. -72- 200825468 . In addition, after measuring the distribution angle of the exit from the center of the surface light source, the viewing angle is 3 1 ° (evaluation a ) and 45 in the vertical direction. (Evaluation A), it was found that the viewing angle characteristics were good (refer to Table 5). (Example 4 - 2 to 4 - 10 ) A surface light source was produced by laminating the film of the same manner as in Examples 1-2 to 1-10 on the light guide of Example 4-1. The power supply voltage of 3. 3V is supplied to the surface light source to turn the LED on. After lighting for 1 minute, the brightness of 9 points in the surface of the surface light source was measured (refer to Fig. 18 (b)), and it was found that the center brightness and uniformity U were excellent. Further, when measuring the distribution of the exit angle from the central portion of the surface light source, it was found that good viewing angle characteristics were exhibited (see Table 5). (Example 5-1) The light guide body A-5 is provided so that the surface on which the linear groove is not formed becomes the side of the observation side, and each of the two CCFLs is disposed on the opposite two light incident surfaces. "Lumirror" E6SV (manufactured by Toray Co., Ltd.) (j is used as a reflector. Reflector is provided on the non-observer side of the light guide 3" Lumirror E6SL (made by Toray Co., Ltd.). On the observer side, B-1 is set such that the direction in which the diffusivity in the different direction of the first optical film is the largest and the direction of the linear groove of the light guide 3 are parallel (that is, 0 5 = 0°). In addition, B-6 is used as the second optical film to prepare a surface light source, and any of the first optical film and the second optical film is provided such that the uneven surface is on the observer side. The power supply voltage is supplied to the surface light source and the CCFL is turned on. -73- 200825468 After the light is turned on for 10 minutes, the brightness of the surface of the surface light source is measured at 25 o'clock (see Fig. 18(a)), and the center brightness is 5510 cd/ M2, uniformity 〇 is 82%, and it is known that it has superior central brightness and uniformity U. In addition, _ fixed from the surface light source After the distribution angle of the central portion is distributed, the viewing angle is 31.9 in the longitudinal direction and 4 1 in the lateral direction, and it is known that the viewing angle characteristics are good (refer to Table 6). (Example 5 - 2) Except that B-2 is used as the first optical A surface light source was produced in the same manner as in Example 5-1 except that the film was used. After the light was turned on for 10 minutes, the brightness at 25 points in the surface of the surface light source was measured (see Table 18), and the center twist was 5730 cd/m2. The uniformity U was 81%, and it was found that the center brightness and the uniformity U were excellent. Further, after measuring the distribution angle of the exit from the central portion of the surface light source, the viewing angle was 38 in the longitudinal direction and 40 in the lateral direction. Viewing angle characteristics (see Table 6) (Examples 5 - 3) A surface light source was produced in the same manner as in Example 5-1 except that B-3 was used as the first optical film. After 10 minutes of lighting, When measuring the brightness of 25 points in the surface of the surface light source (see Fig. 18(a)), the center luminance is 5440 cd/m2, and the uniformity u is 84%, and it is found that the center brightness and uniformity U are excellent. After the distribution angle of the central portion of the surface light source is distributed, the viewing angle is 3 9 in the longitudinal direction and 4 0 in the lateral direction. It was found that the viewing angle characteristics of the display were good (see Table 6). (Example 5-4) The same procedure as in the case of Example No. 4-1 was carried out except that B-4 was used as the first optical film. Surface light source. After 10 minutes of lighting, measure the brightness of 25 points in the surface of the surface light source (refer to Figure 18 (a)), the center brightness is 5300cd/m2, the uniformity U is %, and it is known that the center brightness is superior. Uniformity U. Further, after measuring the emission angle distribution from the central portion of the light source, the viewing angle is 40° in the longitudinal direction and the lateral direction 43 is good in viewing angle characteristics (see Table 6). (Example 5-5) Except that B-7 is the second A surface light source was produced in the same manner as in Example 5-1 except that the optical film was used. Further, the optical film Β-7 is set such that the direction in which the diffusivity in the different direction is maximized is set to be perpendicular to the direction in which the foreign diffusion of the optical film Β-1 is maximum (that is, 0 6 = 90°). . After lighting for 10 minutes, when measuring the brightness of 25 points in the surface of the surface light source (refer to Fig. 18 (a)), the center brightness is 5250 cd/m2, the uniformity U is %, and it is found that the center brightness and uniformity are superior. U. Further, after measuring the distribution of the exit angle from the center portion of the I) light plate, the viewing angle is 40 in the longitudinal direction. In the horizontal direction 42, the viewing angle characteristics of the display were observed (see Table 6). (Example 5-6) A surface light source was produced in the same manner as in Example 5-1 except that B-8 was used as the second optical film. After 10 minutes of lighting, measure the brightness of 25 points in the surface of the surface light source (see Figure 18 (a)). The center width is 5370cd/m2, and the uniformity U is %. It is known that the center brightness is superior. Uniformity U. In addition, the measurement is from the front side of the light source to the surface of the light source. The angle of view is 4 1 in the longitudinal direction. In the horizontal direction 4 3, it was found that the viewing angle characteristics were good (see Table 6). (Examples 5 - 7) A surface light source was produced in the same manner as in Example 5-1 except that B-9 was used as the second optical film. . After lighting for 10 minutes, when measuring the brightness of 25 points in the surface of the surface light source (refer to Fig. 18(a)), the center brightness is 5210 cd/m2, the uniformity U is Γ%, and it is found that the center brightness is uniform and uniform. Degree U. Further, after measuring the emission angle distribution from the central portion of the light source, the viewing angle is the longitudinal direction 42. In the horizontal direction 44, it is known that the viewing angle characteristics are good (see Table 6). (Examples 5 - 8) The length of the first optical film which is the maximum direction of the diffusivity in the opposite direction and the linear groove of the light guide 3 are made long. The side direction becomes 05=5. In the same manner as in Example 5-1 except that Β -1 was set, the surface source was produced. After 1 minute of lighting, measure the brightness of 25 points in the surface of the surface light source (refer to Figure 18 (a)), the center brightness is 5470cd/m2, the uniformity U is %, and it is known that the center brightness is uniform and uniform. Degree U. Further, after measuring the emission angle distribution from the central portion of the light source, the viewing angle is 40 in the longitudinal direction. In the horizontal direction 40, it is known that the viewing angle characteristics are good (refer to Table 6). (Example 5-9) The longitudinal direction of the linear groove which is the maximum direction of the diffusing property of the first optical film and the linear groove of the light guide 3 is 05 = 1 〇. The method is to illuminate the 82 sides in the direction of 83 sides. -76- 200825468 • The surface source is produced in the same manner