1271584 ___ 办年/1月e日修(更)正替換頁 九、發明說明 【發明所屬之技術領域】 本發明是有關^ -種背光模組’特別是—種使用於背光 模組之延壓式光學板材。 【先前技術】 背光模組（Backlight module)係泛指可提供產品一個 背面光源的組件，目前運用在各種資訊、通訊、消費產品上， 如：液晶顯示器（Liquid Crystal Display，LCD )、底片掃 描器、幻燈片看片箱等產品。 一般而言背光模組主要是由三個部分所組成：外殼、光 學板材及光源。依照其光源入射位置的不同，可分成側光式 入光（edge lighting)與直下式入光（bottom lighting)兩種。 側光式入光之背光模組，通常是應用於例如手提型電腦 等要求省電與輕薄之產品上。為了達到輕薄之要求，通常是 於背光模組的側邊放置光源，並藉由導光板（Light guide plate)，將光源出射的光導引至顯示面板上。導光板係利用 射出成型的方法將甲基丙婦酸甲醋聚合物（Poly methyl methacrylate， PMMA)壓製成表面光滑的板塊，然後在導 光板的底面用具有光擴散之材料進行網版印刷，或直接以射 出成型方式產生擴散點，以破壞光的全反射使光折射出導光 板表面，再利用點的疏密或大小，使出射的光達到初步均化 的效果。 5 1271584 _ 缸年么月β日修漫)正替換頁 習知技術係於顯示面板與光源間設置複數個光學膜 片’如擴散膜片（Diffuser film)或稜鏡片（Prism讣州）等。第 1圖係繪示習知之側光式背光模組的概略剖視圖。側光式背 光模組1〇〇係由外殼η、導光板12、反射膜片14、至少一 片棱鏡片19、複數個光源16以及擴散膜片is所組成。稜 鏡片係藉由光線的折射以改變光線出射角度，進而增加 正視角之輝度。擴散板的主要功能則是將出射光線做散射 處理修正原始光源視角分布，以消除光源的亮帶與陰影， 進而使畫面的輝度更均勻，達到霧化的效果。 直下式入光之背光模組，通常是應用於例如電視等需具 備高亮度之產品上。為了提昇輝度，傳統上是將複數個光源 排列於顯示面板之正下方，使得光源的輪廓極易顯示於畫面 上，造成整體畫面之輝度不均勻。 為了解決上述問題，習知技術係於顯示面板與光源間設 置擴散板與複數個光學膜片，如擴散膜片（Diffuser film)、 稜鏡片（Prism sheet)。第2圖係繪示習知之直下式背光模組 的概略剖視圖。直下式背光模組200係由外殼21、反射板 24、複數個光源26、稜鏡片29、以及擴散板28所組成。 然而，側邊入光式背光模組的導光板，使用網版印刷製 作易產生印刷不均勻的現象，若使用射出成型製作則需要另 外開模，成本較高；再者，側邊入光式背光模組中擴散膜片 與稜鏡片的設置，不僅增加材料與組裝成本，亦浪費膜片之 置入空間。而直下式背光模組中擴散板之製作，係以透明板 材添加擴散劑的方式製作，雖然擴散劑可產生光的散射效 果，但卻會吸收光而降低光使用效率。 1271584 因此有必要提供一 組，可兼顧光使用效率、 泠年Θ月/3日修决)正替換頁 種具有改良式光學板材的背光模 光均勻度以及材料與組裝之成本。 【發明内容】 因此本發明的目的就是在提供一種兼顧光均句度以及 材料與組裝成本之背光模組。 本發明之技術特徵在於利用機械壓印方式製造複合式 光學板材，以取代傳統板材需再額外附加光學膜片之結構， 進而產生均勻的面光源。 藉由本發明，不僅可以減少光學薄膜片的使用，以減少 對光源的吸收，提高背光膜組的光使用效率。而且，能夠簡 化背光模組之組裝製程。 因此本發明不僅兼顧光使用效率以增加液晶螢幕顯示 器之亮度，並且能夠大幅降低背光膜組之材料與組裝成本， 並且符合薄型化的產業需求。 【實施方式】 · 請參照第3圖，第3圖係根據本發明的第一實施例所繪 示之側光式背光模組的概略剖視圖。 第3圖所繪示之側光式背光模組300結構與第1圖之背 光模組100結構相似，最大的不同點在於兩種背光模組所採 用的光學板材、膜片以及其製造方式。本實施例之背光模組 300結構係由外殼31、光學板材33、反射片34、背光源36 所組成。 7 1271584 #年^月β日修瘦)正替換頁 外殼3 1係一密閉結構，包括一光出射開口 35，外殼3 i 之材質包括塑化材料、金屬材料、或其他不透光材質。主要 力月b在支持貪光模組並防止光線從光出射開口 3 5以外部分 漏。 反射片34，位於背光模組之最内層，為一層具高反射 性之光學膜片，或直接在背光模組300之外殼底部31上塗 佈高反射材質（例如：白漆）。 光學板材33位於反射片34與光出射開口 35之間，係 為一光源傳播介質依據背光模組之設計，光學板材33可以 為具有不同形狀之結構，例如楔型結構、或立方體結構，厚 度範圍在4.0mm到12mm之間。在本發明的第二實施例之 中’光學板材3 3係採用厚度大約1 Qmm之立方體結構。 光學板材33的形成，係使用一延壓製程，將至少兩 種材質加以共同延壓成型。在本發明的第一實施例之 中’光學板材3 3係使用塑膠壓板技術將一聚碳酸醋樹脂 材質層33a以及一甲基丙烯酸甲酯聚合物層331)共同延壓 成型的雙層結構。在本發明的另一些實施例之中，光學板 材可以是多種材質共同延壓成型的多層結構。其中光學板材 33的材質可以是，例如高透光之甲基丙烯酸甲酯聚合物的 均聚物或共聚物、其他軟性光學膜片（例如，擴散板、透明 膜片）、聚碳酸酯樹脂或MMA/苯乙烯共聚物等。 光學板材33具有兩個延壓表面，其中至少一延壓表面 具有延壓立體圖案33a’，此一延壓立體圖案33a，係在光學 板材壓出成型時’將預先刻劃於延壓滾輪上之延壓立體 1271584 铃年/工月/3日修(受)正替換頁 圖案，以壓印的方式轉印至延壓表面之上。延壓立體圖 案3 3a’的設計係配合不同光學目的，例如，配合背光源 36之排列、凝聚光線增加輝度或配合出射光散射狀況加以 調整。在本發明的一些實施例之中，延壓立體圖案33a，之 截面形態，可以是對稱或不對稱、規則或不規則之波浪 狀、鋸齒狀、方形齒波狀或其他合適之圖案。在本發明之第 一實施例之中，延壓立體圖案33a’係在聚碳酸酯樹脂材質 層3 3a上轉印一稜鏡結構，用以取代傳統背光模組需外 加棱鏡片之結構，使光線經過立體圖案33a，的折射作用 之後使光線向上集中。 請參照第4圖，第4圖係根據本發明的第二實施例所繪 示之側光式背光模組的概略剖視圖。 第4圖所繪示之侧光式背光模組4〇〇結構係由外殼41、光 學板材43、反射片44、背光源46所組成。與第3圖之背光 模組300結構相似，主要不同點在於：光學板材43之兩側 分別具有延壓立體圖案43a，、43b，，而第3圖所繪示之光學 板材33僅有一側具有延壓立體圖案33a，。 光學板材43位於反射片44與光出射開口 45之間，係 為一光源傳播介質。依據背光模組之設計，光學板材43可 為具有不同型體之結構，例如楔型或立方體結構，厚度範圍 在4.0mm到12mm之間。在本發明的第二實施例之中，光 學板材43係採用厚度大約1 〇mm之立方體結構。 光學板材43的形成，係使用一延壓製程，將至少一 種材質加以延壓成型。在本發明的第二實施例之中光學 板材43是兩種材質共同延壓成型的雙層結構。在本發明的 1271584 —_ 齡崎3日修⑻正替換頁 另-些實施例之中，光學板材可以是多種材質共同延壓成型 的多層結構。其中光學板材43的材質可以是，例如高透光 之甲基丙烯酸甲酯聚合物的均聚物或共聚物、其他軟性光學 ，Μ例如’擴散板、透明膜片）、聚碳酸醋樹脂、匪A/ 本乙烯共聚物、或其他透光之塑化材質。在本發明的第二 實施例之中，光學板材43係使用塑膠壓板技術將一聚碳 酸酯樹脂材質43a以及一曱基丙烯酸甲酯聚合物43b共壓 成型的雙層結構。 