200923433 九、發明說明： 【發明所屬之技術領域】 本發明涉及一種背光模組及其稜鏡片，尤其涉及一種 用於液晶顯示之背光模組及其稜鏡片。 【先前技術】 請參見圖1 ’所示為一種習知直下式背光模組1〇〇， 其包括框架11、設置在框架u内部之複數光源12、依次 設置在光源12上方並蓋住框架u之一擴散板13及一稜鏡 片1〇。其中擴散板13内一般含有用以擴散光線之散射粒 子。稜鏡片ίο包括透明基板101、形成於透明基板1〇1上 之透鏡層103。透鏡層103上具有複數長條形v型凸起 105。該透鏡層1〇3 一般是通過在透明基板1〇1上塗佈紫外 線固化樹脂並加以光照固化形成。 使用時，由複數光源12產生之光線進入擴散板13被 均勻擴散後，其繼續進入稜鏡片1〇，在稜鏡片1〇之長條 乂 1凸起105之作用下使出射光線發生一定程度之聚 集，從而提高背光模組100在特定視角範圍内之亮度。 請一併參閱圖2與圖3,光線在經擴散板13擴散後變 得均勻’但也使散射後之光線入射稜鏡片10之角度變得較 為雜亂。此雜亂光線進入稜鏡片1〇後於v型凸起】的介 面出射’部分出射光線(如al、a2)會沿靠近豎直之方向(即 ^且ιϋ相平仃之方向）聚集’此部分出射光線可提升背光 nr之正面出射亮度，·但是，有部分出射光線（如$ a、型凸起105介面朝靠近水平方向（X軸方向）出射， 6 200923433 此部分出射光線未能有效利用；另外，仍有部分光 a5、a6)於:型凸起105介面發生折射後又重新進入稜鏡片 ’此過程光能損失較大。此外，稜鏡片1〇之複數 凸起奶間平行排佈，其對光線之聚集仙主 v型凸起谢之延伸方向相垂直之平面，·而對與v型凸起 伸方向相平行之平面之光線無聚集作用’使該部 分光線未能有效利用。 【發明内容】 鐾於上述狀況，有必要提供一種可提高光線有效利用 率、出光亮度高之背光模組及其稜鏡片。 -種稜鏡片’該稜鏡片由一透明本體構成，該透明 本體包括第一表面及與該第一表面相對之第二表面。該 透明本體之第一表面具有複數微凹槽，每一微凹槽包括 四依次連接之内側面’每一内側面之水平寬度自該第一 表面向内逐漸減小，該透明本體之第二表面具有複數長 條狀圓弧形凸起。 一種背光模組，其包括光源、擴散板及稜鏡片，該 擴散板及棱鏡片依次設於該光源之上方，該稜鏡片由一 透明本體構成，該透明本體包括第—表面及與該第一表 面相對之第二表面。該透明本體之卜表面具有複數微 凹槽，每一微凹槽包括四依次連接之内側面，每一内側 面之水平I度自該第一表面向内逐漸減小，該透明本體 之第二表面具有複數長條狀圓弧形凸起。 上述稜鏡片之第一表面具有複數微凹槽、第二表面具 200923433 有複數長條狀圓弧形凸起，由於該稜鏡片第一表面上之 複數微凹槽具有傾斜表面結構，第二表面之複數長條狀 圓弧形凸起具有變化之曲面結構，該變化之曲面結構與 傾斜表面結構相配合而協同作用於入射該稜鏡片之光 線，因此可使使用該稜鏡片之背光模組提高出射光亮度 以及更有效之利用光線。 【實施方式】 下面將結合附圖及實施例對本發明之背光模組及其 棱鏡片作進一步之詳細說明。 明參閱圖4，所示為本發明較佳實施例一之背光模組 200 ’其包括稜鏡片2〇和依次設置於稜鏡片2〇 一側之擴 政板23、複數光源22及用於容納複數光源之框架2工， 稜鏡片20與擴散板23蓋住框架21，光源22發出之光線 直接或藉由框架21之反射進人擴散板23，於擴散板23 擴散後進入稜鏡片20進行聚集。 請參閱圖5與圖6,稜鏡片2〇由一透明本體構成， ，透明本體包括第-表面謝及與第—表面2〇ι相對之 第一表面203。第一表面201具有複數微凹槽，第二 表面203具有複數長條狀圓弧形凸起204。 ^再參閱圖4與圖5,第-表面2〇1面向擴散板Μ， /、上之微凹槽202用於收敛射入稜鏡# 2〇之光線 微凹槽2〇2呈規則陣列緊密排佈，且微凹槽202之陣列 ^方向與稜鏡片側邊之夾角為直角。每—微凹槽皿 已括四相互逹接之内側面，即微凹槽如為四稜錐形。 8 200923433 微凹槽202之内側面為兩兩相對之四等腰三角形，其中 一兩相對之等腰二角形之間之夾角與另一兩相對之等腰 角开/之間之失角可以不同，但最好都在度至度 :範圍内。」目鄰微凹槽2〇2之中心間距p滿足以下關係 L 0.025笔米犯！宅米。藉由調整該夹角之角度及微凹 之長寬比，可調整稜鏡片20之增光率及出光視角。 請再參閱圖4與圖6，第二表面2〇3背向擴散板… 二之長條狀圓弧形凸起2〇4用於使從棱鏡片出射之 線發生聚集作用。複數長條狀圓弧形凸起2G4呈規則 陣列緊密排饰。相鄰長條狀圓孤形凸起204 <中心間距 足-下關係式·· 0·025毫米邮·5毫米。圓孤形凸 204在垂直方向橫截面為扇形面，該扇形面所在圓之 2=之=:下關係式：啊 2〇4之取大南度η滿足以下關係式：〇〇1毫米〈⑽；即 當相鄰圓弧形凸起204之中心間距匕為〇 〇25毫米至Η ，米時，每一圓弧形凸# 204垂直方向橫截 為⑽毫来至3毫米，每一圓弧形凸起2〇4之 取大南度Η可為0.01毫米至圓弧形凸起2〇4垂直方向 截面所在圓之半徑。本實施例中，圓弧形凸起謝之言、 度Η為圓弧形凸起2〇4之垂直方向横截面半圓之半徑^ 相鄰圓弧形凸起2〇4之中心間距&等於圓弧形凸起咖 垂直方向橫截面半圓之直徑。 稜鏡片20之總體厚度可為〇 5毫米至3毫米。 片20可由聚甲基丙烯酸甲醋、聚碳酸醋、聚苯“ 200923433 乙稀-曱基丙烯酸曱醋共聚物中之一種或一種以上之材料 注塑成型而成。製備過程中需於模具上設置與長條狀圓 弧开> 凸起204相應之凹陷結構以及微凹槽202相靡之凸 起結構’以便使稜鏡片20可於單次注塑過程中成型。 框架21可由具有向反射率之金屬或塑膠製成，或塗 佈有高反射率塗層之金屬或塑膠製成。 光源22可為線光源或點光源，例如發光二極體與冷 陰極螢光燈。 … 由於稜鏡片20之第一表面201上之複數微凹槽2〇2 具有傾斜表面結構，第二表面203之複數長條狀圓弧形 凸起204具有變化之曲面結構，該變化之曲面結構與傾 斜表面結構相配合而協同作用於入射稜鏡片2〇之光線，' 因此易於使使用稜鏡片20之背光模組2〇〇提高出射光亮 度以及更有效之利用光線。 具體於本實施例中，當光線從第一表面201進入稜鏡 片20時，由於第一表面2〇1存在複數微凹槽，微凹 槽202傾斜之表面結構使得光線向垂直於稜鏡片2〇之方 向（即Y方向）發生一定程度之收斂；當光線從第二表 面203出射時’由於第二表φ 2()3存在複數長條狀圓弧 形凸起204’長條狀圓弧形凸起2〇4變化之曲面結構使得 出射，線向垂直於稜鏡片2G之方向進—步聚集，從而可 較大程度之提高背光模組200之出光亮度。與此同時， 由於第表面201在光線進入稜鏡片2〇時，將大部分光 線收斂至靠近垂直於稜鏡片20之方向，故當光線從第二 200923433 表面202出射時，與稜鏡片2〇相平行方向出射之光線較 少，從而減少了再次返回棱鏡片2〇之光線而使更多之光 線被有效利用。 另外，本發明之稜鏡片20是採用注塑成型之方式一 體成型’而傳統之稜鏡片是採用於透明板上塗佈料線 固化樹脂並加以光照固化形成，兩者相較，種鏡片更 易實現快速量產及降低成本；而且在使用時，種鏡片2〇 内不存在光線介面損失，具有更高之光線利用率。此外， 傳統方法在透明板上塗覆樹脂膜形成微結構，由於塗覆 之樹脂膜與透明板結合力—般較低且樹脂膜本身難以形 成而強度’因此容易導致料έ士錯·扯立,丨# 令勿命欽微总構被刮傷、壓損；而 明採用注塑成财Μ稜鏡片2G —體成型之長條狀㈣ 形凸起2〇4以及微凹# 202則相應具有較高之結構強 度，可避免或減少在使用中被損壞之危險。 JT以理解，第二表面203也可用於面向擴散板u，而 使第一表面201背向擴散板23。 請參閱圖7,所示為本發明較佳實施例：之 30。棱鏡片30與實施例一之棱鏡片2〇相似，其. 於：第-表面3CU之微凹槽地為四稜台形凹槽，= 凹槽302之間有間隙。 做 可以理解’上述稜鏡片中，微 稜鏡片側邊之炎角還可為銳角槽之陣列排佈方向與 综上所述，本發明符合發明專利要件，麦依法提出專 申請。惟，以上所述者僅為本發明之較佳實施例，本發明之 11 200923433 =並W上述h方式為限，舉凡熟悉本案 ==發:_作之等效修錦或變化，皆應涵蓋於 以下之申凊專利範圍内。 