201007218 九、發明說明: * 【發明所屬之技術領域】 本發明係一種兼具聚光及擴散之複合型光學膜片之微 結構,尤指一種用於背光模組之光學膜片,可減少膜片使 用數、降低成本,以及具有光學輝度提升與增加光利用率 之功能。 【先前技術】 ❿ 按,目前在平面顯示器中,主要包含有TFT-LCD顯示 器、PDP電漿顯示器及背投影顯示器。由於日、韓及台灣 大廠積極投入TFT-LCD液晶顯示器發及採用大型化的生產 設備,液晶顯示器的品質不斷精進下,價格亦不斷下滑, 帶動了液晶顯示器的需求,如此使TFT-LCD顯示器成為目 前平面顯示器的主流。 而液晶面板本身無法發出光線,需要藉由背光模組來 提供顯示器之光源,一般而言,液晶顯示器的背光源主要 Q 是採直下式,而直下式背光源可以藉由燈管的增加,或使 用擴散片來達到大尺寸液晶顯示器的亮度要求;其中,擴 散片分為内部擴型及表面擴散型。内部擴散型是在一壓克 .力樹脂板内分散有不同折射率的光學顆粒,使光線均勻性 地反射,此時光線因光學顆粒之折射率不同以及混合的百 分比等因素,進行晝面亮度及輝度不均勻性的調整;而表 面擴散型則為使用一透明之樹脂板之表面粗糙化,使光線 反射及折射。 請參閱台灣專利公告第M266466號『增加亮度之光擴 201007218 散板之結構』,其中揭露出習知之直下式背光模組之結構, '一般直下式模組,其構造包含了一反射片、複數個光源、 一光擴散片、一第一棱鏡片、一第二棱鏡片、一光擴散膜 等。目前在背光模組中,常見的增亮技術是搭配一片或兩 片不同方向的棱鏡片,其原理乃是利用稜鏡之折射率以及 棱鏡角度將入射光線折射後,通過鋸齒狀的光出射面控制 其射出角度,讓原先經由擴散片而擴散開來的光線再度集 中,並減少光耗損率,而達到增加亮度之目的。棱鏡片一 ❹般是用PET聚酯或聚碳酸脂材料製成75〜230 /zm的薄片, 在薄片的表面形成間距為24〜110//m,頂角為90〜110度的 長條狀稜鏡陣列,因其光學結構以及折射率,而具有聚光 的作用。當使用一片直角形狀的棱鏡片時,則正面亮度可 改善1. 6倍以上,若使用兩片呈垂直排列的稜鏡片,則正 面亮度可改善2倍以上;相關專利尚可參閱美國已公告專 利第 5175030、5183597、6280063、627747卜 5592332 號, 皆對增亮、擴散技術有進一步描述。 ❹ 然而,稜鏡片表面呈直角狀之頂角極容易在製造、運 送時不慎被碰撞而受損,而頂角任一部位受損即會在顯示 器面板上形成亮點等重大瑕疵,無法被使用者所接受’且 製造良率較低,亦造成製造業者極大困擾;因此又有一種 習知作法係於了員角最尖端部分以削平或導圓角方式來處 理,使頂角較不容易受損,從而提升製作良率,但此種作 法又會使該棱鏡片之聚光效果大打折扣’無法提供足夠亮 度之背光源;立習知技術係將增光及光擴散分開處理,分 別以一擴散片以及一或二片增光板之組合,來同時達成增 201007218 光及擴散之目的,無法將其整合在一起,亦大幅提高製造 成本。 【發明内容】 本發明,其主要目的係為提供一種用於背光模組之光 學膜片,可減少膜片使用數、降低成本,以及具有光學輝 度提升與增加光利用率之功能。 為達上述目的,本發明之光學膜片主要設有一基材, ❹該基材設有相對設置之上、下表面,該上表面設有複數微 結構;其中,各微結構係具有弧形表面,且該微結構之長 軸及短軸長度係介於20 μ m〜50 # m,而高度則介於 10 〜35//m,在每米平方依實際試驗結果此複合型光學膜 輝度值可比一般業界所使用之高輝度擴散膜增加約 12%〜20%之輝度,全線透光率為55%〜60%的範圍,霧度為 85%〜90%的範圍,以具有光學輝度提升以及增加光利用率之 功能。 【實施方式】 為了讓本發明之上述之目的、功能特徵、和優點能更 明確被暸解,下文將本發明以較佳之實例,並配合所附圖 式,作詳細說明如下: 本創作「兼具聚光及擴散複合型光學膜片之微結構及 背光模組」該光學膜片1如第一圖之第一實施例所示,主 要設有一基材11,該基材11設有相對設置之上、下表面 111、112,該上表面111設有複數微結構12,各微結構12 201007218 分佈比例可以為92%以上,其中各微結構12係具有弧形表 面121 ’各微結構12係凸出(或凹入)該上表面111,而各 微結構弧形表面121之曲率可介於0. 015〜0. 025之間,請 同時參閱第二圖及第三圖所示,且該微結構12之長軸[及 短轴W長度係介於20 // m〜50 /zm,而高度Η則介於 10//in〜35/z m ;當然,該基材11可進一步設有一抗靜電密 著層13,如第四圖之第二實施例所示,該抗靜電密著層13 係設置於該基材11之下表面112 ;另外’亦可於該基材u ❿之下表面112進一步設有複數微結構12,如第五圖之第三 實施例所示。 再者’亦可於上述各實施例之微結構及/或抗靜電密著 層中設有複數擴散粒子,以第二實施例為例,該基材上下 表面111設有複數微結構12,而下表面112則設有—抗靜 電密著層13 ’如第六圖之第四實施例所示,各微結構12 及抗靜電密著層13中係設有複數擴散粒子14,該擴散粒 子Η可以為球狀(亦可以為非球狀),該擴散粒子14係選 ❿自但不限於卯、?8、?1^八、尼龍、矽膠之材質,而該擴散 粒子14平均粒徑可以為0· lnm〜lOOOnm,各擴散粒子14係 部份埋設或凸設於微結構12及抗靜電密著層13,藉由各 擴散粒子14之設置可進一步增加光學膜片之擴散能力;备 然,該擴散粒子亦可以為高分子材料所構成之中空球: #球狀之結構體’如第七圖之第五實施例所示,該擴^ 子14係為高分子材料所構成之中空球狀結構體,誃: 子14係由二種不同折射率的材料所構成4 ^過^ 散粒子14時,會形成四次光折射路徑,使通過之光 201007218 更均勻化。 ‘ 另外,各微結構12之排列方式可如第一圖所示,係沿 長軸方向,以彼此平行、相鄰而不連續之方式排列,亦可 以如第八圖之第六實施例所示,各微結構12係沿長軸方 向,以彼此垂直、相鄰而不連續之方式排列。 當然,除了上述各實施例中增加擴散粒子來增加擴散 能例外,亦可於光學膜片上增加增光層以達到增亮之效 果,如第九圖之第七實施例所示,該基材之下表面112進 © —步設有一增光層15,該增光層15設有複數稜鏡結構 151,用以增加光學膜片之亮度。 其中,本發明光學膜片之製造方法,如第十圖所示可 以包含下列步驟: 步驟A :提供一第一基材31,如第十一圖(A)所示,該 第一基材31可以為PET材質; 步驟B :於該第一基材31其中一表面形成有複數微結 構32 ; ❹ 步驟C :於各微結構32表面覆蓋一層UV膠33,如第 十一圖(B)所示; 步驟D :於該UV膠33表面設置一第二基材34而形成 一半成品,如第十一圖(C)所示; 步驟E :進行硬化步驟,將步驟D之半成品照射紫外 線使該UV膠33形成硬化作用,令該UV膠33形成與各微 結構32相對應之成型層35,如第十一圖(D)所示; 步驟F :最後由微結構32與該成型層35相互分離, 而形成有二片光學膜片,如第十一圖(E)所示,其中一光學 201007218 膜片係具有第一基材31,該第一基材31表面形成有複數 * 凸出表面之微結構32,另外一光學膜片則具有第二基材 34,該第二基材34表面之成型層35形成有複數凹入表面 之微結構36;藉由上述製造方法可同時製造出二個光學膜 片,其製程較為簡便。 本發明之光學膜片係可應用於背光模組中,如第十二 圖所示係為本發明應用於側光式背光模組,該背光模組2 至少包含有;一載具21、一光源裝置22、導光板23以及 © 至少一光學膜片1,該載具21係可供承載光源22或光學 膜片1之結構體,該光源裝置22係包括至少一光源221並 裝設於載具21側邊,而該導光板23則設置於光源裝置22 側邊,該光學膜片1係設於該載具21上並設於導光板23 上方,該光學膜片1之結構可以為上述各實施例所述之結 構,而本圖係以第一實施例為例;本發明之光學膜片亦可 應用於直下式背光模組,如第十三圖所示,該背光模組2 同樣至少包含有;一載具21、一光源裝置22、導光板23 〇 以及至少一光學膜片1,該光源裝置22係裝設於載具21 上方,而該導光板23及光學膜片1則依序設置於光源裝置 22上方;當然,可視所需增加光學膜片之數量,且各光學 膜片可以相同形式或不同形式,例如各光學膜片可以均為 設有凸出表面或凹入表面之微結構,或者可以為設有凸出 表面以及凹入表面之微結構,亦或者於該光學膜片上方進 一步設有至少一增光膜及/或擴散膜(圖中未標示),來增加 背光模組之亮度及/或光擴散效果。 