as in the embodiment 5-1 except that B -1 is set. After 10 minutes of xenon lamp measurement, when measuring the brightness of 25 points in the surface of the surface light source (refer to Fig. 18(a)), the center brightness is 5350 cd/m2, and the uniformity U is %'. It is found that the center brightness and uniformity are superior. U. Further, after measuring the emission angle distribution from the central portion of the light source, the viewing angle is 40 in the longitudinal direction. In the horizontal direction 40, it is known that the viewing angle characteristics are good (refer to Table 6). (Example 6) f The light body A-6 is provided so that the surface on which the linear groove is not formed is the side of the observation side, and one CCFL is disposed on each of the opposite two light incident surfaces." Lumirror E6S V (Toray (share) system) is used as a reflector. A reverse film "Lumirror" E6SL (manufactured by Toray Co., Ltd.) is provided on the non-observer side of the light guide 3. On the observer side of the light guide 3, the direction in which the diffusivity in the different direction of the first optical film is the most is parallel to the longitudinal direction of the linear groove of the light guide 3 (that is, Θ5 = 0). To set B-1. On the optical film B-1, a surface light source was produced as a 光学-6 of the second optical film. Further, any of the first optical film and the second optical film is provided such that the uneven surface is on the observer side. The power supply voltage of 1 2 V is supplied to this surface light source and the CCFL lights up. After 10 minutes of lighting, the brightness of 25 points in the surface of the surface light source was measured (refer to Fig. 18(a)). The center brightness was 5970 cd/m2, and the uniformity U was %. It was found that the center brightness and uniformity U were superior. . In addition, after measuring the emission angle of the central portion of the light body from the surface of the light, the viewing angle is 3 9 in the longitudinal direction. In the lateral direction 4 1 , it is known that the viewing angle characteristics are good (refer to Table 6). (Example 7) The light body A-7 was placed so that the surface on which the linear groove was not formed was the side of the observation side, and 49 LEDs were arranged in parallel with the light incident surface, and "Lumirror" E6SV (Toray) was placed around it. (share) system as a reflector. A non-observer side is provided with a reflection sheet "Lumirror" E6SL (Toray). On the observer side of the light guide 3, the direction in which the first optical film r is diffused in the opposite direction and the light guide 3 are maximized. B-1 is provided so that the long side of the linear groove becomes parallel (that is, 05 = 0.). On the optical film B-1, B-6 as the second optical film is provided to form a surface source. Further, any of the first optical film and the second optical film is provided such that the concave surface is on the observer side, and the power supply voltage of 15 V is supplied to the surface light source to turn on the LED. After 10 minutes of lighting When measuring the brightness of 25 points in the surface of the surface light source (see Fig. 18(a)), the center brightness is 3450 cd/m2, the uniformity U is %, and it is known that the center brightness and uniformity U are superior. After measuring the distribution of the exit angle from the central portion of the light source, the viewing angle is 40 in the vertical direction, and the viewing angle characteristic in the horizontal direction 41 is good (see Table 6). (Example 8) The surface in which the linear groove is not formed is observed. Set the light body A-8 on the side of the side, and arrange three LEDs parallel to the light entrance surface, and place it around it. Mirroi·” E6SV (made by Toray (share)) as a reflector. The square light of the guide is set to -78-200825468, and the reflector is placed on the non-observer side of the light guide 3" Lunnrror" E6SL (Toray (share) system). The direction of the diffuser of the first optical film is maximized on the observer side of the light guide 3, and the longitudinal direction of the linear groove of the light guide 3 is parallel ( In other words, B-1 is provided in a manner of 0 5 = 0°. A surface light source is formed as B-6 of the second optical film on the optical film B-1. Further, the first optical film and the first optical film are provided. (2) The optical film is provided such that the uneven surface is on the observer side. The power supply voltage of 3.3 V is supplied to the surface light source to turn the LED on. f ^ Lights up for 10 minutes, and the surface light source is measured. At 9 o'clock brightness (see Fig. 18(b)), the center luminance is 5340 cd/m2, and the uniformity U is 82%, and it is found that the center luminance and the uniformity U are excellent. Further, the measurement is performed from the center of the surface light source. After the exit angle distribution, the viewing angle is 39° in the longitudinal direction and 41° in the lateral direction. The angular characteristics (refer to Table 7). (Examples 8-2 to 8-9) A surface light source was produced by laminating the film of the same manner as in Example 5·2 to 5 - 9 I on the light guide of Example 8.1. After supplying the power supply voltage of 3.3 V to the surface light source, the LED is turned on. After lighting for 10 minutes, the brightness of 9 points in the surface of the surface light source is measured (refer to Fig. 18 (b)), and the center is superior. Brightness, uniformity U. Further, after measuring the distribution of the emission angle from the central portion of the surface light source, it was found that any of the examples showed good viewing angle characteristics (see Table 7). (Comparative Example 1-1) A surface light source was produced in the same manner as in Example 1-1 except that B-5 was used as the first optical film. After the light was turned on for 10 minutes, the brightness at 25 points in the surface of the surface light source was measured (see Fig. 18(a)), the center luminance was 6210 cd/m2, and the uniformity U was 81%. Further, after measuring the distribution of the exit angle from the central portion of the surface light source, the viewing angle is 3 1 ° in the longitudinal direction and 45 ° in the lateral direction. It is found that although the uniform uniformity U and the viewing angle characteristics are obtained, the central luminance is low (refer to the table). 4). (Comparative Example 1-2) A surface light source was produced in the same manner as in Example 1-1 except that B-6 was used as the first optical film. After the light was turned on for 10 minutes, the brightness at 25 o'clock in the surface of the surface light source was measured (refer to Fig. 18 (a)), the center luminance was 6170 cd/m2 (evaluation E), and the uniformity U was 84% (evaluation A). Further, after measuring the distribution of the exit angle from the central portion of the surface light source, the viewing angle was 32° in the longitudinal direction (evaluation A) and 45 in the lateral direction. (Evaluation A), it was found that although a good uniformity U and viewing angle characteristics were obtained, the center twist was low (refer to Table 4). I (Comparative Example 1 - 3) A surface light source was produced in the same manner as in Example 1-1 except that B-7 was used as the first optical film. After the light was turned on for 10 minutes, the brightness at 25 o'clock in the surface of the surface light source was measured (refer to Fig. 18 (a)), the center luminance was 5 960 cd/m 2 (evaluation E ), and the uniformity U was 85 % (evaluation A). Further, after measuring the distribution of the exit angle from the central portion of the surface light source, the viewing angle is 3 1 in the longitudinal direction. (Evaluation A), horizontal 46. (Evaluation A), it was found that although good uniformity U and viewing angle characteristics were obtained, -80-200825468 • However, the central brightness was low (refer to Table 4) ° (Comparative Example 1-4) except that the first optical film was made. The direction in which the diffusivity in the different direction is the largest and the direction in which the long side of the linear groove of the light guide is perpendicular (that is, Θ 5 = 90) is set in the same manner as in Embodiment 1-1 except that B - 1 is set. The surface light source is produced in a manner. After lighting for 10 minutes, the brightness of 25 points in the surface of the surface light source was measured (refer to Fig. 18 (a)), the center brightness was 5 6 8 cd / m2 (evaluation e), uniform (one degree U was 84%) (Evaluation A.) Further, after measuring the emission angle distribution from the central portion of the surface light source, the viewing angle is 3 2 ° (evaluation A) and 4 7 (evaluation A) in the longitudinal direction. It is found that good uniformity U can be obtained. The viewing angle characteristic was low, but the center luminance was low (see Table 4). (Comparative Example 1 - 5) The direction in which the diffusivity of the first optical film in the opposite direction was maximized and the longitudinal direction of the linear groove of the light guide body It is vertical (that is, 0 5 = 90.) (the way to set B - 2 other than the same way as in the embodiment 1 _ 而 to create a surface light source. After lighting for 10 minutes 'measure the surface of the surface light source 2 When the brightness is 5 points (refer to Fig. 18(a)), the center brightness is 6〇30cd/m2 (evaluation E), and the uniformity U is 83% (evaluation A). In addition, the exit angle from the center of the surface light source is measured. After distribution, the viewing angle is longitudinally 3 1 (evaluation A) and lateral 4 6 (evaluation A )', although it is known that good uniformity u, field of view can be obtained. The angular characteristic, but the center twist is low (refer to Table 4). -81- 200825468 . (Comparative Example 1 - 6 ) The direction in which the diffusivity of the first optical film is maximized and the linear groove of the light guide The surface light source was produced in the same manner as in Example 1-1 except that the long side direction was vertical (that is, 0 5 2 90). The surface light source was measured after 10 minutes of lighting. In the case of the brightness of 2 points (see Fig. 18(a)), the center brightness is 5790 cd/m2 (evaluation E) and the uniformity U is 85% (evaluation a). In addition, the measurement from the center of the surface light source is measured. After the angular distribution, the viewing angle is 3 2 in the longitudinal direction (evaluation .A ) and 4 7 in the lateral direction (evaluation A ). It is known that although the uniformity u and the viewing angle are good, the central shell is low. (Comparative Example 1 - 7) The direction in which the direction in which the first optical film is diffused in the opposite direction is the largest and the direction in which the linear groove of the light guide 3 is in the longitudinal direction is 0 5 = 20. A surface light source was produced in the same manner as in Example 1-1 except that B -1 was set. [; After 1 minute, the surface light source was measured. In the case of the brightness of 2 points (see Fig. 18(a)), the center brightness is 6490 cd/m2 (evaluation E), and the uniformity U is 80% (evaluation A). In addition, the measurement is taken from the center of the surface light source. After the angular distribution, the viewing angle is 3 5 (evaluation A) and 4 2 in the transverse direction (evaluation A), and it is found that although good uniformity U and viewing angle characteristics can be obtained, the central luminance is low. (Comparative Example 2) A surface light source was produced in the same manner as in Example 2 except that B-5 was used as the second optical film. After the light was turned on for 10 minutes, the brightness at 25 points in the surface of the surface light source was measured (see Fig. 18(a)), the center luminance was 6710 cd/m2 (evaluation E), and the uniformity U was 84% (evaluation A). Further, after measuring the distribution of the exit angle from the central portion of the surface light source, the viewing angle is 3 1 in the longitudinal direction. (Evaluation A), horizontal 4 6 . (Evaluation A)' It was found that although the uniformity u and the viewing angle characteristics were good, the center luminance was low (refer to Table 4). (Comparative Example 3) (' A surface light source was produced in the same manner as in Example 3 except that B-5 was used as the second optical film. After lighting for 10 minutes, the brightness of the surface of the surface light source was measured at 25 points ( Referring to Fig. 18(b)), the center luminance is 3 790 cd/m2 (evaluation E), and the uniformity U is 8.4% (evaluation A). In addition, the field of view is measured from the central portion of the surface light source. The longitudinal direction of the horn is 3 1 (evaluation A ) and the lateral direction 4 6 (evaluation A ), and it is known that although good uniformity u and viewing angle characteristics can be obtained, ^ the central brightness is low (refer to Table 4). Example 4-1) A surface light source was produced in the same manner as in Example 4 except that B-5 was used as the first optical film. After lighting for 1 minute, the measurement was performed at 9 points in the surface of the surface light source (see the In Fig. 18(b)), the center luminance is 5760 cd/m2 (evaluation E) and the uniformity U is 84% (evaluation A). In addition, the measurement of the exit angle distribution from the central portion of the surface light source is performed. (Evaluation A), horizontal 4 5 (evaluation -83-200825468 • A), knowing that although good uniformity can be obtained, The viewing angle characteristic was low, but the center luminance was low (refer to Table 5). (Comparative Example 4 - 2 to 4 - 7 ) The film similar to Comparative Example 1_2 to 1-7 was superposed on the light guiding body of Example 4-1. The surface light source is produced. The power supply voltage is supplied to the surface light source after 3.3 V, and the LED is turned on. After lighting for 10 minutes, the brightness of the surface of the surface light source is measured at 9 o'clock (refer to Fig. 18 (b)). When the emission angle distribution of the central portion of the light source is distributed, it is found that a good uniformity U and a viewing angle characteristic are obtained, but the central luminance is low (see Table 5). (Comparative Example 5 -1) Except for B-6 A surface light source was produced in the same manner as in Example 5-1 except that the optical film was used. After the light was turned on for 10 minutes, the brightness of the surface of the surface light source was measured at 25 o'clock (see Fig. 18 (a)). The degree is 5150 cd/m2, and the uniformity U is 85 I, %. Further, after measuring the emission angle distribution from the central portion of the surface light source, the viewing angle is 40 in the longitudinal direction and 45 in the lateral direction. It is found that a good uniformity U can be obtained. , viewing angle characteristics, but the center brightness is low (refer to Table 6). (Comparative Example 5 - 2) In addition to B - 8 A surface light source was produced in the same manner as in Example 5-1 except that B-1 was used as the second optical film, and the brightness of the surface light source was measured at 10 o'clock. (Refer to -84-200825468. In Fig. 18(a)), the center luminance is 4100 cd/m2, and the uniformity U is 84%. Further, after measuring the emission angle distribution from the central portion of the surface light source, the viewing angle is longitudinally 4 1 . Horizontal 45. It was found that although good uniformity U and viewing angle characteristics were obtained, the center luminance was low (refer to Table 6). (Comparative Example 5 - 3) An f-surface light source was produced in the same manner as in Example 5-1 except that B-9 was used as the first optical film and B-9 was used as the second optical film. After the light was turned on for 10 minutes, the brightness of 25 points in the surface of the surface light source was measured (see Fig. 18(a)), the center luminance was 435 cd/m2, and the uniformity U was 84%. Further, after measuring the emission angle distribution from the central portion of the surface light source, the viewing angle is the longitudinal direction 42. 