【圖式簡單說明j 圖1係一種習知背光模組之剖面示意圖。 圖2係圖1所示背光模組之稜鏡片之立體圖。 圖3係圖2所示棱鏡片沿m_nU|j帛之光 圖。 圖 圖4係本發明較佳實施例一之背光模組之剖面示意 圖5係圖4所示背光模組之稜鏡片之立體圖。 圖6係圖4所示背光模組之稜鏡片之另—視角立體圖。 圖7係本發明較佳實施例二之稜鏡片之仰視圖。 【主要元件符號說明】 (本發明） 背光模組 200 稜鏡片 20 、 30 、 40 、 50 第一表面 201 ' 301 微凹槽 202 、 302 第二表面 203 長條狀圓弧形凸起 204 擴散板 21 光源 22 框架 23 12 200923433 背光模組 100 棱鏡片 10 入光面 101 出光面 103 V型凸起 105 框架 11 光源 12 擴散板 13 13BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a backlight module and a cymbal thereof, and more particularly to a backlight module for a liquid crystal display and a cymbal thereof. [Prior Art] Referring to FIG. 1 ' is a conventional direct type backlight module 1A, comprising a frame 11, a plurality of light sources 12 disposed inside the frame u, sequentially disposed above the light source 12 and covering the frame u One of the diffusion plates 13 and one of the cymbals 1 〇. The diffusion plate 13 generally contains scattering particles for diffusing light. The wafer ίο includes a transparent substrate 101 and a lens layer 103 formed on the transparent substrate 1〇1. The lens layer 103 has a plurality of elongated v-shaped projections 105 thereon. The lens layer 1〇3 is generally formed by coating an ultraviolet curable resin on a transparent substrate 1〇1 and curing it by light. In use, after the light generated by the complex light source 12 is uniformly diffused into the diffusion plate 13, it continues to enter the cymbal 1 〇, and the emitted light is caused to a certain extent by the action of the long 乂1 protrusion 105 of the cymbal 1〇. Gathering, thereby increasing the brightness of the backlight module 100 over a specific viewing angle range. Referring to Figures 2 and 3 together, the light becomes uniform after being diffused through the diffusion plate 13 but also causes the angle of the scattered light to enter the crotch panel 10 to become messy. This messy light enters the cymbal 1 〇 and then emerges from the interface of the v-shaped bulge. 'Partially emitted rays (such as al, a2) will gather in the direction close to the vertical (ie, the direction of the ϋ ϋ ϋ ') The outgoing light can enhance the front exit brightness of the backlight nr, but some of the emitted light (such as $ a, the type of convex 105 interface is emitted toward the horizontal direction (X-axis direction), 6 200923433 this part of the emitted light is not effectively utilized; In addition, some of the light a5, a6) is refraction after the surface of the protrusion 105 is refraction and then re-enters the slab. In addition, the plurality of raised milks of the cymbal sheet are arranged in parallel, and the plane of the light is concentrated on the plane perpendicular to the direction in which the v-shaped protrusion extends, and the plane parallel to the direction in which the v-shaped protrusion extends The light has no aggregation effect', so that part of the light is not effectively utilized. SUMMARY OF THE INVENTION In view of the above circumstances, it is necessary to provide a backlight module and a chip which can improve the effective utilization rate of light and high brightness. - 稜鏡片' The cymbal is composed of a transparent body comprising a first surface and a second surface opposite the first surface. The first surface of the transparent body has a plurality of micro-grooves, each of the micro-grooves includes four inner sides of the sequentially connected ones. The horizontal width of each inner side gradually decreases inward from the first surface, and the transparent body is second. The