200809264 九、發明說明： 【發明所屬之技術領域】 本發明係關於一種具有優異的光學擴散性、高均勻 性的擴散板，是一種將板材表面成形為不同形狀之立體 結構，利用板材表面不同的立體結構及添加不同的擴散 劑來達到改變光的行進路徑，在背光模組中將冷陰極管 (CCFL)所發出來的光線均勻分散，並可減少冷陰極管所 使用的數量，以提供光線從出光面出來後達到光學均勻 Φ 性的效果。 【先前技術】 隨著數位電視的普及，這幾年顯示器的競爭中，液 晶顯示器一直是受到高度重視，以及高度的成長性。液 晶顯示器中其成象是依據電場的開關而驅動出所顯現 的畫面，液晶面板本身並不會發出光線，需藉由背光模 組來提供顯示器光源。一般而言，應用在大尺寸的液晶 顯示器上均為直下式光源，直下式背光源可以藉由燈管 φ 的增加，與擴散元件的設計來達到高亮度與均勻光源的 要求。而為了達到均勻光源的要求，直下式背光模組使 用擴散板作為將光線均勻發散的重要元件。而所謂的擴 散板’就是以光線擴散為最主要之功能，利用所添加光 擴散劑種類以及折射率不同的改變，使其光線在擴散板 間反覆的折射來將光線均勻分布，藉此來達到相當不錯 的效果。但是早期的擴散效率雖然符合要求，在顯示器 朝向環保、低成本的趨勢下，已經不符合使用需求。近 年來，由於冷陰極管及電源轉換器的成本高及取得不 5 200809264 - 易’因此藉由減少燈管的使用數量及擴散元件的改 來達到符合需求及降低成本的要求。但隨著燈管的使， 數量減少，其燈管間的間隙加大，所造成的明暗不岣用 就更加嚴重，也因此有了更高擴散度的要求，而在擴^ 板中使用了大量的光擴散劑，此時冷陰極管的痕跡無、政 被擴散板所均勻化，其體擴散的行為已經無法滿足 需求，唯有改變擴散板或背光模組結構，才能兼顧高袁 度與高擴散度的需求。 ^ 'u • 另外，光擴散的效果，主要由擴散板内添加的光擴 散劑或是擴散板的表面型態來達成。因此，在擴散板的 出光面增加三角錐狀菱鏡變成為了增加光擴散效果的 種手段，但是，在擴散板上面增加一均勻的三角錐狀 菱鏡雖可以將光線重新配置來達到分光的效果，但對燈 管的遮蔽效果貢獻不大。本發明中的設計，是在於光的 出射面增加了三角狀的菱鏡結構，每組結構並對應了 燈管的位置及設計，藉由光線通過菱鏡所產生的折射 _ 或反射來改變光線前進的路徑，達成散射光線的效 果。並且可以藉由光擴散劑的添加及分布，來擴散均勻 入射光線，以符合背光模組所需的搭配需求。在傳統的 擴散板設計中，提馬擴散板的光擴散度在遮蔽燈管方面 已不足已達到很好的效果，且會降低整個背光源的亮 度，本發明中針對燈管的位置在三角錐狀的結構做不同 ’ 角度及形狀的改變，可以將光線的分佈均勻化，並藉由 添加的光擴散劑做燈管亮痕的遮避，以達到提昇均勻度 的目的。 Λ 6 200809264 本發明人有鑑於此，乃精心研究並再三測試改良， 如今終於發明出一種高均勻度之擴散板，而具有產業上 利用之價值。 【發明内容】 緣是，本發明之主要目的在於提供一種高均勻度之擴 散板，係提供一種改變光在擴散板中的行進路徑，使其從 擴散板出光面的行為改變，搭配背光模組中的光源及其它 元件，採用三角錐狀設計。將該直下式背光模組之擴散板 製造為具有複數個三角錐表面(Prism Lens)之擴散板，將一 入射光使其分光，以提高其光均句度，透過複數個三角錐 狀表面設置於該擴散板，以調整光向各方向的角度，藉此 達到光源重新配置的效果。三角錐狀菱鏡的設計也可以針 對燈管的位置及距離而定，每個依序排列的三角錐狀菱鏡 對應了冷陰極管的相鄰距離及與擴散板間的高度，以符合 三角錐狀菱鏡設計的效果；除了三角錐狀菱鏡外，板材兩 側表面同時含有適量的光擴散劑，將光線進一步分散，使 其均句化，藉此可進一步遮蔽或散射燈管的亮痕。 為了讓貴審查委員對本發明有更進一步的了 解，茲佐以圖式詳細說明本發明如下： 【實施方式】 本發明中的設計’是在於光的出射面增加了三角狀 的菱鏡結構，每組結構並對應了燈管的位置及設計’藉 由光線通過菱鏡所產生的折射或反射來改變光線前進 的路徑，達成散射光線的效果，並且可以藉由光擴散劑 的添加及分布，來擴散均勻入射光線，以符合背光模組 7 200809264 所需的搭配需求。 =第-圖及第一〜一圖所示，本發明擴散板的 出射面板材上增加三角錐狀之菱鏡結構，該菱鏡1〇係 入中、下層n、12、13 ’經由共擠押模頭將三層 ϋ结合’再經由成形滾輪成形為三角錐狀，·其令上層 11之角錐狀係為副押出機押出的部份，中層12為主 押出機押出之部份，下層13為副押出機壓出之部份。 第二圖及第二—圖所示，本發明擴散板的出 射面板材上增加梯形之菱鏡結構，該菱鏡20係包括上' 中下層2卜22、23，經由共擠押模頭將三層結構結合， 再經由成形滾輪成形為梯形；其中上層2 副押出機押出的部份，中層22為主押出機押出之部:為 下層23為副押出機壓出之部份。 勒而2第三圖及第三—圖所示，本發明擴散板的出 m 菱鐘30你上勺增杠加三角錐狀尖端呈圓弧形之菱鏡結構，該 羡鏡30一係包括上、中、下層3卜犯、犯，經由共擠押 模頭將三層結構結合’再經由成形滾輪成形為三 其中上層31之三角錐狀尖端呈圓弧形 Α係為副押出機押出的部份，中層32為主押出機押出之 4伤，下層33為副押出機壓出之部份。 射面ί:第四圖及第四〜一圖所示，本發明擴散板的出 Τ面ί材上增加圓弧狀之菱鏡結構，該菱鏡40係包括 杜i *下層4卜42、43 ’經由共擠押模頭將三層結構 ’再經由成形滾輪成形為圓弧狀；其中上層Ο之 圓弧狀係為副押出機押出的部份，中層42為主押出機 200809264 秦 押出之部份，下層43為副押出機壓出之部份。 再者，上述之菱鏡10、20、30、40結構係可以為 PMMA、MS、PS、PC…等材質，其中光擴散劑僅添加在上 層1卜2卜3卜4卜或僅添加在下層13、23、33、43， 或僅添加在中層12、22、32、42，或同時添加在上、中 層 11、12、21、22、31、32、41、42，或同時添加在中、 下層12、13、22、23、32、33、42、43，或同時添加在 上、下層 11、13、21、23、31、33、41、43，或同時添 • 加在上、中、下層 11、12、13、21、22、23、31、32、 33 、 4卜 42 、 43 〇 再者，上述之菱鏡10、20、30、40結構，其中可 再添加紫外光吸收劑，可僅添加在上層11、21、31、41， 或僅添加在下層13、23、33、43，或僅添加在中層12、 22、 32、42，或同時添加在上、中層11、12、21、22、 31、32、41、42，或同時添加在中、下層12、13、22、 23、 32、33、42、43，或同時添加在上、下層11、13、 _ 21、23、31、33、41、43，或同時添加在上、中、下層 1 卜 12、13、2卜 22、23、3卜 32、33、4卜 42、43 〇 在實際應用上，新設計的優點至少可以分以下幾個 部分來說明： 由於環保以及取得冷陰極管及電源轉換器的價格 昂貴與取得不易，新的設計可以藉由三角錐狀菱鏡來改 - 變光的重新配向，而減少冷陰極管的使用量，並可以適 :度添加光擴散劑，將光線分散達到均勻化的效果，藉此 可遮蔽因燈管間的距離加大所造成明暗不均的現象。就 9 200809264 以押出板材而言，並不會增加生產的複雜度，有易於生 產的特點。因此，新的擴散板設計具有提昇擴散板功能 與降低成本的優點。 實例 使用申請人穎台科技所生產之EML-擴散板於出光 面成型三角錐狀菱鏡，並與EMS-進行比較。三角錐狀 菱鏡間隔週期為〇.4mm，菱鏡的角度為110° ，上下表 層的厚度為（K 1mm，燈管間距離為30mm。成型後裁切成 適當形狀裝置於直下式冷陰極管背光源，進行量測，並 比較其結果。 新的設計可以藉由三角錐狀菱鏡的角度及分布的 改變來調整光向的進行，並透過調整板材表層光擴散劑 添加量的方式，新的設計在產品的變通性會比傳統產品 優良。另外一點，光擴散劑的擴散效果並不具有方向 性，是呈現不規則散射的效果，而使用三角錐狀菱鏡的 光線可以依據背光模組中燈管的距離，距離擴散板的高 度，以及燈管與反射片之間的間隙，設計成不同的結 構、形狀、及角度。在顯示器的設計上，提供了設計者 更多的空間，可以針對不同需求加以設計，提高光線的 利用率。 