本發明之光學膜片相較於習有係具有下列優點: 201007218 1、 該光學膜片應用於背光模組中可減少膜片使用數, 降低成本,具有光均勻與增加光之利用率之功能。 2、 在每米平方依實際試驗結果此光學膜片之輝度值可 比一般業界所使用之高輝度擴散膜增加約12%〜20%之輝 度,全線透光率為55%〜60%的範圍,霧度為85%〜90%的範 圍’若高於或低於此範圍輝度值則會降低。 3、該光學膜片之單位面積上微結構分佈比例為92%以 上’以使整體光均勻度為80%〜92%。 ❹ 如上所述,本發明提供一種較佳可行之兼具聚光及擴 散複合型光學膜片之微結構,爰依法提呈發明專利之申 t惟二上之實施說明及圖式所示’係本發明較佳實施 裝置、特徵等近似、雷因* “ f 〃本發月之構&、 申請專利範圍之内。°者鏡屬本發明之創設目的及 【圖式簡單說明】 g。第—圖係為本發明中光學膜片第-實施例之結構立體 匕=本發明中微結構之放大結構示意圖。 圖。 糸為本發明中光學膜片第—實施例之結構示意 圖 圖 第四圖係為本發明中光學膜片第二實施例之結構示意 圖係為本發明中光學膜片第三實施例之結構示意 201007218 第六圖係為本發明中光學膜片第四實施例之結構示意 圖。 第七圖係為本發明中光學膜片第五實施例之結構示意 圖 圖 ❹ 意圖 第八圖係為本發明中光學膜片第六實施例之結構示 第九圖係為本發明中光學膜片第七實施例之結構示 第十圖係為本發明中光學W製造方法之流程方塊 意 意 苐十一圖(A)〜(E)係為本發曰月 流程結構示意圖。 +光學膜片製造方法 之 第十二圖係為本發明中光學腺H 組之結構示意圖。 學W應用於侧光式背光模 第十三圖係為本發明中光學滕 組之結構示意圖。 ,心應用於直下式背光模 ❹ 【主要元件代表符號說明201007218 IX. Description of the invention: * Technical field of the invention The present invention relates to a microstructure of a composite optical film having both light collecting and diffusion, and more particularly to an optical film for a backlight module, which can reduce the film. The number of pieces used, the cost reduction, and the function of optical brightness enhancement and increased light utilization. [Prior Art] ❿ Press, currently in the flat panel display, mainly includes a TFT-LCD display, a PDP plasma display, and a rear projection display. As Japanese, Korean and Taiwanese manufacturers actively invest in TFT-LCD liquid crystal displays and use large-scale production equipment, the quality of liquid crystal displays continues to improve, and prices continue to decline, driving the demand for liquid crystal displays, thus enabling TFT-LCD displays. Become the mainstream of current flat panel displays. The liquid crystal panel itself cannot emit light, and the backlight module is required to provide the light source of the display. Generally, the backlight of the liquid crystal display is mainly a direct type, and the direct type backlight can be increased by a light tube, or Diffusion sheets are used to achieve the brightness requirements of large-size liquid crystal displays; among them, the diffusion sheets are classified into an internal expansion type and a surface diffusion type. The internal diffusion type is an optical particle in which a different refractive index is dispersed in a pressure resin plate, so that the light is uniformly reflected. At this time, the light is subjected to the brightness of the surface due to the difference in refractive index of the optical particles and the percentage of mixing. And the adjustment of the luminance unevenness; and the surface diffusion type is the surface roughening using a transparent resin plate to reflect and refract light. Please refer to Taiwan Patent Publication No. M266466, "Enhanced Brightness Light Expansion 201007218 Dispersion Plate Structure", which reveals the structure of the conventional direct type backlight module, 'general direct type module, whose structure contains a reflection sheet, plural a light source, a light diffusing sheet, a first prism sheet, a second prism sheet, a light diffusing film, and the like. At present, in the backlight module, the common brightening technique is to match