在本發明之第二實施例之中，延壓立體圖案43a，係在 甲基丙烯酸甲酯聚合物43a上轉印一規則之鋸齒狀稜鏡 圖案，用以取代傳統之棱鏡片，使光線經過立體圖案43 a， 的折射作用之後凝聚光線增加輝度。延壓立體圖案43b， 係在聚碳酸酯樹脂材質層4 3 b上轉印一不規則之網狀凸 點用以取代傳統導光板之印刷網點與射出成型網點，用 以破壞光線之全反射使光線传以穿出聚碳酸酯樹脂材質 層4 3 b ’並藉由延壓立體圖案43b’的疏密排列以形成均 勻化的面光源。 請參照第5圖’第5圖係根據本發明的第三實施例所繚 示之直下式背光模組的概略剖視圖。 第5圖所繪示之背光模組500結構與第2圖之背光模組200 結構相似，最大的不同點在於兩種背光模組所採用的光學板 材以及其製造方式。本實施例之背光模組50結構係由外殼 51、光學板材53、反射片54、背光源56所組成。 光學板材53位於反射片54與光出射開口 55之間，係 為一光源傳播介質依據背光模組之設計，光學板材53可為 1271584 ___ 丄月β日修(臭)正替換頁 f有不同型體之結構’例如楔型結構、或立方體結ϋ 純圍在1.5mm到4mm之間。在本發明的第三實施例之中， 光學板材53係採用厚度大約2mm之立方體結構。 光干板材53的形成，係使用一延壓製程，將至少兩 種=質加以共同延壓成型。在本發明的第三實施例之中 光學板材53是兩種材質共同延壓成型的雙層結構。在本發 明的另-些實施例之中，光學板材可以是多種材質共同延壓 成型的多層結構。其中，光學板材53的材質可以是，例如 南透光之甲基丙烯酸甲醋聚合物的均聚物或共聚物其他軟 性光學膜片（例如’擴散板、透明膜片）、聚碳酸酯樹脂、 MMA/苯乙烯共聚物。在本發明的第三實施例之中，光學 板材53係使用塑膠壓板技術將一聚碳酸酯樹脂材質層 53a以及一甲基丙烯酸甲酯聚合物層53b共同延壓成型的 雙層結構。 在本發明之第三實施例之中，延壓立體圖案53a，係在 聚碳酸酯樹脂材質層53a上轉印一規則之鋸齒狀稜鏡圖 案，用以取代傳統之稜鏡片，使光線經過立體圖案5 3 a， 的折射作用之後凝聚光線增加輝度。53b則為一甲基丙烯 酸甲酯聚合物擴散層，光線透過擴散層的散射處理可達到霧 化的效果。 凊參照第6圖’第6圖係根據本發明的第四實施例所繪 示之直下式背液晶顯示裝置的概略剖視圖。 第6圖所繪示之液晶顯示裴置600係採用一液晶顯示面 板6G，與第5圖所繪示之直下式背光模組500組合而成。 1271584 荩伊月/3日修(動正替換頁 在本實施例之中，背光模組500結構係由外殼51、光學板 材53、反射片54、背光源56所組成。光學板材53係採用 塑膠壓板技術將一聚碳酸酯樹脂材質53a以及一 f基丙 烯酸甲酯聚合物53b共壓成型之雙層立方體結構，厚度大 約2 mm。光學板材53之延壓表面具有一延壓立體圖案 5 3 a ’係在聚碳酸g旨樹脂材質層5 3 a上轉印一不規則之 光學圖案，使光線經過立體圖案53a，的折射作用凝聚光 線增加輝度。53b則為一擴散層，光線透過擴散層的散射 處理可達到霧化的效果。背光源56則採用冷陰極螢光燈管 之直下式光源。 根據以上所述之較佳實施例，本發明可以藉由機械延壓 成形的方式將兩種以上之塑化材質共同延壓形成光學板 材’並同時於光學板材之表面形成立體圖案，用以減少或取 代光學薄膜片的使用以降低光吸收量，藉以提高光使用效率 增加背光膜組的輝度，並且達到消除背光源所生成的亮帶與 陰影的效果；而且，可以拉近背光源與入光基板之間的距 離，縮短背光膜阻的厚度。因此本發明不僅可減少背光模組 的成本、簡化背光模組之組裝製程，並且能夠符合背光模組 薄型化的需求。 透過以上所述之實施例，讀者當可以明白本發明之技術 特徵與優勢。然而，以上所述之實施例僅用於說明本發明之 技術内容，並非用以限制本發明的範圍。例如，本發明係使 用機械將兩種以上之塑化材質共同延壓成形以製造光學板 材’並形成光學板材之立體圖案，藉以取代傳統之光學膜 12 1271584 你年P月/3日修(更)正替換頁 片，產生散射均勻之可見光，消除背光源所生成的亮帶與陰 影’並縮短光傳播介質的厚度。然而，上述實施例僅提供較 佳之案例，立體圖案之設計必須配合出射光之散射狀況、輝 度需求以及光源之配置加以更動，才能達到不同之光學目 的。加上，光學膜片材質的選擇也會影響光散射程度以及光 擴散之距離。因此，本發明之實施例所述之操作條件並不能 做為發明範圍之限制，所有的操作條件均必須視所使用光源 之波長、光散射均勻程度以及光利用率來作為調整的依據。 雖然本發明已以較佳實施例揭露如上，然而任何熟習此 _ 技藝者’在不脫離本發明之精神和範圍内，當可作各種之更 動與潤飾，因此本發明之保護範圍當視後附之申請專利範圍 所界定者為準。 【圖式簡單說明】 為了更完整了解以上所述之本發明的内容以及技術優 勢’請參考上述之說明施並配合隨文附錄之圖示。必須強調 的是，根據產業之標準操作模式，不同的附圖形均未按照比 修 例尺繪圖。事實上為了清楚地說明，不同的附圖都有可能被 任意地擴大或縮小。圖示說明如下： 第1圖係繪示習知之側光式背光模組的概略剖視圖。 第2圖係繪示習知之直下式背光模組的概略剖視圖。 第3圖係根據本發明的第一實施例所繪示之側光式背 光模組的概略剖視圖。 第4圖係根據本發明的第二實施例所繪示之側光式背 13 1271584 月β日修(愛)正替換頁 光模組的概略剖視圖。 第5圖係根據本發明的第二實施例所緣示之直下式背 光模組的概略剖視圖。 第6圖係根據本發明的第四實施例所綠示之直下式背 液晶顯示裝置的概略剖視圖。 【主要元件符號說明】 100、200、3 00、400、5 00 :背光模組 11、 2 1、3 1、41、5 1 :外殼 # 12、 22 ·導光板 14、24、34、44、54:反射片 16、26、36、46、56 :背光源 18、28 :擴散板 19、29 :稜鏡片 33、33a、33b、43、43a、43b、53、53a :光學板材 35、45、55 :光出射開口 :延壓立體圖案 33汪，、43 汪，、43b，、 53a， 6〇 ·液晶顯示面板 600 :液晶顯示裝置 141271584 ___ Office Year / January e-day repair (more) replacement page IX, invention description [Technical field of the invention] The present invention relates to a backlight module 'in particular, a type of use in the backlight module Optical sheet. [Prior Art] Backlight module refers to a component that can provide a back light source. It is currently used in various information, communication, and consumer products, such as liquid crystal display (LCD) and film scanner. , slide to see the box and other products. Generally speaking, the backlight module is mainly composed of three parts: a casing, an optical plate and a light source. According