1271579 九、發明說明： 【發明所屬之技術領域】 本發明係關於一種背光模組，尤指一種出光輝度較高 之背光模組。 【先前技術】 液晶顯示模組為一種非自發光顯示裝置，其顯示主要 措由控制外部光源所發出光束之通過或者不通過來實現， 因此需要相應之背光或者前光模組，該背光或者前光模組 可將外部光源所發出之光束導向顯示面板，實現顯示功能。 请參閱第一圖’係一種習知液晶顯示模組1 00，其通常 包括一液晶面板101與一背光模組102。該背光模組102包括 一光源1021、一光源罩1022、一反射板1〇23、一導光板1024 及一反射偏光板1025。其中該光源1021位於導光板1〇24之 一側，該光源罩1022位於光源1021相對導光板1〇24之另一 側，反射該光源1021發出之光束，以增加導向導光板1〇24 之光強度，該反射板1023、導光板1024及反射偏光板1025 依次層疊放置，該反射偏光板1025位於導光板1〇24與液晶 面板101之間。由光源1021發出之光束可視為由二極化態相 互垂直之P偏光及S偏光組成，該導光板1〇24及反射板1023 將該光束導向反射偏光板1025，該反射偏光板1025將平行 於反射偏光板1025極化態之S偏光導向液晶面板101，並反 射垂直於反射偏光板1025極化態之P偏光。該反射之P偏光 經由導光板1024、反射板1023之反射再利用，而重新轉換 1271579 為強度相對較弱之p偏光及s偏光，如此可增加光源顧發 出光束之利用率。 惟，經由反射偏光板1025反射至導光板觀、反射板 1023之1>偏光將大部份被光_2ι發出之光束所吸收，致 使光源1021發出光束之利用率提高較少。同時，由於該背 光模組搬未制擴散板或相應起之元件，致使通過反射 偏光板1〇25之光束分佈不均句，液晶面板脚示效果較 差。 請參閱第二圖’為2002年9月则公告之美國專利第 6,448,955號揭示的-種液晶顯示模組，其包括一液晶 面板201及一背光模組202,該液晶面板2〇1包括一第一基板 2011、一液晶層2012及一第二基板2〇13。該背光模組2〇2 包括二光源2021、分別與二光源2〇21相對應之二光源罩 2022、 分別與光源2021相對應之導光板2024、一反射板 2023、 一 擴政板2025、增 το 片（Brightness Enhance Film，BEF) 2026、一反射偏光板（Double Brightness Enhance Film， DBEF) 2027及一覆蓋層 2028。 請一併參閱第三圖，該液晶顯示模組200工作時，光源 2021發出一可視為由二極化態相互垂直之p偏光及s偏光 組成之光束，該光束經由導光板2024、擴散板2025及增亮 片2026後到達反射偏光板2027，其中該P偏光之極化態垂 直於反射偏光板2027之極化態，該S偏光之極化態平行於 反射偏光板2027之極化態，故，僅S偏光能通過反射偏光 板2027，而P偏光被反射偏光板2027反射，該反射之P偏光 1271579 經增亮片2026、擴散板2025、導光板2024及反射板2023後 重新轉換成強度相對較弱之S偏光及P偏光，其中S偏光部 份將通過反射偏光板2027，P偏光被反射。該背光模組202 採用擴散板2025，可實現光束之均勻出射。惟，由該反射 偏光板2027反射之P偏光大部份為光源2021發出之光束所 吸收，同時該反射之P偏光重新轉換為S偏光及P偏光時經 過複數介面，其能量將減弱，反射光束之重新利用率較低。 有鑑於此，提供一種高輝度、低耗電及低成本之背光 模組實為必需。 【發明内容】 本發明之目的在於提供一種高輝度、低耗電及低成本 之背光模組。 本發明之背光模組包括一光源、一導光板、一擴散板 及一反射偏光板，其中該導光板係用以接收光源發出之光 束，該擴散板用以將導光板導出之光束擴散後導出，該反 射偏光板將該光束之S偏光導向一液晶面板，反射該光束 之P偏光部份，其中，該導光板、擴散板及反射偏光板依 序層疊放置，導光板位於該光源一侧，該擴散板之表面設 置複數稜鏡結構。 本發明之背光模組，其擴散板之表面設置複數稜鏡結 構，該稜鏡結構可將反射偏光板反射之P偏光重新轉換為 一具P偏光及S偏光之光束，而無需藉由導光板及反射板之 作用，可減少該反射偏光板反射之P偏光重新形成一具P偏 光及S偏光之光束而需經過的介面，減少介面損失，從而 1271579 提1¾透過反射偏光板之光束強度，進而增加背光模組之出 光輝度。 【實施方式】 請參閱第四圖，係本發明背光模組之第一實施方式， 該背光模組包括一光源3021、一光源罩3022、一反射板 3023、一導光板3024、一擴散板3〇25及一反射偏光板3026。 光源3021位於導光板3024之一侧，光源罩3022罩於光源 3021相對導光板3024之另一侧，反射板3023、導光板3024、 擴散板3025及反射偏光板3026依序疊放。擴散板3025上設 置有複數V形槽（未標示），藉此形成複數稜鏡結構1。 請參閱第五圖，光源3021發出之光束進入導光板 3024 ’藉由導光板3〇24及反射板3〇23將該光束導向擴散板 3025、反射偏光板3026。該光束可視為由二極化態相互垂 直之P偏光及S偏光組成，其中S偏光通過反射偏光板 3026，P偏光被反射偏光板3〇26反射至擴散板3025。擴散 板3025之稜鏡結構1反射、散射該p偏光，重新形成能量相 對較小之光束，該光束亦可視為由二極化態相互垂直之p 偏光及s偏光組成。該光束到達反射偏光板3〇26後，其中$ 偏光通過反射偏光板3026，P偏光被反射偏光板3026反 射。藉此光束中之p偏光於反射偏光板3〇26、擴散板3〇25 之間轉換為相應之P偏光與S偏光，無需藉由導光板3024及 反射板3023之反射，可減少光束透過之介面，減少能量之 介面相失’進而增加透過反射偏光板3〇26之光能量，達到 增加背光模組出光輝度之目的。 1271579 請一併參閱第六圖、第七圖，該擴散板3025可沿一平 行方向均勻設置V形槽（未標示），形成平行之條形稜鏡結構 11。該擴散板3025亦可同時沿二垂直方向均勻設置v形槽 (未標示），形成均勻分佈之金字塔形稜鏡結構12。 請參閱第八圖，係本發明背光模組之第二實施方式， 該背光模組包括一光源4021、一光源罩4022、一導光板 4024、 一形成於導光板4024表面之反射膜4023、一擴散板 4025、 一增亮片4026及一反射偏光板4027。該背光模組與 第四圖所示之背光模組相比，區別在於導光板4024為楔 形，該導光板4024具反射膜4023以替代第一實施方式之反 射板3023，其於擴散板4025與反射偏光板4027之間增設一 增亮片4026。該增亮片4026可使該背光模組獲得更高之出 光輝度。 光源4021發出之光束進入導光板4〇24，藉由導光板 4〇24及反射膜4023將該光束導向擴散板4025、增亮片4026 及反射偏光板4027。該光束可視為由二極化態相互垂直之 P偏光及S偏光組成，其中S偏光通過反射偏光板4027，P偏 光被反射偏光板4027反射。該反射之p偏光經由增亮片 4026到達擴散板4025。擴散板4025之稜鏡結構2反射、散射 該P偏光，重新形成能量相對較小之光束，該光束亦可視 為由二極化態相互垂直之P偏光及；5偏光組成。該光束通過 增免片4026後到達反射偏光板4027，其中S偏光通過反射 偏光板4027，P偏光被反射偏光板4〇27反射。藉此，光束 中之P偏光於反射偏光板4027、增亮片4026及擴散板4025 11 1271579 =換為相應之P偏光與s偏光，無需藉由導光板響及 =膜:〇23之反射，可減少光束透過之介面，減少能量之 ^ ^ 1進而增加透過反射偏光板4027之光能量，達到 曰加月光模組出光輝度之目的。 =之背光模組，其背光模組之光源可採用多個， 可為點光源或線光源，其相對導光板之側面設置。 擴政板之稜鏡結構非僅㈣㈣分佈，亦可設置為非 « /刀佈。該導光板可為平板形或楔形，其 板另二 側可設置複數網點。 敬<另 利申ί上戶Γ，本發明符合發明專利要件，爰依法提出專 安惟’以上所述者僅為本發明之較佳實施例，舉凡 案技藝之人士，在援依本案發明精神所作之等 飾或變化，皆應包含於以下之中請專利範圍内。、〜 【圖式簡單說明】 第一圖係一種先前液晶顯示模組之截面圖。 第：圖係另一種先前液晶顯示模組之截面圖。