surface has a plurality of elongated arc-shaped projections. A backlight module includes a light source, a diffusing plate and a cymbal plate. The diffusing plate and the prism sheet are sequentially disposed above the light source. The cymbal piece is composed of a transparent body, and the transparent body includes a first surface and the first The surface is opposite the second surface. The surface of the transparent body has a plurality of micro-grooves, each micro-groove includes four inner sides connected in sequence, and the horizontal I degree of each inner side gradually decreases inward from the first surface, and the transparent body is second. The surface has a plurality of elongated arc-shaped projections. The first surface of the cymbal has a plurality of micro-grooves, and the second surface has a plurality of elongated arc-shaped protrusions of 200923433, wherein the plurality of micro-grooves on the first surface of the cymbal have an inclined surface structure, and the second surface The plurality of long arc-shaped protrusions have a varying curved surface structure, and the changed curved surface structure cooperates with the inclined surface structure to cooperate with the light incident on the cymbal, thereby improving the backlight module using the cymbal Brightness of light and more efficient use of light. [Embodiment] Hereinafter, a backlight module and a prism sheet thereof according to the present invention will be further described in detail with reference to the accompanying drawings and embodiments. Referring to FIG. 4, there is shown a backlight module 200 of a preferred embodiment of the present invention, which includes a cymbal cymbal 2 and a expansion board 23 disposed on one side of the cymbal 2 、, a plurality of light sources 22, and a housing The frame of the plurality of light sources is covered, and the cymbal 20 and the diffuser plate 23 cover the frame 21. The light emitted by the light source 22 enters the diffuser plate 23 directly or through the reflection of the frame 21, and diffuses into the cymbal plate 20 after being diffused by the diffuser plate 23 for aggregation. . Referring to Figures 5 and 6, the cymbal sheet 2 is formed of a transparent body including a first surface and a first surface 203 opposite the first surface. The first surface 201 has a plurality of micro-grooves, and the second surface 203 has a plurality of elongated arc-shaped projections 204. Referring again to FIG. 4 and FIG. 5, the first surface 2〇1 faces the diffusion plate Μ, and the upper micro groove 202 is used to converge the light 微# 2〇 light micro groove 2〇2 in a regular array tight Arranged, and the angle between the array direction of the micro-grooves 202 and the sides of the cymbals is a right angle. Each of the micro-flushing vessels has four inner sides that are spliced to each other, that is, the micro-grooves are quadrangular pyramids. 8 200923433 The inner side of the micro-groove 202 is a pair of four isosceles triangles, and the angle between one or two opposite isosceles triangles and the other two opposite isosceles angles may be different. , but it's best to be in the degree: to the extent. The center-pitch p of the adjacent micro-groove 2〇2 satisfies the following relationship L 0.025 pens! House rice. The brightness enhancement and the viewing angle of the cymbal 20 can be adjusted by adjusting the angle of the included angle and the aspect ratio of the dimples. Referring to Fig. 4 and Fig. 6, the