to the difference of the incident position of the light source, it can be divided into two types: edge lighting and bottom lighting. Backlight type backlight modules are commonly used in products requiring power saving and thinness such as portable computers. In order to achieve the requirements of lightness and thinness, a light source is usually placed on the side of the backlight module, and the light emitted from the light source is guided to the display panel by a light guide plate. The light guide plate uses a method of injection molding to compress a methyl methyl methacrylate (PMMA) into a smooth surface plate, and then screen printing on the bottom surface of the light guide plate with a material having light diffusion, or The diffusion point is directly generated by the injection molding method to destroy the total reflection of the light to refract the light out of the surface of the light guide plate, and then use the density or size of the point to achieve the initial homogenization effect. 5 1271584 _ 缸年月月月月修修) The replacement page is a conventional optical film between the display panel and the light source, such as a diffuser film (Diffuser film) or a cymbal (Prism). Fig. 1 is a schematic cross-sectional view showing a conventional side-lit backlight module. The side light type backlight module 1 is composed of a casing η, a light guide plate 12, a reflective film 14, at least one prism sheet 19, a plurality of light sources 16, and a diffusion film is. The prism lens is used to change the angle of light emission by the refraction of light, thereby increasing the brightness of the positive viewing angle. The main function of the diffuser is to scatter the emitted light to correct the original light source's viewing angle distribution, so as to eliminate the bright band and shadow of the light source, so that the brightness of the picture is more uniform and the atomization effect is achieved. A direct-lit backlight module is usually used in products such as televisions that require high brightness. In order to increase the brightness, a plurality of light sources are conventionally arranged directly below the display panel, so that the outline of the light source is easily displayed on the screen, resulting in uneven brightness of the overall picture. In order to solve the above problems, the prior art is to provide a diffusion plate and a plurality of optical films, such as a diffusion film (Diffuser film) and a Prism sheet, between the display panel and the light source. Fig. 2 is a schematic cross-sectional view showing a conventional direct type backlight module. The direct type backlight module 200 is composed of a casing 21, a reflection plate 24, a plurality of light sources 26, a cymbal plate 29, and a diffusion plate 28. However, the light guide plate of the side-lit backlight module is easy to produce uneven printing by screen printing. If the injection molding is used, the mold needs to be opened separately, and the cost is high; The arrangement of the diffusion diaphragm and the cymbal in the backlight module not only increases the material and assembly cost, but also wastes the space for the diaphragm to be placed. In the direct type backlight module, the diffusion plate is produced by adding a diffusing agent to the transparent plate. Although the diffusing agent can generate light scattering effect, it absorbs light and reduces light use efficiency. 