1271579 IX. Description of the Invention: [Technical Field] The present invention relates to a backlight module, and more particularly to a backlight module having a high luminance. [Prior Art] The liquid crystal display module is a non-self-luminous display device whose display mainly controls the passage or non-passage of the light beam emitted by the external light source, and therefore requires a corresponding backlight or front light module, the backlight or the front light The module can guide the light beam emitted by the external light source to the display panel to realize the display function. Referring to FIG. 1 is a conventional liquid crystal display module 100, which generally includes a liquid crystal panel 101 and a backlight module 102. The backlight module 102 includes a light source 1021, a light source cover 1022, a reflective plate 1〇23, a light guide plate 1024, and a reflective polarizing plate 1025. The light source cover 1021 is located on one side of the light guide plate 1〇24. The light source cover 1022 is located on the other side of the light source 1021 opposite to the light guide plate 1〇24, and reflects the light beam emitted by the light source 1011 to increase the light of the light guide plate 1〇24. The reflection plate 1023, the light guide plate 1024, and the reflective polarizing plate 1025 are sequentially stacked, and the reflective polarizing plate 1025 is located between the light guide plate 1 24 and the liquid crystal panel 101. The light beam emitted by the light source 1021 can be regarded as consisting of P-polarized light and S-polarized light which are perpendicular to each other in a dipolarized state. The light guide plate 1 〇 24 and the reflecting plate 1023 guide the light beam to the reflective polarizing plate 1025, and the reflective polarizing plate 1025 will be parallel to The S-polarized light of the reflective polarizing plate 1025 is guided to the liquid crystal panel 101, and reflects the P-polarized light perpendicular to the polarization state of the reflective polarizing plate 1025. The reflected P-polarized light is reused by the reflection of the light guide plate 1024 and the reflection plate 1023, and the 1271579 is re-converted into a relatively weak p-polarized light and s-polarized light, thereby increasing the utilization ratio of the light source. However, the light reflected from the reflective polarizing plate 1025 to the light guide plate and the reflecting plate 1023> the polarized light is mostly absorbed by the light beam emitted from the light, so that the utilization of the light emitted from the light source 1021 is less improved. At the same time, since the backlight module does not have a diffusing plate or a corresponding component, the light beam passing through the reflective polarizing plate 1 〇 25 is unevenly distributed, and the liquid crystal panel has a poor effect. The liquid crystal display module includes a liquid crystal panel 201 and a backlight module 202. The liquid crystal panel 201 includes a first liquid crystal display module disclosed in the above-mentioned U.S. Patent No. 6,448,955. A substrate 2011, a liquid crystal layer 2012 and a second substrate 2〇13. The backlight module 2〇2 includes two light sources 2021, two light source covers 2022 corresponding to the two light sources 2〇21, a light guide plate 2024 corresponding to the light source 2021, a reflective plate 2023, and a expansion plate 2025. A Brightness Enhance Film (BEF) 2026, a Double Brightness Enhance Film (DBEF) 2027, and a cover layer 2028. Referring to the third figure, when the liquid crystal display module 200 is in operation, the light source 2021 emits a light beam which can