45° in the lateral direction, it was found that although good uniformity u and viewing angle characteristics were obtained, the central luminance was low (see Table 6). (Comparative Example 5-4) The same procedure as in the example except that the direction in which the diffusivity of the first optical film is maximized is set to be parallel to the direction in which the longitudinal direction of the linear groove of the light guide is parallel A surface light source is produced in a 5 -1 manner. After the light was turned on for 10 minutes, the brightness of 25 points in the surface of the surface light source was measured (see Fig. 18(a)), the center luminance was 41 10 cd/m2, and the uniformity U was 81%. In addition, after measuring the distribution of the exit angle from the central portion of the surface light source, the viewing angle is 42° in the longitudinal direction and 45° in the lateral direction. It is found that although the uniformity u and the viewing angle are good, the central luminance is low (refer to Table 6). ). (Comparative Example 5 - 5) -85- 200825468 The direction in which the diffusivity of the first optical film in the different direction is maximized is perpendicular to the longitudinal direction of the linear groove of the light guide (that is, Θ 5 = 90). In the same manner as in the case of setting B-1, a surface light source was produced in the same manner as in Example 5-1. After lighting for 10 minutes, the brightness at 25 points in the surface of the surface light source was measured (see Fig. 18(a)), the center luminance was 36 80 cd/m2, and the uniformity U was 78%. Further, after measuring the distribution of the exit angle from the central portion of the surface light source, the viewing angle was 43° in the longitudinal direction and 45° in the lateral direction, and it was found that although the uniform uniformity U, f " viewing angle characteristics were obtained, the central luminance was low ( Refer to Table 6). (Comparative Example 5 - 6) Except that B-1 is provided so that the direction in which the first direction of the first optical film is diffused in the opposite direction and the direction in which the longitudinal direction of the linear groove of the light guide 3 is 05 = 20° A surface light source was produced in the same manner as in Example 5-1. After lighting for 10 minutes, the brightness of 25 points in the surface of the surface light source was measured (refer to Fig. 18 (a)), the center luminance was 5170 cd/m2, and the uniformity U was 8 〇 %. Further, after measuring the emission angle distribution from the central portion of the surface light source, the viewing angle is 40 in the longitudinal direction. Horizontal 40. It was found that although good uniformity U and viewing angle characteristics were obtained, the center luminance was low (refer to Table 6). (Comparative Example 6) A surface light source was produced in the same manner as in Example 6 except that B-6 was used as the first optical film. After lighting for 10 minutes, the brightness at 25 points in the surface of the surface light source was measured (refer to Figure 18 (a)), the center luminance was 5510 cd/m2, and the uniformity U was 84 -86-200825468.%. Further, after measuring the emission angle distribution from the central portion of the surface light source, the viewing angle is 40 in the longitudinal direction. Horizontal 4 5 . It was found that although good uniformity U and viewing angle characteristics were obtained, the center luminance was low (refer to Table 6). (Comparative Example 7) A surface light source was produced in the same manner as in Example 7 except that B-6 was used as the first optical film. After the light was turned on for 10 minutes, the brightness of 25 points in the surface of the surface light source was measured (see Fig. 18 (a)). The center twist was 2790 cd/m2, and the uniformity U was 84 C, %. Further, after measuring the emission angle distribution from the central portion of the surface light source, the viewing angle was 42° in the longitudinal direction and 45° in the lateral direction, and it was found that although the uniform uniformity U and the viewing angle characteristics were obtained, the central luminance was low (refer to Table 6). ). (Comparative Example 8) A surface light source was produced in the same manner as in Example 8 except that B-6 was used as the first optical film. After 10 minutes of lighting, the brightness at 9 o'clock in the surface of the surface light source was measured (see [N 18 (b)), the center luminance was 4760 cd/m2, and the uniformity U was 84%. In addition, after measuring the distribution of the exit angle from the central portion of the surface light source, the viewing angle is 42° in the longitudinal direction and 45° in the lateral direction. Although it is possible to obtain good uniformity u and viewing angle characteristics, the central brightness is low (see Table). 7). (Comparative Example 8 - 2 to 8 - 6 ) A film similar to that of Comparative Examples 8-2 to 8-6 was superposed on the light guide of Example 8-1 to prepare a surface light source. The power supply voltage of 3.3 μV is supplied to the surface light source to turn the LED on. -87- 200825468 After 10 minutes of lighting, the brightness of 9 points in the surface of the surface light source is measured (refer to Fig. 18 (b)), and the distribution of the exit angle from the central portion of the surface light source is known to be good even though Degree U, viewing angle characteristics, but the center brightness is low (refer to Table 7). The results of the above examples and comparative examples are shown in Tables 4 to 7. In each of the tables, the type of the light source to be used, the type of the light guide to be used, the type of the first optical film, the relationship between the direction of the linear groove and the maximum diffusion direction of the first optical film, the type of the second optical film, and the first optical film are shown. The relationship between the maximum diffusion direction and the longitudinal direction of the second optical film, and the evaluation of the center luminance, uniformity, and viewing angle. -88-200825468 [Table 4] (1) The relationship between the direction of the linear light guide of the light guide body of the first optical film type and the maximum diffusion direction of the first optical film. Example 1-1 CCFL up and down 4 lamps A- 1 B-1 Parallel (θ5=0ο) Example 1-2 CCFL up and down 4 lamps A-1 B-2 Parallel (θ5 = 0ο) Example 1-3 CCFL up and down 4 lamps A-1 B-3 parallel (< 9 5 = 0.) Example 1-4 CCFL up and down 4 lights A-1 B-4 parallel (Θ5=0〇) Example 1-5 CCFL up and down 4 lights A-1 B-1 parallel (Θ5 2 0〇) Example 1-6 CCFL up and down 4 lamps A-1 B-1 parallel (0 5=0°) Example 1-7 CCFL up and down 4 lamps A-1 B-1 parallel (θ5 = 0ο) Example 1-8 CCFL Up and down 4 lights A-1 B-1 are parallel (Θ5 2 0°) Example 1-9 CCFL up and down 4 lights A-1 B-1 05 = 5. Example 1-10 CCFL up and down 4 lamps A-1 B-1 0 5 = 10° Comparative Example 1-1 CCFL up and down 4 lamps A-1 B-5 Comparative example 1-2 CCFL up and down 4 lamps A-1 B-6 Comparative Example 1-3 CCFL up and down 4 lamps A-1 B-7 parallel (Θ5 2 0〇) Comparative Example 1-4 CCFL up and down 4 lamps A-1 B-1 Vertical (Θ 5 = 90°) Comparative Example 1-5 CCFL up and down 4 lights A-1 B-2 vertical (Θ 5=90.) Comparative example 1-6 CCFL up and down 4 lights A-1 B-3 vertical (0 5 = 90.) Comparative example 1-7 CCFL up and down 4 lights A-1 B-1 Θ5 = 20° Example 2 CCFL up and down 2 lamps A-2 B-1 parallel (Θ5 = 〇.) Comparative example 2 CCFL up and down 2 lamps A-2 B-5 Example 3 LED single side 49 Lamp A-3 B-1 is parallel (θ5 = 0ο) Comparative Example 3 LED single side 49 lamp A-3 B-5 -89- 200825468 [Table 4] (2)