1271584 It is therefore necessary to provide a set that combines light efficiency with the use of the next year. It is a replacement for the backlight uniformity of the improved optical sheet and the cost of materials and assembly. SUMMARY OF THE INVENTION It is therefore an object of the present invention to provide a backlight module that combines the uniformity of light and the cost of materials and assembly. The technical feature of the present invention is that a composite optical plate is manufactured by mechanical imprinting to replace the structure of the conventional plate with an additional optical film, thereby producing a uniform surface light source. According to the present invention, not only the use of the optical film sheet can be reduced, but also the absorption of the light source can be reduced, and the light use efficiency of the backlight film group can be improved. Moreover, the assembly process of the backlight module can be simplified. Therefore, the present invention not only achieves light use efficiency to increase the brightness of the liquid crystal display panel, but also can greatly reduce the material and assembly cost of the backlight film group, and meets the industrial requirements for thinning. [Embodiment] Please refer to Fig. 3, which is a schematic cross-sectional view of an edge-lit backlight module according to a first embodiment of the present invention. The structure of the edge-lit backlight module 300 shown in FIG. 3 is similar to that of the backlight module 100 of FIG. 1 . The biggest difference lies in the optical sheet, the diaphragm and the manufacturing method of the two backlight modules. The backlight module 300 of the present embodiment is composed of a housing 31, an optical plate 33, a reflective sheet 34, and a backlight 36. 7 1271584 #年^月β日修瘦) Replacement page The outer casing 3 1 is a closed structure, including a light exit opening 35, and the material of the outer casing 3 i includes a plasticized material, a metal material, or other opaque material. The main force b is supporting the greedy module and preventing light from leaking out of the light exit opening 35. The reflective sheet 34 is located on the innermost layer of the backlight module and is a highly reflective optical film or directly coated with a highly reflective material (for example, white paint) on the bottom 31 of the backlight module 300. The optical plate 33 is located between the reflective sheet 34 and the light exit opening 35, and is a light source propagation medium according to the design of the backlight module. The optical plate 33 may have a structure with different shapes, such as a wedge structure or a cubic structure, and a thickness range. Between 4.0mm and 12mm. In the second embodiment of the present invention, the optical sheet 3 3 is a cubic structure having a thickness of about 1 mm. The optical sheet 33 is formed by coextruding at least two materials using a one-step press process. In the first embodiment of the present invention, the optical sheet 3 3 is a two-layer