綜上所述，本發明高均勻度之擴散板，係一種將板 材表面成形為不同形狀之立體結構，利用板材表面不同 的立體結構及添加不同的擴散劑來達到改變光的行進 路徑，在背光模組中將冷陰極管（CCFL)所發出來的光線 200809264 ▲ * • 均勻分散，並可減少冷陰極管所使用的數量，以提供光 線從出光面出來後達到光學均勻性的效果，本發明因而 可供產業上利用，且本發明在申請前又未見於刊物或已 公開使用，實已符合專利法之規定，爰依法提出發明專 利申請。 【圖式簡單說明】 A 第一圖：係本發明菱鏡之示意圖一。 第一〜一圖：係本發明菱鏡之部份放大圖。 第二圖：係本發明菱鏡之示意圖二。 第二〜一圖：係本發明菱鏡之部份放大圖。 第三圖：係本發明菱鏡之示意圖三。 第三〜一圖：係本發明菱鏡之部份放大圖。 第四圖：係本發明菱鏡之示意圖四。 第四--圖：係本發明菱鏡之部份放大圖。 • 【主要元件符號說明】 (10、20、30、40)菱鏡 （η、2卜 31、41)上層 (12、22、32、42)中層 （13、23、33、43)下層200809264 IX. Description of the Invention: [Technical Field] The present invention relates to a diffusing plate having excellent optical diffusibility and high uniformity, and is a three-dimensional structure for forming a surface of a plate into different shapes, using different surface of the plate The three-dimensional structure and the addition of different diffusing agents to change the traveling path of the light, uniformly disperse the light emitted by the cold cathode tube (CCFL) in the backlight module, and reduce the number of cold cathode tubes used to provide light. The effect of optical uniformity Φ is achieved after coming out of the light exit surface. [Prior Art] With the popularity of digital TV, liquid crystal displays have been highly valued and highly grown in the competition of displays in recent years. In liquid crystal displays, the image is driven by the switch of the electric field, and the liquid crystal panel itself does not emit light. The backlight module is used to provide the display light source. In general, the application is a direct-lit light source on a large-sized liquid crystal display. The direct-lit backlight can be designed to achieve high brightness and uniform light source by the increase of the lamp φ and the design of the diffusing element. In order to achieve the requirement of a uniform light source, the direct-lit backlight module uses a diffuser plate as an important component for evenly diverging light. The so-called diffuser plate is the main function of light diffusion. By using the type of light diffusing agent added and the difference in refractive index, the light is evenly distributed between the diffusing plates to evenly distribute the light. Quite a good result. However, although the early diffusion efficiency meets the requirements, the display is facing environmental protection and low cost, and it has not met the needs of use. In recent years, due to the high cost of cold cathode tubes and power converters, it has been able to meet the demand and reduce costs by reducing the number of lamps used and the expansion of the diffusing components. However, as the number of lamps is reduced, the number of gaps between the lamps is increased, and the resulting shading is more serious, and thus has a higher diffusion requirement, and is used in the expansion plate. A large number of light diffusing agents, at this time, the traces of the cold cathode tube are not, the political diffusion plate is homogenized, and the body diffusion behavior can not meet the demand. Only by changing the structure of the diffusion plate or the backlight module can the high degree and the high degree High diffusion requirements. ^ 'u • In addition, the effect of light diffusion is mainly achieved by the surface type of the optical diffuser or diffuser added to the diffuser. Therefore, adding a triangular pyramid-shaped prism on the light-emitting surface of the diffuser becomes a means for increasing the light-diffusing effect, but adding a uniform triangular pyramid-shaped prism on the diffuser plate can reconfigure the light to achieve the splitting effect. However, it does not contribute much to the shielding