be regarded as a p-polarized light and a s-polarized light which are perpendicular to each other in a dipolarized state, and the light beam passes through the light guide plate 2024 and the diffusion plate 2025. And the brightness enhancing sheet 2026 reaches the reflective polarizing plate 2027, wherein the polarization state of the P polarized light is perpendicular to the polarization state of the reflective polarizing plate 2027, and the polarization state of the S polarized light is parallel to the polarization state of the reflective polarizing plate 2027. Only the S polarized light can pass through the reflective polarizing plate 2027, and the P polarized light is reflected by the reflective polarizing plate 2027. The reflected P polarized light 1271579 is reconverted to a relatively weak intensity after being brightened by the brightening sheet 2026, the diffusing plate 2025, the light guiding plate 2024 and the reflecting plate 2023. The S polarized light and the P polarized light, wherein the S polarized portion will pass through the reflective polarizing plate 2027, and the P polarized light is reflected. The backlight module 202 uses a diffusion plate 2025 to achieve uniform beam emission. However, most of the P-polarized light reflected by the reflective polarizing plate 2027 is absorbed by the light beam emitted by the light source 2021, and the reflected P-polarized light is converted into S-polarized light and P-polarized light through a plurality of interfaces, and the energy thereof is weakened, and the reflected light beam is reflected. The reutilization rate is low. In view of this, it is necessary to provide a backlight module with high luminance, low power consumption and low cost. SUMMARY OF THE INVENTION An object of the present invention is to provide a backlight module with high luminance, low power consumption, and low cost. The backlight module of the present invention comprises a light source, a light guide plate, a diffusing plate and a reflective polarizing plate, wherein the light guiding plate is configured to receive a light beam emitted by the light source, and the diffusing plate is used for diffusing the light beam derived from the light guide plate and then deriving The reflective polarizing plate directs the S-polarized light of the light beam to a liquid crystal panel, and reflects the P-polarized portion of the light beam. The light guide plate, the diffusion plate and the reflective polarizing plate are sequentially stacked, and the light guide plate is located on one side of the light source. The surface of the diffuser plate is provided with a plurality of turns. In the backlight module of the present invention, the surface of the diffusion plate is provided with a plurality of 稜鏡 structures, which can convert the P-polarized light reflected by the reflective polarizing plate into a P-polarized and S-polarized light beam without using a light guide plate. And the function of the reflecting plate can reduce the interface of the P-polarized light reflected by the reflective polarizing plate to re-form a P-polarized and S-polarized light beam, thereby reducing the interface loss, thereby increasing the beam intensity of the reflective polarizing plate by 1271579, and further Increase the brightness of the backlight module. The first embodiment of the backlight module of the present invention includes a light source 3021, a light source cover 3022, a reflection plate 3023, a light guide plate 3024, and a diffusion plate 3. 