structure in which a polycarbonate resin layer 33a and a methyl methacrylate polymer layer 331 are collectively stretched using a plastic platen technique. In still other embodiments of the present invention, the optical sheet may be a multi-layered structure in which a plurality of materials are coextruded. The material of the optical plate 33 may be, for example, a homopolymer or a copolymer of a highly transparent methyl methacrylate polymer, other soft optical films (for example, a diffusion plate, a transparent film), a polycarbonate resin, or MMA / styrene copolymer and the like. The optical sheet 33 has two pressure-extending surfaces, wherein at least one of the pressure-extending surfaces has a curved three-dimensional pattern 33a', and the curved three-dimensional pattern 33a is pre-marked on the rolling roller when the optical sheet is extruded. The stretched stereo 1271584 bell year/work month/3 day repair (received) is replacing the page pattern and is transferred onto the stretched surface by imprinting. The three-dimensional design of the 3D is designed to match different optical purposes, for example, in conjunction with the arrangement of the backlight 36, the increased brightness of the condensed light, or the adjustment of the light scattering. In some embodiments of the present invention, the profile of the three-dimensionally stretched pattern 33a may be symmetrical or asymmetrical, regular or irregular, wavy, serrated, square-toothed or other suitable pattern. In the first embodiment of the present invention, the stretched three-dimensional pattern 33a' is transferred onto the polycarbonate resin layer 33a to transfer a structure, which is used to replace the structure of the conventional backlight module. The light is concentrated by the refraction of the three-dimensional pattern 33a. Referring to Figure 4, there is shown a schematic cross-sectional view of an edge-lit backlight module according to a second embodiment of the present invention. The side-lit backlight module 4〇〇 structure shown in FIG. 4 is composed of a casing 41, an optical plate 43, a reflection sheet 44, and a backlight 46. Similar to the structure of the backlight module 300 of FIG. 3, the main difference is that the two sides of the optical plate 43 respectively have the extended three-dimensional patterns 43a, 43b, and the optical plate 33 shown in FIG. 3 has only one side. The three-dimensional pattern 33a is stretched. The optical sheet 43 is located between the reflective sheet 44 and the light exit opening 45 and is a light source propagation medium. Depending on the design of the backlight module, the optical sheet 43 can be of a different type, such as a wedge or cube structure, having a thickness ranging from 4.0 mm to 12 mm. In the second embodiment of the present invention, the optical sheet 43 is a cubic structure having a thickness of about 1 〇 mm. The optical sheet 43 is formed by using a stretching process to stretch at least one of the materials. In the second embodiment of the present invention, the optical sheet material 43 is a two-layer structure in which two materials are integrally stretched and formed. In the first embodiment of the present invention, the optical sheet may be a