effect of the lamp. The design of the present invention is that the exit surface of the light is increased by a triangular prism structure, and each set of structures corresponds to the position and design of the lamp, and the light is changed by the refraction _ or reflection generated by the light beam. The path of advancement achieves the effect of scattering light. Moreover, the uniform incident light can be diffused by the addition and distribution of the light diffusing agent to meet the matching requirements of the backlight module. In the traditional diffuser design, the light diffusivity of the Tamar diffuser has been insufficient to shield the lamp, and the brightness of the entire backlight is reduced. In the present invention, the position of the lamp is in the triangular cone. The shape of the structure is changed by different angles and shapes, and the distribution of light can be uniformized, and the added light diffusing agent is used as the shielding of the bright mark of the lamp to achieve the purpose of improving uniformity. Λ 6 200809264 In view of this, the inventors have carefully studied and repeatedly tested and improved, and now finally invented a diffusing plate of high uniformity, which has the value of industrial use. SUMMARY OF THE INVENTION The main purpose of the present invention is to provide a high uniformity diffusing plate, which provides a change in the traveling path of light in the diffusing plate, so that the behavior of the light emitting surface from the diffusing plate is changed, and the backlight module is matched. The light source and other components are designed with a triangular pyramid shape. The diffusing plate of the direct type backlight module is manufactured as a diffusing plate having a plurality of triangular pyramid surfaces (Prism Lens), and an incident light is split to increase the uniformity of light, and is disposed through a plurality of triangular pyramid surfaces. In the diffuser plate, the angle of the light in each direction is adjusted, thereby achieving the effect of rearrangement of the light source. The design of the triangular pyramidal mirror can also be determined according to the position and distance of the lamp tube. Each of the sequentially arranged triangular pyramidal mirrors corresponds to the adjacent distance of the cold cathode tube and the height between the diffusion plate and the triangle. The effect of the tapered prism design; in addition to the triangular pyramidal mirror, both sides of the board contain an appropriate amount of light diffusing agent to further disperse the light to make it uniform, thereby further shielding or scattering the light of the tube mark. In order to allow the reviewing committee to have a better understanding of the present invention, the present invention will be described in detail with reference to the following drawings: [Embodiment] The design of the present invention is based on the fact that the exit surface of the light is increased in a triangular shape. The structure of the lamp corresponds to the position and design of the lamp. The path of the light is changed by the refraction or reflection of the light through the prism to achieve the effect of scattering light, and can be added and distributed by the light diffusing agent. Diffusion of uniform incident light to meet the matching requirements of backlight module 7 200809264. = Fig. 1 and Fig. 1 to Fig. 1 show that a triangular pyramid-shaped prism structure is added to the exit surface plate of the diffusing plate of the present invention, and the prism is inserted into the middle and lower layers n, 12, 13 ' via coextrusion The die head combines the three layers of ' and then forms a triangular pyramid through the forming roller. The angle 11 of the upper layer 11 is the part of the sub-extruder, and the middle layer 12 is the part of the main extruder. The lower layer 13 The part that is pressed out for the sub-extension machine. 