second surface 2〇3 faces away from the diffusing plate... The long strip-shaped arcuate projection 2〇4 is used for aggregating the line emerging from the prism sheet. The plurality of long circular arc-shaped projections 2G4 are arranged in a regular array. Adjacent strip-shaped rounded solitary protrusions 204 < center spacing foot-down relationship · · · · · · · · · · · · · · · · · · The circular orphan convex 204 has a fan-shaped surface in the vertical direction, and the circular shape of the circular surface is 2==: The following relationship: ah 2〇4 takes the south degree η to satisfy the following relationship: 〇〇1 mm<(10) That is, when the center-to-center spacing 相邻 of the adjacent arc-shaped protrusions 204 is 〇〇25 mm to Η, m, each arc-shaped convex #204 has a vertical cross-section of (10) millimeters to 3 mm, each arc The shape of the protrusion 2〇4 can be from 0.01 mm to the radius of the circle in which the arc-shaped protrusion 2〇4 is perpendicular to the cross section. In this embodiment, the circular arc-shaped convex Xie said, the degree is the radius of the circular cross-section semicircle of the arc-shaped convex protrusion 2〇4 ^ The center-to-center spacing of the adjacent circular arc-shaped convex protrusion 2〇4 is equal to the circular arc The shape of the semi-circle of the cross-section of the convex coffee in the vertical direction. The overall thickness of the cymbal sheet 20 can be from 5 mm to 3 mm. The sheet 20 may be injection-molded from one or more materials of polymethyl methacrylate, polycarbonate, and polyphenyl "200923433 ethylene-mercapto acrylate vinegar copolymer. The preparation process needs to be set on the mold. The elongated arc-shaped opening > the corresponding recessed structure of the protrusion 204 and the raised structure of the micro-groove 202 are formed so that the cymbal sheet 20 can be formed in a single injection molding process. The frame 21 can be made of metal having a reflectivity Or made of plastic or metal or plastic coated with a high reflectivity coating. The light source 22 can be a line source or a point source, such as a light emitting diode and a cold cathode fluorescent lamp. The plurality of micro-grooves 2〇2 on a surface 201 has an inclined surface structure, and the plurality of elongated arc-shaped protrusions 204 of the second surface 203 have a varying curved surface structure, and the curved surface structure cooperates with the inclined surface structure Synergistically acting on the light incident on the cymbal 2 ', 'so it is easy to use the backlight module 2 of the cymbal 20 to improve the brightness of the emitted light and more effectively utilize the light. Specifically, in this embodiment, when the light is from the first When the surface 201 enters the cymbal 20, since the first surface 2〇1 has a plurality of micro-grooves, the surface structure of the micro-grooves 202 is inclined such that the light converges to a certain extent in a direction perpendicular to the cymbal 2〇 (ie, the Y direction). When the light is emitted from the second surface 203, 'there is a plurality of long circular arc-shaped protrusions 204' due to the second table φ 2 () 3, and the curved surface structure of the long circular arc-shaped protrusions 2 〇 4 causes the exit, The line is stepped up in a direction perpendicular to the cymbal 2G, so that the brightness of the backlight module 200 can be increased to a large extent. At the same time, since the first surface 201 enters the