第2光學薄膜中心亮度均勻度視野角（°) 種類第1光學薄膜之最大擴散方向與第2光學薄膜之稜鏡長邊方向的關係畫面縱向畫面橫向實施例1-1 C-1 平行（Θ 6=0。） A A A A 實施例1-2 C-1 平行（Θ 6=0。） A A A A 實施例1-3 C-1 平行（Θ6二 0°) C A A A 實施例1-4 C-1 平行（Θ 6=0。） D A A A 實施例1-5 C-2 平行（θ6=0ο) B A A A 實施例1-6 C-3 平行（0 6=0。） B A A A 實施例1-7 C-4 平行（Θ6=0°) D A A A 實施例1-8 C-1 垂直⑽ D B A A 實施例1-9 C-1 平行（Θ 6=0。） B A A A 實施例1-10 C-1 平行（Θ 6=0。） C A A A 比較例1-1 C-1 平行（Θ 6=0。） E A A A 比較例1-2 C-1 平行（Θ6二0。） E A A A 比較例1-3 C-1 平行（Θ 6=0。） E A A A 比較例1-4 C-1 平行（Θ 6 = 0。） E A A A 比較例1-5 C-1 平行（Θ 6=0。） E A A A 比較例1-6 C-1 平行（Θ6=0°) E A A A 比較例1-7 C-1 平行（Θ 6=0。） E A A A 實施例2 C-1 平行（θ6=0ο) A A A A 比較例2 C-1 平行（Θ6 二0〇) E A A A 實施例3 C-1 平行（Θ 6=0。） A A A A 比較例3 C-1 平行（Θ6二0〇) E A A A -90- 200825468 ；由表4得知：使用1 7吋之導光體a -1，將棱鏡片作爲第2光學薄膜使用的本發明構造之實施例1 _丨〜丨_ 1 〇中任一例均爲良好之中心亮度、具優越之均勻度、視野角特性。另外，使用異方向擴散性小的異方向擴散片 b_7 (D m aX/D mi η = 1 · 6 )之比較例1 - 3也可以得到良好之均勻度U、視野角特性，但是中心亮度爲低的。另外，得知：雖然使用等方向擴散性片Β - 5、Β - 6之比較例1 -1、；[«_ 2、2、 f 3可以得到良好之均勻度U、視野角特性，但是中心亮度爲 i 低的。另外，得知：即使使用異方向擴散片，導光體線狀溝方向與第1光學薄膜最大擴散方向的關係爲垂直之比較例1 - 4、1- 5、1 - 6及非平行之比較例1 - 7也可以得到良好之均勻度U、視野角特性，但是中心亮度爲低的。 -91- 200825468 【表5】（其1 ) 光源導光體第1光學薄膜種類導光體線狀溝方向與第1光學薄膜之最大擴散方向的關係實施例4_1 LED單側3燈 A-4 B-1 平行（0 5=0。）實施例4-2 娜單側3燈 A-4 B-2 平行（Θ 5=0。）實施例4-3 LED單側3燈 A4 B-3 平行（Θ 5=0。）實施例4-4 LED單側3燈 A-4 B-4 平行（Θ 5 = 0。）實施例4-5 LED單側3燈 A4 B-1 平行（θ5=0ο) 實施例4-6 LED單側3燈 A-4 B-1 平行（Θ5 = 0。）實施例4·7 哪單側3燈 A-4 B-1 平行（0 5=0。）實施例4-8 LHD單側3燈 A-4 B-1 平行（Θ 5=0。）實施例4-9 LED單側3燈 A-4 B-1 Θ5 = 5。實施例4-10 LED單側3燈 A-4 B-1 Θ5二 10° 比較例4-1 LK)單側3燈 A-4 B-5 比較例4-2 LED單側3燈 A-4 B-6 比較例4-3 LED單側3燈 A-4 B-7 平行（Θ 5=0。）比較例4-4 LED單側3燈 A4 B-1 垂直（Θ 5 = 90。）比較例4-5 LED單側3燈 A-4 B-2 垂直（05 = 90。）比較例4-6 LED單側3燈 A-4 B-3 垂直（Θ 5=90。）比較例4-7 LED單側3燈 A-4 B-1 (9 5=20。 - 92- 200825468 【表5】（其2)Second optical film center brightness uniformity viewing angle (°) Relationship between the maximum diffusion direction of the first optical film and the longitudinal direction of the second optical film Screen vertical screen Horizontal embodiment 1-1 C-1 Parallel (Θ 6 = 0.) AAAA Example 1-2 C-1 Parallel (Θ 6 = 0.) AAAA Example 1-3 C-1 Parallel (Θ6 2 0°) CAAA Example 1-4 C-1 Parallel (Θ 6 = 0.) DAAA Example 1-5 C-2 Parallel (θ6=0ο) BAAA Example 1-6 C-3 Parallel (0 6=0.) BAAA Example 1-7 C-4 Parallel (Θ6= 0°) DAAA Example 1-8 C-1 Vertical (10) DBAA Example 1-9 C-1 Parallel (Θ 6=0.) BAAA Example 1-10 C-1 Parallel (Θ 6=0.) CAAA Comparison Example 1-1 C-1 Parallel (Θ 6 = 0.) EAAA Comparative Example 1-2 C-1 Parallel (Θ6 2 0.) EAAA Comparative Example 1-3 C-1 Parallel (Θ 6=0.) EAAA Comparison Example 1-4 C-1 Parallel (Θ 6 = 0.) EAAA Comparative Example 1-5 C-1 Parallel (Θ 6=0.) EAAA Comparative Example 1-6 C-1 Parallel (Θ6=0°) EAAA Comparison Example 1-7 C-1 Parallel (Θ 6=0.) EAAA Example 2 C-1 Parallel (θ6 =0ο) AAAA Comparative Example 2 C-1 Parallel (Θ6 〇2〇) EAAA Example 3 C-1 Parallel (Θ 6=0.) AAAA Comparative Example 3 C-1 Parallel (Θ6二0〇) EAAA -90- 200825468; It is known from Table 4 that any of the examples 1 to _丨~丨_ 1 of the structure of the present invention using the prism sheet as the second optical film using the light guide a -1 of 1 7 均为 is good. The center brightness, superior uniformity, and viewing angle characteristics. Further, in Comparative Example 1-3 using the different-direction diffusing sheet b_7 (D m aX/D mi η = 1 · 6 ) having a small difference in the divergence, a good uniformity U and a viewing angle characteristic were obtained, but the central luminance was low. In addition, it is known that although the isotropic diffusing sheet Β-5, Β-6 of Comparative Example 1-1, [«_ 2, 2, f 3 can obtain good uniformity U, viewing angle characteristics, but the center The brightness is i low. Further, it was found that even when the opposite-direction diffusion sheet was used, the relationship between the direction of the linear groove of the light guide and the maximum diffusion direction of the first optical film was vertical, and the comparison of Comparative Examples 1-4, 1-5, 1-6, and non-parallel Examples 1 - 7 also gave good uniformity U and viewing angle characteristics, but the center brightness was low. -91-200825468 [Table 5] (1) Light source light guide First optical film type Relationship between light guide linear groove direction and maximum diffusion direction of first optical film Example 4_1 LED single side 3 lamp A-4 B-1 parallel (0 5 = 0.) Example 4-2 Na unilateral 3 lamps A-4 B-2 parallel (Θ 5 = 0.) Example 4-3 LED single side 3 lamps A4 B-3 parallel (Θ 5 = 0.) Example 4-4 LED single-sided 3 lamps A-4 B-4 parallel (Θ 5 = 0.) Example 4-5 LED single-sided 3 lamps A4 B-1 parallel (θ5=0ο Example 4-6 LED Single Side 3 Lamp A-4 B-1 Parallel (Θ5 = 0.) Example 4·7 Which One Side 3 Lamp A-4 B-1 Parallel (0 5=0.) Example 4-8 LHD Single Side 3 Lamp A-4 B-1 Parallel (Θ 5=0.) Example 4-9 LED One Side 3 Lamp A-4 B-1 Θ5 = 5. Example 4-10 LED Single Side 3 Lamp A-4 B-1 Θ5 2 10° Comparative Example 4-1 LK) One Side 3 Lamp A-4 B-5 Comparative Example 4-2 LED One Side 3 Lamp A-4 B-6 Comparative Example 4-3 LED Single Side 3 Lamp A-4 B-7 Parallel (Θ 5=0.) Comparative Example 4-4 LED One Side 3 Lamp A4 B-1 Vertical (Θ 5 = 90.) Example 4-5 LED Single Side 3 Lamp A-4 B-2 Vertical (05 = 90.) Comparative Example 4-6 LED Single Side 3 Lamp A-4 B-3 Vertical (Θ 5=90.) Comparative Example 4 7 LED single side 3 lamp A-4 B-1 (9 5=20. - 92- 200825468 [Table 5] (2)

第2光學薄膜中心亮度均勻度視野角（〇) 種類第1光學薄膜之最大擴散方向與第2 光學薄膜之稜鏡長邊方向的關係畫面縱向畫面橫向實施例4-1 C-1 平行（Θ 6=0。） A A A A 實施例4-2 C-1 平行（Θ 6=0。） A A A A 實施例4-3 C-1 平行（θ6=0ο) C A A A 實施例4-4 C-1 平行（<9 6=0。） D A A A 實施例4-5 C-2 平行（0 6=0。） B A A A 實施例4-6 C-3 平行（/96=0。） B A A A 實施例4-7 C-4 平行（0 6=0。） D A A A 實施例4-8 C-1 垂直（Θ6=%。） D B A A 實施例4-9 C-1 平行（θ6=0ο) B A A A 實施例4-10 C-1 平行（0 6=0。） C A A A 比較例4-1 C-1 平行（(96=0。） E A A A 比較例4-2 C-1 平行（0 6=0。） E A A A 比較例4-3 C-1 平行（(9 6=0。） E A A A 比較例4·4 C-1 平行（6>6=0〇) E A A A 比較例4-5 C-1 平行（0 6=0。） E A A A 比較例4-6 C-1 平行（06=0。） E A A A 比較例4-7 C-1 平行（(96=〇。） 1 E A A A 由表5得知：即使使用小尺寸之導光體a_4，將稜鏡片作爲第2光學薄膜使用之情形，本發明構造之實施例4 _丄〜4-1 0、實施例2、3中任一例均爲良好之中心亮度、具優越之均勻度、’視野角特性。尤其，得知：即使第丄光學薄 -93- 200825468 ；膜之最大擴散方向與第2光學薄膜之稜鏡長邊方向的關係處於直角’雖然若干中心亮度惡化（評估D )，但是仍能禁得起使用。另外，得知：雖然使用等方向擴散性片B-5、 B-6之比較例4-1、4-2可以得到良好之均勻度U、視野角特性’但是中心亮度爲低的。另外，使用異方向擴散性小的異方向擴散片B-7 ( Dmax/Dmin= 1.6 )之比較例4-3也可以得到良好之均勻度U、視野角特性，但是中心亮度爲低 $ 的。另外’得知：即使使用異方向擴散片，導光體線狀溝方向與第1光學薄膜最大擴散方向的關係爲垂直之比較例 4-4、4-5、4-6及非平行之比較例4-7也可以得到良好之均句度U、視野角特性，但是中心亮度爲低的。 -94- 200825468 【表6】（其1 ) 光源導光體第1光學薄膜種類導光體線狀溝方向與第1光學薄膜之最大擴散方向的關係實施例5-1 CCFL上下4燈 A-5 B-1 平行（Θ5 二 0〇) 實施例5-2 CCFL上下4燈 A-5 B-2 平行（θ5=0ο) 實施例5-3 CCFL上下4燈 A-5 B-3 平行（Θ5 二 0。）實施例54 CCFL上下4燈 A-5 B-4 平行（(9 5 = 0。）實施例55 CCFL上下4燈 A-5 B-1 平行（Θ5 = 0。）實施例5-6 CCFL上下4燈 A-5 B-1 平行（Θ 5 = 0。）實施例5-7 CCFL上下4燈 A-5 B-1 平行（Θ5 二0。）實施例5-8 CCFL上下4燈 A-5 B-1 05 = 5。實施例5-9 CCFL上下4燈 A-5 B-1 θ5 = 10ο 比較例5-1 CCFL上下4燈 A-5 B-6 比較例5-2 CCFL上下4燈 A-5 B-8 比較例5-3 CCFL上下4燈 A-5 B-9 比較例5-4 CCFL上下4燈 A-5 B-7 平行（θ5 = 0ο) 比較例5-5 CCFL上下4燈 A-5 B-1 垂直（0 5 = 90。）比較例5-6 CCFL上下4燈 A-5 B-1 6>5-20〇實施例6 CCFL上下2燈 A-6 B-1 平行（Θ 5=0。）