multilayer structure in which a plurality of materials are integrally formed by extrusion. The material of the optical plate 43 may be, for example, a homopolymer or a copolymer of a highly transparent methyl methacrylate polymer, other soft optics, such as a 'diffusion plate, a transparent film, a polycarbonate resin, and a crucible. A/ This ethylene copolymer, or other light-transmissive plastic material. In the second embodiment of the present invention, the optical sheet 43 is a two-layer structure in which a polycarbonate resin material 43a and a mercapto methacrylate polymer 43b are co-compressed using a plastic platen technique. In the second embodiment of the present invention, the stretched three-dimensional pattern 43a is transferred onto the methyl methacrylate polymer 43a by a regular zigzag pattern to replace the conventional prism sheet to pass the light. After the refraction of the three-dimensional pattern 43 a, the condensed light increases the luminance. The extended three-dimensional pattern 43b is formed by transferring an irregular mesh bump on the polycarbonate resin layer 4 3 b to replace the printing dot and the injection molding dot of the conventional light guide plate to destroy the total reflection of the light. The light passes through the polycarbonate resin material layer 4 3 b ' and is densely arranged by the rolling three-dimensional pattern 43b' to form a uniform surface light source. 5 is a schematic cross-sectional view of a direct type backlight module according to a third embodiment of the present invention. The structure of the backlight module 500 shown in FIG. 5 is similar to the structure of the backlight module 200 of FIG. 2, and the biggest difference lies in the optical sheets used in the two backlight modules and the manner in which they are manufactured. The backlight module 50 of the present embodiment is composed of a housing 51, an optical plate 53, a reflective sheet 54, and a backlight 56. The optical plate 53 is located between the reflective sheet 54 and the light exit opening 55, and is a light source propagation medium according to the design of the backlight module. The optical plate 53 can be 1271584 ___ β月日日修 (臭) positive replacement page f has different types The structure of the body, such as a wedge-shaped structure, or a cubic knot, is purely between 1.5 mm and 4 mm. In the third embodiment of the present invention, the optical sheet 53 is a cubic structure having a thickness of about 2 mm. The light-drying sheet 53 is formed by using a one-step press process to form at least two kinds of materials together. In the third embodiment of the present invention, the optical sheet material 53 is a two-layer structure in which two materials are integrally stretched and formed. In still other embodiments of the invention, the optical sheet may be a multilayer structure in which a plurality of materials are coextruded together. The material of the optical plate 53 may be, for example, a homopolymer or a copolymer of a south light transmissive methyl methacrylate polymer, other soft optical films (for example, a 'diffusion plate, a transparent film), a polycarbonate resin, MMA / styrene copolymer. In the third embodiment of the present invention, the