one or two prism sheets in different directions. The principle is to refract incident light by using the refractive index of the crucible and the prism angle, and pass the jagged light exit surface. Controlling the angle of the shot, so that the light diffused through the diffuser is again concentrated, and the light loss rate is reduced, thereby increasing the brightness. The prism sheet is made of a sheet of 75 to 230 /zm made of PET polyester or polycarbonate material, and a strip having a pitch of 24 to 110 / / m and a vertex angle of 90 to 110 degrees is formed on the surface of the sheet. The tantalum array has a function of collecting light due to its optical structure and refractive index. When a rectangular prism sheet is used, the front luminance can be improved by 1.6 times or more. If two vertically arranged cymbals are used, the front luminance can be improved by more than 2 times; Further, the highlighting and diffusion techniques are further described in Nos. 5175030, 5183597, 6280063, 627747, and 5592332. ❹ However, the apex angle of the surface of the cymbal is extremely easy to be damaged by collision during manufacturing and transportation. If any part of the apex is damaged, it will form a bright spot on the display panel and cannot be used. The acceptance is 'and the manufacturing yield is low, which also causes great trouble to the manufacturers; therefore, there is a conventional practice in which the tip end of the staff corner is treated by flattening or rounding, so that the top angle is less susceptible. Loss, thereby improving the production yield, but this method will greatly reduce the concentrating effect of the prism sheet 'can not provide a sufficient brightness backlight; the learning technology is to separate the addition and light diffusion, respectively, to spread The combination of a film and one or two brightness-increasing plates simultaneously achieves the goal of increasing 201007218 light and diffusion, and cannot be integrated together, which also greatly increases manufacturing costs. SUMMARY OF THE INVENTION The present invention is mainly directed to an optical film for a backlight module, which can reduce the number of diaphragms used, reduce the cost, and has the functions of enhancing optical brightness and increasing light utilization. In order to achieve the above object, the optical film of the present invention is mainly provided with a substrate, and the substrate is provided with opposite upper and lower surfaces, and the upper surface is provided with a plurality of microstructures; wherein each of the microstructures has a curved surface And the length of the long axis and the short axis of the microstructure is between 20 μm and 50 # m, and the height is between 10 and 35//m, and the luminance of the composite optical film is obtained according to the actual test result per square meter. It can increase the brightness of the high-luminance diffusing film used by the general industry by about 12%~20%, the whole line transmittance is in the range of 55%~60%, and the haze is in the range of 85%~90%, so as to have the optical brightness enhancement and Increase the function of light utilization. The above-described objects, features, and advantages of the present invention will become more apparent from the aspects of the invention. The microstructure and backlight module of the