比較例6 CCFL上下2燈 A-6 B-6 實施例7 LED單側49燈 A-7 B-1 平行（0 5二〇〇) 比較例7 LED單側49燈 A-7 B-6 -95- 200825468 【表6】（其2)Second optical film center brightness uniformity viewing angle (〇) The relationship between the maximum diffusion direction of the first optical film and the longitudinal direction of the second optical film. The vertical picture of the picture is horizontal. Example 4-1 C-1 Parallel (Θ 6 = 0.) AAAA Example 4-2 C-1 Parallel (Θ 6 = 0.) AAAA Example 4-3 C-1 Parallel (θ6=0ο) CAAA Example 4-4 C-1 Parallel (<> 9 6 = 0.) DAAA Example 4-5 C-2 Parallel (0 6 = 0.) BAAA Example 4-6 C-3 Parallel (/96 = 0.) BAAA Example 4-7 C-4 Parallel (0 6 = 0.) DAAA Example 4-8 C-1 Vertical (Θ6=%.) DBAA Example 4-9 C-1 Parallel (θ6=0ο) BAAA Example 4-10 C-1 Parallel (0 6 = 0.) CAAA Comparative Example 4-1 C-1 Parallel ((96 = 0) EAAA Comparative Example 4-2 C-1 Parallel (0 6 = 0.) EAAA Comparative Example 4-3 C-1 Parallel ( (9 6 = 0.) EAAA Comparative Example 4·4 C-1 Parallel (6 > 6 = 0 〇) EAAA Comparative Example 4-5 C-1 Parallel (0 6 = 0.) EAAA Comparative Example 4-6 C- 1 Parallel (06=0.) EAAA Comparative Example 4-7 C-1 Parallel ((96=〇.) 1 EAAA Even when a small-sized light guide body a_4 is used and a ruthenium sheet is used as the second optical film, any one of the embodiments of the present invention is _丄~4-1 0, and the examples 2 and 3 are good centers. Brightness, superior uniformity, and 'viewing angle characteristics. In particular, it is known that even the second optical thin film-93-200825468; the relationship between the maximum diffusion direction of the film and the long-side direction of the second optical film is at right angles' Some of the center brightness deteriorated (Evaluation D), but it was still able to withstand use. In addition, it was found that although Comparative Examples 4-1 and 4-2 using the isotropic diffusible sheets B-5 and B-6, good uniformity was obtained. U, viewing angle characteristic 'but the center brightness is low. Further, a good uniformity U can be obtained by using the comparative example 4-3 of the different direction diffusing sheet B-7 having a different diffusivity in the opposite direction (Dmax/Dmin = 1.6). And the viewing angle characteristic, but the center luminance is lower than $. In addition, it is known that the relationship between the direction of the linear groove of the light guide and the maximum diffusion direction of the first optical film is perpendicular even when the opposite-direction diffusion sheet is used. 4-5, 4-6 and non-parallel comparison examples 4-7 Sentence can be of U, the viewing angle characteristics are excellent, but the central brightness was low. -94-200825468 [Table 6] (1) The relationship between the direction of the linear light guide of the light guide body of the first optical film type and the maximum diffusion direction of the first optical film. Example 5-1 CCFL up and down 4 lamps A- 5 B-1 Parallel (Θ5 2〇) Example 5-2 CCFL up and down 4 lamps A-5 B-2 Parallel (θ5=0ο) Example 5-3 CCFL up and down 4 lamps A-5 B-3 Parallel (Θ5 20)) Example 54 CCFL up and down 4 lamps A-5 B-4 parallel ((9 5 = 0.) Example 55 CCFL up and down 4 lamps A-5 B-1 parallel (Θ5 = 0.) Example 5 - 6 CCFL up and down 4 lights A-5 B-1 parallel (Θ 5 = 0.) Example 5-7 CCFL up and down 4 lights A-5 B-1 parallel (Θ5 2 0.) Example 5-8 CCFL up and down 4 lights A-5 B-1 05 = 5. Example 5-9 CCFL up and down 4 lamps A-5 B-1 θ5 = 10ο Comparative Example 5-1 CCFL up and down 4 lamps A-5 B-6 Comparative example 5-2 CCFL up and down 4 Lamp A-5 B-8 Comparative Example 5-3 CCFL Up and Down 4 Lamps A-5 B-9 Comparative Example 5-4 CCFL Up and Down 4 Lamps A-5 B-7 Parallel (θ5 = 0ο) Comparative Example 5-5 CCFL Up and down 4 lights A-5 B-1 vertical (0 5 = 90.) Comparative example 5-6 CCFL up and down 4 lights A-5 B-1 6> 5-20 〇 Example 6 CCFL up and down 2 lights A-6 B- 1 Parallel (Θ 5=0. Comparative Example 6 CCFL up and down 2 lamps A-6 B-6 Example 7 LED single side 49 lamps A-7 B-1 Parallel (0 5 2) Comparative example 7 LED single side 49 lamps A-7 B-6 -95- 200825468 [Table 6] (2)

第2光學薄膜中心亮度均勻度視野角（°) 種類第1光學薄膜之最大擴散方向與第2 光學薄膜之最大擴散方向的關係畫面縱向畫面橫向實施例5-1 B-6 A A A A 實施例5-2 B-6 A A A A 實施例5-3 B-6 B A A A 實施例5-4 B-6 C A A A 實施例5-5 B-7 垂直（Θ 6 二 90°) D A A A 實施例5-6 B-8 C A A A 實施例5-7 B-9 D A A A 實施例5-8 B-6 B A A A 實施例5-9 B-6 C A A A 比較例5-1 B-6 E A A A 比較例5-2 B-8 E A A A 比較例5-3 B-9 E A A A 比較例5-4 B-6 E A A A 比較例5-5 B-6 E B A A 比較例5-6 B-6 D A A A 實施例6 B-6 A A A A 比較例6 B-6 E A A A 實施例7 B-6 A A A A 比較例7 B-6 E A A A -96- 200825468 由表6得知：即使將擴散片作爲第2光學薄膜使用之情形，本發明構造之實施例5 -1〜5 -9、實施例6、7中任一例均爲良好之中心亮度、具優越之均勻度、視野角特性。另外得知：雖然使用等方向擴散性片B-6、B-8、B_9之比較例5 -1、5 · 2、5 - 3、比較例6、7可以得到良好之均勻度U、視野角特性，但是中心亮度爲低的。另外，使用異方向擴散性小的異方向擴散片 B-7(Dmax/Dmin=1.6)之比較例 5 -4也可以得到良好之均勻度u、視野角特性，但是中心亮度爲低的。另外，得知：即使使用異方向擴散片，導光體線狀溝方向與第1光學薄膜最大擴散方向的關係爲垂直之比較例5-5及非平行之比較例5-6也可以得到良好之均勻度 U、視野角特性，但是中心亮度爲低的。 -97- 200825468 【表7】（其1 ) 光源導光體第1光學薄膜種類導光體線狀溝方向與第1光學薄膜之最大擴散方向的關係實施例8-1 LED單側3燈 A-8 B-1 平行（θ5=0ο) 實施例8-2 LED單側3燈 A-8 B-2 平行（0 5 = 0°) 實施例8-3 LED單側3燈 A-8 B-3 平行（Θ 5 = 0。）實施例8-4 LED單側3燈 A-8 B4 平行（θ5 = 0ο) 實施例8-5 LED單側3燈 A-8 B-1 平行（Θ 5 = 0。）實施例8-6 LED單側3燈 A-8 B-1 平行（Θ 5 = 0。）實施例8-7 LED單側3燈 A-8 B-1 平行（θ5=0ο) 實施例8-8 LED單側3燈 A-8 B-1 05 = 5。實施例8-9 LED單側3燈 A-8 B-1 0 5 = 10。比較例8-1 LED單側3燈 A-8 B-6 比較例8-2 UED單側3燈 A-8 B-8 比較例8-3 LED單側3燈 A-8 B-9 比較例8-4 LED單側3燈 A-8 B-7 平行（Θ5 = 〇。）比較例8_5 led單俱丨m登 A-8 B-1 垂直（(9 5 = 90°) 比較例8-6 LED單側3燈 A-8 B-1 0 5 = 2〇〇 -98- 200825468 【表7】（其2)Second optical film center brightness uniformity viewing angle (°) Relationship between the maximum diffusion direction of the first optical film and the maximum diffusion direction of the second optical film Screen vertical screen Horizontal embodiment 5-1 B-6 AAAA Example 5 - 2 B-6 AAAA Example 5-3 B-6 BAAA Example 5-4 B-6 CAAA Example 5-5 B-7 Vertical (Θ 6 2 90°) DAAA Example 5-6 B-8 CAAA Implementation Example 5-7 B-9 DAAA Example 5-8 B-6 BAAA Example 5-9 B-6 CAAA Comparative Example 5-1 B-6 EAAA Comparative Example 5-2 B-8 EAAA Comparative Example 5-3 B -9 EAAA Comparative Example 5-4 B-6 EAAA Comparative Example 5-5 B-6 EBAA Comparative Example 5-6 B-6 DAAA Example 6 B-6 AAAA Comparative Example 6 B-6 EAAA Example 7 B-6 AAAA Comparative Example 7 B-6 EAAA -96- 200825468 It is known from Table 6 that the embodiment of the present invention is 5-1 to 5-9, and the embodiment 6 and 7 even when the diffusion sheet is used as the second optical film. Any of the examples is good center brightness, superior uniformity, and viewing angle characteristics. Further, it was found that although the comparative examples 5 - 1, 5 · 2, 5 - 3 and Comparative Examples 6 and 7 using the isotropic diffusible sheets B-6, B-8, and B_9, good uniformity U and viewing angle were obtained. Features, but the center brightness is low. Further, in Comparative Example 5 - 4 in which the different direction diffusing sheet B-7 having a different divergence in the opposite direction (Dmax / Dmin = 1.6) was used, good uniformity u and viewing angle characteristics were obtained, but the center luminance was low. Further, it was found that even when the opposite-direction diffusion sheet was used, the relationship between the direction in which the light guide linear groove direction and the maximum diffusion direction of the first optical film were perpendicular was comparatively good, and the comparative example 5-6 and the non-parallel comparative example 5-6 were good. Uniformity U, viewing angle characteristics, but the center brightness is low. -97-200825468 [Table 7] (1) Light source light guide First optical film type Relationship between light guide linear groove direction and maximum diffusion direction of first optical film Example 8-1 LED single side 3 lamp A -8 B-1 Parallel (θ5=0ο) Example 8-2 LED Single Side 3 Lamp A-8 B-2 Parallel (0 5 = 0°) Example 8-3 LED Single Side 3 Lamp A-8 B- 3 Parallel (Θ 5 = 0.) Example 8-4 LED Single Side 3 Lamp A-8 B4 Parallel (θ5 = 0ο) Example 8-5 LED Single Side 3 Lamp A-8 B-1 Parallel (Θ 5 = 0.) Example 8-6 LED single side 3 lamp A-8 B-1 parallel (Θ 5 = 0.) Example 8-7 LED single side 3 lamp A-8 B-1 Parallel (θ5=0ο) Implementation Example 8-8 LED single side 3 lamp A-8 B-1 05 = 5. Example 8-9 LED single side 3 lamp A-8 B-1 0 5 = 10. Comparative Example 8-1 LED Single Side 3 Lamp A-8 B-6 Comparative Example 8-2 UED Single Side 3 Lamp A-8 B-8 Comparative Example 8-3 LED Single Side 3 Lamp A-8 B-9 Comparative Example 8-4 LED single-sided 3 lamps A-8 B-7 parallel (Θ5 = 〇.) Comparative example 8_5 led single 丨m boarded A-8 B-1 vertical ((9 5 = 90°) Comparative Example 8-6 LED single side 3 lamp A-8 B-1 0 5 = 2〇〇-98- 200825468 [Table 7] (2)

第2光學薄膜視野角（。）種類第1光學薄膜之最大擴散方向與第2 中心均勻度亮度畫面縱向晝面橫向光學薄膜之最大擴散方向的關係實施例8-1 Β-6 A A A A 實施例8-2 Β-6 A A A A 實施例8-3 Β-6 B A A A 實施例8-4 Β-6 C A A A 實施例8·5 Β-7 垂直（(97 = 90。） D A A A 實施例8-6 Β-8 C A A A 實施例8-7 Β-9 D A A A 實施例8-8 Β-6 B A A A 實施例8-9 Β-6 C A A A 比較例8-1 Β-6 E A A A 比較例8-2 Β-8 E A A A 比較例8-3 Β-9 E A A A 比較例8-4 Β-6 E A A A 比較例8-5 Β-6 E B A A 比較例8-6 Β-6 — D A A ASecond optical film viewing angle (.) Relationship between the maximum diffusion direction of the first optical film and the maximum diffusion direction of the second central uniformity luminance screen longitudinal pupil transverse optical film Example 8-1 Β-6 AAAA Example 8 -2 Β-6 AAAA Example 8-3 Β-6 BAAA Example 8-4 Β-6 CAAA Example 8·5 Β-7 Vertical ((97 = 90.) DAAA Example 8-6 Β-8 CAAA Example 8-7 Β-9 DAAA Example 8-8 Β-6 BAAA Example 8-9 Β-6 CAAA Comparative Example 8-1 Β-6 EAAA Comparative Example 8-2 Β-8 EAAA Comparative Example 8-3 Β-9 EAAA Comparative Example 8-4 Β-6 EAAA Comparative Example 8-5 Β-6 EBAA Comparative Example 8-6 Β-6 — DAAA