2, and 2nd, the projection surface of the diffusing plate of the present invention is added with a trapezoidal prism structure, and the prism 20 includes an upper middle and lower layer 2, 22, 23, which will be passed through a co-extruding die. The three-layer structure is combined and formed into a trapezoidal shape by a forming roller; wherein the upper layer 2 is pushed out by the sub-extruder, and the middle layer 22 is the part of the main extruder: the lower layer 23 is the portion extruded by the sub-extrusion machine. In the third and third figures of the present invention, the m-shaped bell 30 of the diffusing plate of the present invention has an arc-shaped mirror structure with a triangular tapered tip and a triangular tapered tip. The upper, middle and lower layers of the three criminals and criminals are combined with the three-layer structure through the co-extrusion die and then formed into three by the forming roller. The triangular pyramid-shaped tip of the upper layer 31 is a circular arc-shaped truss. In part, the middle layer 32 is the 4th shot of the main extruder, and the lower layer 33 is the part of the sub-press machine. The surface ί: as shown in the fourth figure and the fourth to the first figure, the curved surface of the diffusing plate of the present invention is increased in an arc-shaped prism structure, and the prism 40 includes a lower layer 4, 42 43 'The three-layer structure' is formed into a circular arc through the forming roller through the co-extruding die; wherein the arc of the upper layer is the part of the sub-extruder, and the middle layer 42 is the main extruder 200809264. In part, the lower layer 43 is the portion that is pressed out by the sub-extrusion machine. Furthermore, the above-mentioned prisms 10, 20, 30, 40 may be made of PMMA, MS, PS, PC, etc., wherein the light diffusing agent is only added to the upper layer 1 b 2 b 3 b or only added to the lower layer 13, 23, 33, 43, or only added to the middle layer 12, 22, 32, 42 or simultaneously added to the upper and middle layers 11, 12, 21, 22, 31, 32, 41, 42 or simultaneously added in the middle, The lower layer 12, 13, 22, 23, 32, 33, 42, 43 is added to the upper and lower layers 11, 13, 21, 23, 31, 33, 41, 43 at the same time, or simultaneously added to the upper, middle, Lower layer 11, 12, 13, 21, 22, 23, 31, 32, 33, 4b, 42 and 43. Further, the above-mentioned prisms 10, 20, 30, 40 have a structure in which an ultraviolet light absorber can be further added. It may be added only to the upper layer 11, 21, 31, 41, or only to the lower layer 13, 23, 33, 43, or only to the middle layer 12, 22, 32, 42 or simultaneously to the upper and middle layers 11, 12, 21, 22, 31, 32, 41, 42, or simultaneously added to the middle and lower layers 12, 13, 22, 23, 32, 33, 42, 43 or simultaneously added to the upper and lower layers 11, 13, _ 21, 23 , 31, 33, 41, 43, or at the same time In the upper, middle and lower layers 1 Bu 12, 13, 2 Bu 22, 23, 3 Bu 32, 33, 4 Bu 42, 43 In practical applications, the advantages of the new design can be explained at least in the following sections: Environmental protection and the availability