concentrating and diffusing composite optical film. The optical film 1 is mainly provided with a substrate 11 as shown in the first embodiment of the first figure, and the substrate 11 is provided with a relative arrangement. Upper and lower surfaces 111, 112, the upper surface 111 is provided with a plurality of microstructures 12, each of the microstructures 12 201007218 may have a distribution ratio of 92% or more, wherein each of the microstructures 12 has a curved surface 121' each microstructure 12 system convex The radii of the curved surface 121 may be between 0. 015~0. 025, please refer to the second and third figures at the same time, and the micro The long axis [and the short axis W length of the structure 12 are between 20 // m~50 /zm, and the height Η is between 10//in and 35/zm; of course, the substrate 11 can be further provided with an antistatic The adhesion layer 13, as shown in the second embodiment of the fourth figure, the antistatic adhesion layer 13 is disposed on the 11 below material surface 112; additional 'u also to the substrate surface under ❿ 112 is further provided with a plurality of microstructures 12, as shown in the third example of the fifth embodiment of FIG. Furthermore, a plurality of diffusion particles may be provided in the microstructure and/or antistatic adhesion layer of the above embodiments. In the second embodiment, the upper and lower surfaces 111 of the substrate are provided with a plurality of microstructures 12, and The lower surface 112 is provided with an antistatic adhesion layer 13'. As shown in the fourth embodiment of the sixth figure, the plurality of diffusion particles 14 are disposed in each of the microstructures 12 and the antistatic adhesion layer 13, and the diffusion particles are It may be spherical (or non-spherical), and the diffusing particles 14 are selected from, but not limited to, 卯,? 8,? 1^8, nylon, silicone material, and the average particle diameter of the diffusion particles 14 may be 0·lnm~lOOOnm, each diffusion particle 14 is partially embedded or protruded from the microstructure 12 and the antistatic adhesion layer 13, The diffusing ability of the optical film can be further increased by the arrangement of the respective diffusing particles 14; in addition, the diffusing particles can also be hollow spheres composed of a polymer material: #spherical structure" as the fifth embodiment of the seventh figure In the example, the expansion 14 is a hollow spherical structure composed of a polymer material, and the 誃: 14 is composed of two materials having different refractive indices. The secondary light refraction path makes the passing light 201007218 more uniform. In addition, the arrangement of the microstructures 12 may be arranged in parallel, adjacent and discontinuous manner along the long axis direction as shown in the first figure, or may be as shown in the sixth embodiment of the eighth figure. Each of the microstructures 12 is arranged in a direction perpendicular to the long axis, perpendicular to each other, adjacent to each other. Of course, in addition to the above embodiments, the diffusion particles are added to increase the diffusion energy, and the brightness enhancement layer may be added to the optical film to achieve the brightness enhancement effect. As shown in the seventh embodiment of the ninth embodiment, the substrate is The lower surface 112 