由表7得知：即使使用小尺寸的導光體，將擴散片作爲第2光學薄膜使用之情形，本發明構造之實施例8_丨〜中任一例均爲良好之中心亮度、具優越之均勻度、視野角特性。另外，得知：雖然使用等方向擴散性片b-6、B_8、 B-9之比較例8-1、8-2、8-3可以得到良好之均勻度 u、視野角特性’但是中心亮度爲低的。另外，使用異方向擴散 -99- 200825468 • 性小的異方向擴散片B - 7 ( D m a χ / D m i η = 1 . 6 )之比較例8 - 4 也可以得到良好之均勻度U、視野角特性，但是中心亮度爲低的。另外，得知：即使使用異方向擴散片，導光體線狀溝方向與第1光學薄膜最大擴散方向的關係爲垂直之比較例8 - 5及非平行之比較例8 - 6也可以得到良好之均勻度 U、視野角特性，但是中心亮度爲低的。 [產業上利用之可能性] 基於具優越之光利用效率、高亮度且廣視野角視野之 f K 觀點，本發明之面光源較習知之面光源爲優越，能夠適用於從背面照射液晶顯示元件之用途。另外，若使用本發明之面光源的話，作成高亮度且清晰之液晶顯示裝置成爲可能的。例如，其用途可列舉：行動電話、電子筆記本、筆記型PC、監視器、TV等。【圖式簡單說明】第1圖係顯示構成本發明面光源之各構件相對位置關係的分解斜視圖之一例。第2圖係顯示將光源配置於導光體3之二個以上側端面的例子之圖。第3圖係列舉從光射出面3 2側觀察本發明面光源之導光體3時之線狀溝3 3或線狀突起3 4的較佳配列形態之圖形。第4圖係列舉從光射出面3 2側觀察本發明面光源之導光體3時之線狀溝3 3或線狀突起3 4的較佳配列形態之圖 -100- 200825468 • 形。第5圖係說明本發明面光源之約略平行的線狀溝或線狀突起之圖。第6圖係列舉垂直於形成本發明面光源之導光體3的線狀溝3 3長邊方向之剖面圖。第7圖係列舉垂直於形成本發明面光源之導光體3的線狀突起34長邊方向之剖面圖。第8圖係說明半値幅定義之圖。 1 第9圖係說明線狀溝33或線狀突起34之長邊方向與第1光學薄膜5之異方向擴散性成爲最大之方向的夾角之圖。第1 0圖係顯示本發明面光源之第1光學薄膜較佳形態之斜視圖。第1 1圖係顯示本發明面光源之第2光學薄膜爲稜鏡片之情形的較佳形態之斜視圖。 f 第12圖係說明棱鏡之長邊方向與第1光學薄膜5之異方向擴散性成爲最大之方向的夾角之圖。第1 3圖係顯示本發明面光源之第2光學薄膜爲等方向性擴散片之情形的較佳形態之斜視圖。第1 4圖係說明稜鏡片光線透過特性之示意圖。第1 5圖係示意說明傳播於導光體內而射出之光之圖形。第1 6圖係本發明面光源於第2圖（a )之形態的情形 -101 - 200825468 . 下，顯示來自導光體3之光射出面32之中央部的射出角分布之一例。第1 7圖係本發明面光源於第2圖（a )之形態的情形下，顯示來自導光體3上之已設置第2光學薄膜之情形的中央部的射出角分布之一例。第1 8圖係顯示於實施例、比較例中之面光源亮度的測定點之示意圖。第1 9圖係示意表示於實施例、比較例中所製作之第1 Γ 光學薄膜形態之斜視圖。第20圖係示意表示於實施例、比較例中所製作之第1 光學薄膜形態之斜視圖。第2 1圖係示意表示於實施例、比較例中所製作之第1 光學薄膜形態之斜視圖。【主要元件符號說明】 1 光源 2 反射板 3 導光體 4 反射片 5 第 1 光學薄膜 6 第 2 光學薄膜 31 導光體 3 之光射入面 32 導光體 3 之光射出面 33 線狀溝 -102- 200825468 34 線狀突起 35 導光體3之光非射出面 101 亮度測定點 Η 1 線狀溝3 3的深度 Η2 線狀突起3 4的高度 θ 1 線狀溝3 3之光源1側之斜面與垂直於光源之直線的夾角It is known from Table 7 that even if a small-sized light guide is used and the diffusion sheet is used as the second optical film, any of the examples of the embodiment 8_丨~ of the present invention has a good central brightness and is superior. Uniformity and viewing angle characteristics. Further, it was found that although the comparative examples 8-1, 8-2, and 8-3 using the isotropic diffusible sheets b-6, B_8, and B-9 can obtain good uniformity u and viewing angle characteristics 'but the central brightness It is low. In addition, a good uniformity U and a field of view can be obtained by using the heterogeneous diffusion sheet of the different direction diffusion sheet B - 7 (D ma χ / D mi η = 1.6) which is different in the direction of diffusion -99-200825468. Angular characteristics, but the center brightness is low. Further, it was found that even when the opposite-direction diffusion sheet was used, the relationship between the direction in which the light guide linear groove direction and the maximum diffusion direction of the first optical film were perpendicular was Comparative Example 8.5 and the non-parallel Comparative Example 8-6 was good. Uniformity U, viewing angle characteristics, but the center brightness is low. [Possibility of industrial use] The surface light source of the present invention is superior to a conventional surface light source based on f K with superior light utilization efficiency, high brightness, and wide viewing angle field of view, and can be suitably used for illuminating a liquid crystal display element from the back side. Use. Further, when the surface light source of the present invention is used, it is possible to form a liquid crystal display device which is high in brightness and clear. For example, the use thereof includes a mobile phone, an electronic notebook, a notebook PC, a monitor, a TV, and the like. BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is an exploded perspective view showing the relative positional relationship of the members constituting the surface light source of the present invention. Fig. 2 is a view showing an example in which light sources are disposed on two or more side end faces of the light guide 3. Fig. 3 is a view showing a preferred arrangement of the linear grooves 3 3 or the linear protrusions 34 when the light guide 3 of the surface light source of the present invention is viewed from the light exit surface 3 2 side. Fig. 4 is a view showing a preferred arrangement of the linear grooves 3 3 or the linear protrusions 34 when the light guide 3 of the surface light source of the present invention is viewed from the side of the light exit surface 3 2 -100- 200825468 • Shape. Fig. 5 is a view showing a substantially parallel linear groove or a linear protrusion of the surface light source of the present invention. Fig. 6 is a cross-sectional view showing the longitudinal direction of the linear groove 3 3 perpendicular to the light guide 3 forming the surface light source of the present invention. Fig. 7 is a cross-sectional view showing the longitudinal direction of the linear projections 34 perpendicular to the light guide 3 forming the surface light source of the present invention. Figure 8 is a diagram illustrating the definition of a half-width. 1 is a view showing an angle between the longitudinal direction of the linear groove 33 or the linear protrusion 34 and the direction in which the diffusivity of the first optical film 5 in the opposite direction is maximized. Fig. 10 is a perspective view showing a preferred embodiment of the first optical film of the surface light source of the present invention. Fig. 1 is a perspective view showing a preferred embodiment of the case where the second optical film of the surface light source of the present invention is a cymbal. f Fig. 12 is a view showing an angle between the longitudinal direction of the prism and the direction in which the diffusivity of the first optical film 5 is maximized. Fig. 1 is a perspective view showing a preferred embodiment of the case where the second optical film of the surface light source of the present invention is an isotropic diffuser. Figure 14 is a schematic diagram showing the light transmission characteristics of the cymbal. Fig. 15 is a view schematically showing a pattern of light emitted from the light guide body. Fig. 16 is a view showing an example of the aspect of the surface light source of the present invention in the form of Fig. 2(a) -101 - 200825468. Next, an example of the distribution of the exit angle from the central portion of the light exit surface 32 of the light guide 3 is shown. In the case of the surface light source of the present invention, in the form of Fig. 2(a), an example of an emission angle distribution from the central portion of the light guide 3 in which the second optical film is provided is shown. Fig. 18 is a view showing the measurement points of the luminance of the surface light source in the examples and the comparative examples. Fig. 19 is a perspective view showing the form of the first optical film produced in the examples and the comparative examples. Fig. 20 is a perspective view schematically showing the form of the first optical film produced in the examples and the comparative examples. Fig. 2 is a perspective view schematically showing the form of the first optical film produced in the examples and the comparative examples. [Description of main components] 1 light source 2 reflector 3 light guide 4 reflection sheet 5 first optical film 6 second optical film 31 light incident surface 32 of light guide 3 light exit surface 33 of light guide 3 linear Groove-102- 200825468 34 Linear protrusion 35 Light non-ejecting surface 101 of light guide 3 Brightness measurement point Η 1 Depth of linear groove 3 3 高度 2 Height of linear protrusion 3 4 θ 1 Light source of linear groove 3 3 The angle between the side slope and the line perpendicular to the light source