cymbal 2 光线, most of the light is transmitted. Converging to a direction perpendicular to the cymbal 20, when the light exits from the surface 02 of the second 200923433, less light is emitted in parallel with the cymbal 2 ,, thereby reducing the light returning to the prism sheet 2 again. Further, the light is effectively utilized. In addition, the cymbal sheet 20 of the present invention is integrally molded by injection molding, and the conventional enamel sheet is coated with a curing resin on a transparent plate and cured by light. Compared with the two, the lens is easier to achieve rapid mass production and lower cost; and when used, there is no light interface loss in the lens 2, which has higher light utilization rate. In addition, the traditional method is coated on the transparent plate. The resin film is formed into a microstructure, and the bonding force between the coated resin film and the transparent plate is generally low and the resin film itself is difficult to form and the strength is so easy to cause the material to be misplaced and erected, 丨# The structure is scratched and pressure-damped; and the long strip-shaped (four) shaped protrusions 2〇4 and dimples #202 which are injection molded into the financial sheet 2G have a higher structural strength and can be avoided or reduced. The risk of being damaged in use JT understands that the second surface 203 can also be used to face the diffuser plate u with the first surface 201 facing away from the diffuser plate 23. Referring to Figure 7, there is shown a preferred embodiment of the present invention: The prism sheet 30 is similar to the prism sheet 2 of the first embodiment, wherein: the micro-groove of the first surface 3CU is a quadrangular truncated groove, and there is a gap between the grooves 302. It can be understood that in the above-mentioned cymbal, the inflammatory angle on the side of the micro cymbal may also be an array arrangement direction of the acute angle groove and the above-mentioned arrangement, and the present invention complies with the invention patent requirement, and the mai has filed a special application. However, the above description is only a preferred embodiment of the present invention, and 11 200923433 of the present invention is limited to the above-mentioned h mode, and all equivalents of the case == hair: _ for equivalent repair or change should be covered. Within the scope of the following claims. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic cross-sectional view of a conventional backlight module. 2 is a perspective view of a cymbal of the backlight module shown in FIG. 1. Fig. 3 is a light diagram of the prism sheet shown in Fig. 2 along m_nU|j帛. FIG. 4 is a cross-sectional view of a backlight module according to a preferred embodiment of the present invention. FIG. 5 is a perspective view of a cymbal of the backlight module of FIG. FIG. 6 is another perspective view of the cymbal of the backlight module shown in FIG. 4. FIG. Figure 7 is a bottom plan view of a cymbal according to a preferred embodiment of the present invention. [Main component symbol description] (Invention) Backlight module 200 cymbal 20, 30, 40, 50 First surface 201' 301 Micro groove 202, 302 Second surface 203 Long arc-shaped protrusion 204 Diffusion plate 21 Light source 22 Frame 23 12 200923433 Backlight module 100 Prism sheet 10 Light-incident surface 101 Light-emitting surface 103 V-shaped projection 105 Frame 11 Light source 12 Diffusion plate 13 13