is provided with a light-increasing layer 15, and the light-increasing layer 15 is provided with a plurality of germanium structures 151 for increasing the brightness of the optical film. The method for manufacturing the optical film of the present invention, as shown in the tenth figure, may comprise the following steps: Step A: providing a first substrate 31, as shown in FIG. 11(A), the first substrate 31 The material may be PET; Step B: a plurality of microstructures 32 are formed on one surface of the first substrate 31; ❹ Step C: a surface of each microstructure 32 is covered with a layer of UV glue 33, as shown in FIG. 11(B) Step D: a second substrate 34 is disposed on the surface of the UV adhesive 33 to form a semi-finished product, as shown in FIG. 11(C); Step E: performing a hardening step, and irradiating the semi-finished product of the step D with ultraviolet rays to make the The UV glue 33 forms a hardening effect, so that the UV glue 33 forms a molding layer 35 corresponding to each microstructure 32, as shown in FIG. 11(D); Step F: Finally, the microstructure 32 and the molding layer 35 are mutually Separating, and forming two optical films, as shown in FIG. 11(E), wherein one optical 201007218 film has a first substrate 31, and the surface of the first substrate 31 is formed with a plurality of * convex surfaces. The microstructure 32, the other optical film has a second substrate 34, and the molding layer 35 on the surface of the second substrate 34 There are recessed into the plurality of microstructured surface 36; at the same time by the above-described method for producing an optical film produced two sheets, which process is simple. The optical film of the present invention can be applied to a backlight module. As shown in FIG. 12, the present invention is applied to an edge-lit backlight module, and the backlight module 2 includes at least one carrier 21 and one The light source device 22, the light guide plate 23, and the at least one optical film 1 are used to carry the structure of the light source 22 or the optical film 1. The light source device 22 includes at least one light source 221 and is mounted on the carrier. The light guide plate 23 is disposed on the side of the light source device 22, and the optical film 1 is disposed on the carrier 21 and disposed above the light guide plate 23. The structure of the optical film 1 may be the above The structure described in each embodiment, and the figure is taken as an example in the first embodiment; the optical film of the present invention can also be applied to a direct type backlight module, as shown in the thirteenth figure, the backlight module 2 is the same The light source device 22 is mounted on the carrier 21, and the light guide plate 23 and the optical film 1 are included in the vehicle 21, a light source device 22, a light guide plate 23, and at least one optical film 1. Sequentially disposed above the light source device 22; of course, the number of optical films may be increased as needed, and Each of the optical films may be in the same form or in different forms. For example, each of the optical films may be a microstructure having a convex surface or a concave surface, or may be a microstructure having a convex surface and a concave surface, or Further, at least one brightness enhancement film and/or a diffusion film (not shown) is disposed on the optical film to increase the brightness and/or light diffusion effect of the backlight module. The optical film of the present invention has the following advantages compared with the conventional system: 201007218 1. The optical film is applied to the backlight module to reduce the number of diaphragms used, reduce the cost, and have the function of uniformity of light and increase utilization of light. . 