C u Θ 2 相對於線狀突起3 4之光源1之斜面與垂直於光源之直線的夾角 Θ 3 稜鏡片之頂角 Θ 4 相鄰接之線狀溝3 3或線狀突起3 4之長邊方向延長線的夾角 0 5 線狀溝3 3或線狀突起3 4之長邊方向（d 1 )與第1光學薄膜5之異方向擴散性成爲最大之方向（d2 )的夾角 θ 6 稜鏡之長邊方向（d3)與第1光學薄膜5之異方向擴散性成爲最大之方向（d 2 )的夾角 Θ i 射入角射出角 dl 線狀溝3 3或線狀突起3 4之長邊方向 d2 異方向擴散性成爲最大之方向 d3 稜鏡之長邊方向 λ 11 從法線方向射入棱鏡片之光 -103- 200825468 ^ λ ι2 最適於稜鏡片之射入光 λ i3 以大的射入角射入棱鏡片之光 λ p 1 與導光體3表面約略平行地撞擊線狀溝3 3或線狀突起3 4之光 λ p 2 從與導光體3之光射出面3 2側撞擊線狀溝3 3 或線狀突起3 4之光 λ p 3 從與導光體3之光射出面32相反面側撞擊線 f \ λ ο 1 狀溝3 3或線狀突起3 4之光與導光體3約略平行地撞擊線狀溝3 3或線狀突起34之光，射向導光體3外之光 λ 〇2 從與導光體3之光射出面3 2側撞擊線狀溝3 3 或線狀突起34之光，射向導光體3外之光 λ 〇3 從與導光體3之光射出面32相反面側撞擊線片犬溝33或線狀突起34之光，射向導光體3外之光 c FL1 第1光學薄膜的厚度 FL2 第2光學薄膜的厚度 -104-C u Θ 2 The angle between the slope of the light source 1 with respect to the linear protrusion 34 and the line perpendicular to the light source Θ 3 The apex angle 稜鏡 of the Θ 4 The length of the adjacent linear groove 3 3 or the linear protrusion 3 4 The angle θ 6 of the linear extension groove 3 3 or the longitudinal direction (d 1 ) of the linear projection 3 4 and the direction (d2) in which the diffusivity of the first optical film 5 is the largest is the largest angle (d2) An angle Θ i between the longitudinal direction of the mirror (d3) and the direction (d 2 ) in which the diffusivity of the first optical film 5 is the largest is the incident angle dl of the linear groove 3 3 or the linear protrusion 34 The side direction d2 is diffused in the opposite direction to the maximum direction d3 The long side direction λ 11 is incident on the prism sheet from the normal direction -103- 200825468 ^ λ ι2 The most suitable for the incident light λ i3 of the cymbal The light λ p 1 incident on the prism sheet and the light λ p 2 striking the linear groove 3 3 or the linear protrusion 3 4 in parallel with the surface of the light guide 3 from the light exit surface 3 2 of the light guide 3 The light λ p 3 of the side impact linear groove 3 3 or the linear protrusion 3 4 strikes the line f \ λ ο 1 groove 3 3 from the side opposite to the light exit surface 32 of the light guide 3 The light of the protrusions 34 hits the light of the linear groove 3 3 or the linear protrusion 34 approximately parallel to the light guide 3, and the light λ 〇 2 emitted from the light guide 3 is emitted from the light exit surface 3 of the light guide 3 The light that strikes the linear groove 3 3 or the linear protrusion 34 on the side 2 strikes the light beam λ 〇 3 outside the light guide 3 from the opposite side of the light exit surface 32 of the light guide 3 to the wire dog groove 33 or linear The light of the protrusion 34, the light outside the light guide 3 c FL1 The thickness of the first optical film FL2 The thickness of the second optical film -104-

Claims

200825468 十、申請專利範圍： 1 . 一種面光源，其係具備：光源、具有相對該光源之至少一光射入面與約略與其垂直之光射出面的導光體、與相對於該光射出面所配置之第1光學薄膜；於該導光體中，在該光射出面或是該光射出面之背面的光非射出面上，約略平行地設置複數個線狀溝或線狀突起；該第1光學薄膜係具有異方向擴散性，以使此異方向 C < 擴散性成爲最大之方向約略平行於該線狀溝或線狀突起的長邊方向之方式來予以配置。 2 ·如申請專利範圍第1項之面光源，其中該線狀溝或線狀突起係垂直於其長邊方向之剖面形狀爲從約略圓弧狀、約略吊鐘狀、約略三角形與約略梯形所構成族群中所選出之至少一種。 3 .如申請專利範圍第1項之面光源，其中該線狀溝或線狀突起係其長邊方向約略平行於該導光體之光射入面。 4·如申請專利範圍第1項之面光源，其中該線狀溝或線狀突起係設置在該導光體之光非射出面上。 5 ·如申請專利範圍第1項之面光源，其中在該第1光學薄膜上設置第2光學薄膜。 6.如申請專利範圍第1項之面光源，其中該第1光學薄膜係於使光從法線方向射入此第1光學薄膜時之擴散性成爲最大之方向上的透過光半値幅D1 max，與擴散性成爲 -105- 200825468 最小之方向上的透過光半値幅Dlmin之比Dlmax/Dlmin 爲3以上。 7 ·如申請專利範圍第1項之面光源，其中該第1光學薄膜之反射率爲45%以上，霧度爲70%以上。 8. 如申請專利範圍第6項之面光源，其中該第1光學薄膜之該半値幅Dlmin爲10°以下。 9. 如申請專利範圍第5項之面光源，其中該第2光學薄膜之頂角爲8 0。〜1 0 0 °的稜鏡片。 f 〜 10.如申請專利範圍第9項之面光源，其中該棱鏡片係使其長度（導光）方向，與使光從法線方向射入該第1光學薄膜上時之擴散性成爲最大之方向形成約略平行之方式來予以配置。 1 1 .如申請專利範圍第9項之面光源，其中位於該導光體所設置之線狀溝的光源側之斜面與垂直於該光源之直線的夾角，或是位於導光體所設置之線狀突起的光源相反側 < 之斜面與垂直於該光源之直線的夾角爲42.5°〜50°。 12.如申請專利範圍第5項之面光源，其中該第2光學薄膜係於使光從法線方向射入此第2光學薄膜時之擴散性成爲最大之方向上的透過光半値幅D2max，與擴散性成爲最小之方向上的透過光半値幅D2min之比D2max/D2min 爲5以上。 1 3.如申請專利範圍第1 2項之面光源，其中該第2光學薄膜之反射率爲50%以上，霧度爲70%以上。 -106- 200825468 1 4 .如申請專利範圍第1 2項之面光源，其中該第膜之該半値幅D2min爲π〜50°以下。 1 5 .如申請專利範圍第1 2項之面光源，其中位於所設置之線狀溝的光源側之斜面與垂直於該光的夾角’或是位於導光體所設置之線狀突起的側之斜面與垂直於該光源之直線的夾角爲2〇。、 1 6 · —種液晶顯示裝置，其係裝載如申請專利範圍面光源。 2光學薄該導光體源之直線光源相反 -42.5° ° 第1項之 -107-200825468 X. Patent Application Range: 1. A surface light source comprising: a light source; a light guide body having at least one light incident surface opposite to the light source and a light exit surface perpendicular thereto; and a light exiting surface opposite to the light emitting surface a first optical film disposed; wherein the light guide body has a plurality of linear grooves or linear protrusions disposed approximately in parallel on the light exit surface or the light non-ejecting surface on the back surface of the light exit surface; The first optical film has a different direction diffusing property, and the direction in which the different direction C < diffusibility is maximized is approximately parallel to the longitudinal direction of the linear groove or the linear protrusion. 2) The surface light source of claim 1, wherein the linear groove or the linear protrusion has a cross-sectional shape perpendicular to a longitudinal direction thereof, which is approximately arcuate, approximately bell-shaped, approximately triangular, and approximately trapezoidal At least one selected from the group is formed. 3. The surface light source of claim 1, wherein the linear groove or the linear protrusion has a longitudinal direction that is approximately parallel to a light incident surface of the light guide. 4. The surface light source of claim 1, wherein the linear groove or the linear protrusion is disposed on a light non-ejecting surface of the light guiding body. 5. The surface light source of claim 1, wherein the second optical film is provided on the first optical film. 6. The surface light source according to claim 1, wherein the first optical film is a transmitted light half-web D1 max in a direction in which diffusibility is maximized when light is incident on the first optical film from a normal direction. The ratio Dlmax/Dlmin of the transmitted light half-web Dlmin in the direction of the minimum of -105-200825468 is 3 or more. 7. The surface light source of claim 1, wherein the first optical film has a reflectance of 45% or more and a haze of 70% or more. 8. The surface light source of claim 6, wherein the half-web Dlmin of the first optical film is 10 or less. 9. The surface light source of claim 5, wherein the apex angle of the second optical film is 80. ~1 0 0 ° 稜鏡. f. The surface light source of claim 9, wherein the prism sheet has a length (light guiding) direction and a maximum diffusivity when the light is incident on the first optical film from the normal direction. The directions are formed in a manner that is approximately parallel. 1 1 . The surface light source of claim 9 , wherein a slope of a light source side of the linear groove provided by the light guide body is at an angle perpendicular to a line perpendicular to the light source, or is disposed at a light guide body The angle between the inclined surface of the opposite side of the light source of the linear protrusion and the line perpendicular to the light source is 42.5° to 50°. 12. The surface light source of claim 5, wherein the second optical film is a transmitted light half-web D2max in a direction in which diffusivity is maximized when light is incident on the second optical film from a normal direction, The ratio D2max/D2min of the transmitted light half-web D2min in the direction in which the diffusibility is the smallest is 5 or more. 1) The surface light source of claim 12, wherein the second optical film has a reflectance of 50% or more and a haze of 70% or more. -106-200825468 1 4. The surface light source of claim 12, wherein the half-web D2min of the first film is π~50° or less. 1 5 . The surface light source of claim 12, wherein a slope of the light source side of the disposed linear groove is perpendicular to the angle of the light or a side of the linear protrusion disposed on the light guide body The angle between the slope and the line perpendicular to the light source is 2 〇. , a liquid crystal display device, which is loaded with a surface light source as claimed in the patent application. 2 optical thin The light source source line The opposite source -42.5 ° ° Item 1 -107-