of cold cathode tubes and power converters are expensive and difficult to obtain. The new design can be modified by triangular pyramidal mirrors to reduce the amount of cold cathode tubes used, and can be adapted to: The light diffusing agent is added to disperse the light to achieve a uniform effect, thereby obscuring the phenomenon of uneven brightness caused by an increase in the distance between the lamps. As far as 9 200809264 is concerned, it does not increase the complexity of production and is easy to produce. Therefore, the new diffuser design has the advantage of improving the diffuser function and reducing costs. Example An EML-diffusing plate produced by Applicant Yingtai Technology was used to form a triangular pyramidal mirror on the illuminating surface and compared with EMS-. The interval of the triangular pyramidal prism is 〇.4mm, the angle of the prism is 110°, and the thickness of the upper surface layer is (K 1mm, the distance between the lamps is 30mm. After shaping, it is cut into a suitable shape for the direct-type cold cathode tube. The backlight is measured, and the results are compared. The new design can adjust the direction of light by changing the angle and distribution of the triangular pyramidal mirror, and adjust the amount of light diffusing agent on the surface of the sheet. The design of the product will be better than the traditional product. In addition, the diffusion effect of the light diffusing agent is not directional, it is the effect of irregular scattering, and the light using the triangular pyramidal mirror can be based on the backlight module. The distance between the middle tube, the height from the diffuser, and the gap between the tube and the reflector are designed into different structures, shapes, and angles. In the design of the display, more space is provided for the designer. Designed according to different needs, improve the utilization of light. In summary, the high uniformity diffusing plate of the present invention is a kind of forming the surface of the plate into different shapes. Body structure, using different three-dimensional structure of the surface of the plate and adding different diffusing agents to change the path of light, in the backlight module, the light emitted by the cold cathode tube (CCFL) 200809264 ▲ * • is evenly dispersed, and The invention reduces the number of cold cathode tubes used to provide optical uniformity after the light exits the light exiting surface, and the invention is thus available for industrial use, and the invention has not been seen in publications or has been publicly used before application. In accordance with the provisions of the Patent Law, the invention patent application is filed according to law. [Simplified illustration] A: The first diagram is a schematic diagram of the prism of the present invention. The first to the first diagram: a partial enlarged view of the prism of the present invention. The second figure is a schematic diagram of the prism of the present invention. The second to the first drawing is a partial enlarged view of the prism of the present invention. The third drawing is the schematic diagram of the three-dimensional mirror of the present invention. A partial enlarged view of the prism of the present invention. The fourth figure is a schematic diagram of the fourth embodiment of the present invention. The fourth--picture is a partial enlarged view of the prism of the present invention. 20 30, 40) of the prism (η, 2 BU 31, 41) the upper layer (12,22,32,42) middle layer (13,23,33,43) lower