〇25 and a reflective polarizing plate 3026. The light source 3021 is located on one side of the light guide plate 3024, and the light source cover 3022 is disposed on the other side of the light source 3021 opposite to the light guide plate 3024. The reflection plate 3023, the light guide plate 3024, the diffusion plate 3025 and the reflective polarizing plate 3026 are sequentially stacked. The diffusion plate 3025 is provided with a plurality of V-shaped grooves (not shown), thereby forming a plurality of 稜鏡 structures 1. Referring to FIG. 5, the light beam emitted from the light source 3021 enters the light guide plate 3024'. The light beam is guided to the diffuser plate 3025 and the reflective polarizing plate 3026 by the light guide plate 3〇24 and the reflection plate 3〇23. The light beam may be composed of P-polarized light and S-polarized light which are perpendicular to each other in a dipolarized state, wherein the S-polarized light passes through the reflective polarizing plate 3026, and the P-polarized light is reflected by the reflective polarizing plate 3〇26 to the diffusing plate 3025. The structure 1 of the diffuser plate 3025 reflects and scatters the p-polarized light to reform a relatively small beam of energy, which can also be regarded as consisting of p-polarized and s-polarized light whose polarization states are perpendicular to each other. After the light beam reaches the reflective polarizing plate 3〇26, the polarized light passes through the reflective polarizing plate 3026, and the P polarized light is reflected by the reflective polarizing plate 3026. The p-polarized light in the light beam is converted into the corresponding P-polarized light and the S-polarized light between the reflective polarizing plate 3〇26 and the diffusing plate 3〇25, and the reflection of the light guide plate 3024 and the reflecting plate 3023 is eliminated, and the light beam can be reduced. The interface reduces the energy interface loss and further increases the light energy transmitted through the reflective polarizer 3〇26, thereby increasing the brightness of the backlight module. 1271579 Please refer to the sixth and seventh figures together. The diffuser plate 3025 can uniformly arrange V-shaped grooves (not shown) in a parallel direction to form a parallel strip-shaped structure 11 . The diffuser plate 3025 can also uniformly form a v-shaped groove (not shown) in two perpendicular directions to form a uniformly distributed pyramid-shaped dome structure 12. Referring to FIG. 8 , a second embodiment of the backlight module of the present invention includes a light source 4021 , a light source cover 4022 , a light guide plate 4024 , and a reflective film 4023 formed on the surface of the light guide plate 4024 . A diffuser plate 4025, a brightness enhancing sheet 4026, and a reflective polarizing plate 4027. The backlight module is different from the backlight module shown in FIG. 4 in that the light guide plate 4024 has a wedge shape, and the light guide plate 4024 has a reflective film 4023 instead of the reflective plate 3023 of the first embodiment, and is disposed on the diffusion plate 4025. A brightness enhancing sheet 4026 is added between the reflective polarizing plates 4027. The brightness enhancing film 4026 allows the backlight module to obtain a higher brightness. The light beam emitted from the light source 4021 enters the light guide plate 4〇24, and the light beam is guided to the diffusion plate 4025, the brightness enhancement plate 4026, and the reflective polarizing plate 4027 by the light guide plate 4〇24 and the reflection film 4023. The light beam can be regarded as consisting of P-polarized light and S-polarized light whose