optical sheet material 53 is a two-layer structure in which a polycarbonate resin material layer 53a and a methyl methacrylate polymer layer 53b are collectively formed by a plastic press plate technique. In the third embodiment of the present invention, the stretched three-dimensional pattern 53a is formed by transferring a regular zigzag pattern on the polycarbonate resin layer 53a to replace the conventional cymbal to allow the light to pass through the three-dimensional shape. After the refraction of the pattern 5 3 a, the condensed light increases the luminance. 53b is a monomethyl methacrylate polymer diffusion layer, and the light is transmitted through the diffusion layer to achieve a fogging effect. Fig. 6 is a schematic cross-sectional view showing a direct type rear liquid crystal display device according to a fourth embodiment of the present invention. The liquid crystal display device 600 shown in Fig. 6 is formed by combining a liquid crystal display panel 6G with the direct type backlight module 500 shown in Fig. 5. 1271584 荩伊月/3日修 (moving the replacement page in this embodiment, the backlight module 500 structure is composed of the outer casing 51, the optical plate 53, the reflection sheet 54, the backlight 56. The optical plate 53 is made of plastic The platen technology has a double-layered cubic structure of a polycarbonate resin material 53a and a f-based methyl acrylate polymer 53b, and has a thickness of about 2 mm. The curved surface of the optical plate 53 has a curved three-dimensional pattern 5 3 a 'After transferring a random optical pattern on the polycarbonate resin layer 5 3 a, the light condenses the light through the three-dimensional pattern 53a, and the light condenses the light to increase the brightness. 53b is a diffusion layer, and the light passes through the diffusion layer. The scattering treatment can achieve the effect of atomization. The backlight 56 uses a direct-type light source of a cold cathode fluorescent lamp. According to the preferred embodiment described above, the present invention can be used for two or more types by mechanical annealing. The plasticized material is jointly stretched to form an optical sheet' and simultaneously forms a three-dimensional pattern on the surface of the optical sheet to reduce or replace the use of the optical film sheet to reduce the amount of light absorption, thereby improving light. The efficiency of the backlight film group is increased by the efficiency, and the effect of eliminating the bright band and the shadow generated by the backlight is achieved; moreover, the distance between the backlight and the light-receiving substrate can be narrowed, and the thickness of the backlight film resistance is shortened. The invention can not only reduce the cost of the backlight module, simplify the assembly process of the backlight module, but also meet the requirements of the thinning of the backlight module. Through the embodiments described above, the reader can understand the technical features and advantages of the present invention. The embodiments described above are only intended to illustrate the technical content of the present invention and are not intended to limit the scope of the present invention. For