2. In the square test per square meter, the luminance value of the optical film can be increased by about 12% to 20% than that of the high-intensity diffusion film used in the industry, and the full-line transmittance is in the range of 55% to 60%. The range of haze is 85% to 90% 'if the brightness value is higher or lower than this range, it will decrease. 3. The microstructure distribution ratio per unit area of the optical film is 92% or more so that the overall light uniformity is 80% to 92%. ❹ As described above, the present invention provides a preferred and feasible micro-structure of a concentrating and diffusing composite optical film, and an implementation specification and a schematic diagram of the invention are provided in accordance with the law. The preferred embodiment of the present invention, the features and the like are similar, the Rayin* "f 〃 发 发 之 & & 、 、 、 、 、 ° ° ° 者 者 者 者 者 者 者 者 者 者 者 者 者 者 者 者 者 者 者 者 者 者 者 者 者 者 者 者- The figure is the structure of the optical film of the first embodiment of the present invention. FIG. 3 is a schematic view showing the enlarged structure of the microstructure of the present invention. FIG. 4 is a schematic view of the structure of the optical film of the present invention. The structural schematic view of the second embodiment of the optical film of the present invention is the structural schematic of the third embodiment of the optical film of the present invention 201007218. The sixth figure is a schematic structural view of the fourth embodiment of the optical film of the present invention. 7 is a schematic structural view of a fifth embodiment of an optical film in the present invention. FIG. 8 is a view showing the structure of a sixth embodiment of the optical film of the present invention. FIG. 9 is an optical film of the present invention. Seventh reality The tenth embodiment of the structure of the embodiment is the flow block of the optical W manufacturing method of the present invention. The eleventh figure (A) to (E) are schematic diagrams of the flow structure of the present invention. The twelfth figure is a schematic view of the structure of the optical gland group H in the present invention. The thirteenth figure applied to the edge-light type backlight mode is a schematic structural view of the optical tanning group in the present invention. The core is applied to the direct-type backlight mode. ❹ [Main component representative symbol description
長軸L 短軸W 高度fi 光學膜片1 上表面111 下表面112 微結構12 201007218 弧形表面121 . 抗靜電密著層13 擴散粒子14 增光層15 載具21 光源裝置22 光源221 導光板23 ❹第一基材31 微結構32 UV 膠 33 第二基材34 成型層35 微結構36Long axis L Short axis W Height fi Optical film 1 Upper surface 111 Lower surface 112 Microstructure 12 201007218 Curved surface 121. Antistatic adhesion layer 13 Diffusion particles 14 Lightening layer 15 Carrier 21 Light source device 22 Light source 221 Light guide plate 23 ❹ first substrate 31 microstructure 32 UV glue 33 second substrate 34 molding layer 35 microstructure 36