mutually polarized states are perpendicular to each other, wherein the S-polarized light passes through the reflective polarizing plate 4027, and the P-polarized light is reflected by the reflective polarizing plate 4027. The reflected p-polarized light reaches the diffuser plate 4025 via the brightness enhancing sheet 4026. The 稜鏡 structure 2 of the diffuser plate 4025 reflects and scatters the P-polarized light, and re-forms a light beam having a relatively small energy, and the light beam can also be regarded as a P-polarized light which is perpendicular to the two polarization states and 5 polarized light. The light beam passes through the augmentation sheet 4026 and reaches the reflective polarizing plate 4027, wherein the S polarized light passes through the reflective polarizing plate 4027, and the P polarized light is reflected by the reflective polarizing plate 4? Thereby, the P polarized light in the light beam is reflected on the reflective polarizing plate 4027, the brightness enhancing sheet 4026, and the diffusing plate 4025 11 1271579 = the corresponding P polarized light and the s polarized light, without the reflection of the light guide plate and the film: 〇23, Reducing the light transmission interface, reducing the energy of ^ ^ 1 and increasing the light energy transmitted through the reflective polarizing plate 4027, to achieve the purpose of adding the luminous brightness of the moonlight module. The backlight module has a plurality of light sources for the backlight module, and can be a point source or a line source, which is disposed opposite to the side of the light guide plate. The structure of the expansion board is not only (four) (four) distribution, but also can be set to non-« / knife cloth. The light guide plate may be in the shape of a flat plate or a wedge, and a plurality of dots may be disposed on the other two sides of the plate. The invention conforms to the patent requirements of the invention, and the invention is based on the law. The above is only a preferred embodiment of the present invention, and the person skilled in the art is invented in the case of the invention. All ornaments or changes made by the spirit shall be included in the following patents. , ~ [Simple description of the diagram] The first diagram is a cross-sectional view of a previous liquid crystal display module. The figure: is a cross-sectional view of another prior liquid crystal display module.
第二圖係第二圖之液晶顯示模組之光路圖。 苐六圖係第四 苐七圖係第四 立體圖。 明背光模組之第—實施方式之戴面圖 弟五圖係苐四圖所示背光模組之光路圖。 口 圖所示擴散板之稜鏡結構立體圖。 圖所示擴散板之稜鏡結構另一實於 、 工Vi 面圖。 第八圖係本發明背光模組之第二實施方式之截 【主要元件符號說明】 12 1271579 光源 反射板 反射板 增亮片 稜鏡結構 3021 、 4021 3023 3024 > 4024 4026 光源罩 反射膜 擴散板 反射偏光板 3022 > 4022 4023 3025 、 4025 3026 > 4027 1、2、11、12The second figure is the optical path diagram of the liquid crystal display module of the second figure. The sixth picture is the fourth three-dimensional picture. The front view of the backlight module is the light path diagram of the backlight module shown in the fourth figure. The perspective view shows the structure of the diffuser plate. The figure shows the structure of the diffuser plate, which is another real and mechanical Vi. The eighth embodiment is a cross-section of the second embodiment of the backlight module of the present invention. [Main component symbol description] 12 1271579 Light source reflector reflector plate brightness enhancement sheet structure 3021, 4021 3023 3024 > 4024 4026 Light source cover reflection film diffusion plate reflection Polarizer 3022 > 4022 4023 3025 , 4025 3026 > 4027 1, 2, 11, 12
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