example, the present invention uses a machine to jointly form two or more plasticized materials together to form an optical sheet. Forming the three-dimensional pattern of the optical plate to replace the traditional optical film 12 1271584 You are replacing the page in P month/3 days, producing a uniform scattering of visible light, eliminating the bright bands and shadows generated by the backlight' and shortening The thickness of the light propagation medium. However, the above embodiment only provides a better case, and the design of the three-dimensional pattern must match the emission of the light. The condition, the brightness requirement, and the configuration of the light source are changed to achieve different optical purposes. In addition, the choice of optical film material also affects the degree of light scattering and the distance of light diffusion. Therefore, the operation described in the embodiments of the present invention The conditions are not limited by the scope of the invention, and all operating conditions must be based on the wavelength of the light source used, the uniformity of light scattering, and the light utilization rate. Although the invention has been disclosed above in the preferred embodiment, Any of the skilled artisans will be able to make various modifications and refinements without departing from the spirit and scope of the invention, and the scope of the present invention is defined by the scope of the appended claims. BRIEF DESCRIPTION OF THE DRAWINGS In order to more fully understand the contents and technical advantages of the present invention described above, please refer to the above description and cooperate with the accompanying drawings. It must be emphasized that, according to the standard operating mode of the industry, different drawings are not drawn according to the revision rule. In fact, for the sake of clarity, different drawings may be arbitrarily enlarged or reduced. The illustration is as follows: Fig. 1 is a schematic cross-sectional view showing a conventional edge-lit backlight module. Fig. 2 is a schematic cross-sectional view showing a conventional direct type backlight module. Fig. 3 is a schematic cross-sectional view showing an edge-light type backlight module according to a first embodiment of the present invention. Fig. 4 is a schematic cross-sectional view showing a side-light type back-lighting module in accordance with a second embodiment of the present invention. Fig. 5 is a schematic cross-sectional view showing a direct type backlight module according to a second embodiment of the present invention. Fig. 6 is a schematic cross-sectional view showing a direct type rear liquid crystal display device according to a fourth embodiment of the present invention. [Description of main component symbols] 100, 200, 3 00, 400, 5 00: backlight module 11, 2 1 , 3 1 , 41, 5 1 : housing # 12, 22 · light guide plates 14, 24, 34, 44, 54: reflection sheets 16, 26, 36, 46, 56: backlights 18, 28: diffusion plates 19, 29: cymbals 33, 33a, 33b, 43, 43a, 43b, 53, 53a: optical sheets 35, 45, 55: light exit opening: extended three-dimensional pattern 33, 43, 44, 43b, 53a, 6 〇 liquid crystal display panel 600: liquid crystal display device 14