M362423 五、新型說明： 【新型所屬之技術領域】 本創作是有關於一種背光模組，且特別是有關於使用發光 二極體或雷射二極體的背光模組及其在液晶顯示裝置上的應 用。 【先前技術】 液晶顯示器（Liquid Crystal Display，LCD)具有高書質、體 ^ 積小、重量輕、低驅動電壓、與低消耗功率等優點，因此被廣 泛應用於各種通訊或電子產品。液晶顯示器大部分為背光型液 晶顯不器，其係由液晶顯示面板及背光模組所組成。因此，背 光模組為液晶顯示器中相當關鍵之零組件之一。背光模組可依 照光源入射位置的不同分成侧向式入光（Edge Lighting)與直下 式入光（BottomLighting)兩種，藉以提供液晶顯示器一面光源。 以背光模組的背光源為發光二極體（Light EmittingM362423 V. New description: [New technical field] This creation is related to a backlight module, and in particular to a backlight module using a light-emitting diode or a laser diode and its use on a liquid crystal display device Applications. [Prior Art] A liquid crystal display (LCD) has a high book quality, a small volume, a light weight, a low driving voltage, and a low power consumption, and is therefore widely used in various communication or electronic products. Most of the liquid crystal displays are backlight type liquid crystal display devices, which are composed of a liquid crystal display panel and a backlight module. Therefore, the backlight module is one of the most critical components in the liquid crystal display. The backlight module can be divided into two types: edge lighting and BottomLighting depending on the incident position of the light source, thereby providing a light source for the liquid crystal display. The backlight of the backlight module is a light emitting diode (Light Emitting)
Diode，LED)來舉例說明，由於發光二極體具有低耗電量、低 籲發熱篁、操作壽命長、耐撞擊、體積小、反應速度快、以及可 發出穩定波長的色光等良好光電特性，因而適合應用於背光模 組之光源。 目别，當使用發光二極體來作為背光模組之光源時，其需 設置多個發光二極體於一電路板上，以組成發光燈條（UghtBar) 來提供背光源。然而，發光燈條需設有多個發光二極體，以提 供凴度足夠之光源，因而增加發光二極體的設置成本，且這些 發光一極體之間具有間隙，而容易產生整體發光不均勻的情 形，因而影響背光模組的背光均勻性。 M362423 【新型内容】 因此本創作之一方面係在於提供一種背光模組及其應用 的液晶顯示裝置，藉以減少光源的設置數量，因而可減少成本。 • 本創作之另一方面係在於提供一種背光模組及其應用的 液晶顯示裝置，藉以提升背光模組的背光均勻性。 本創作之又一方面係在於提供一種背光模組及其應用的 液晶顯示裝置，藉以適用於如發光二極體或雷射二極體等具有 • 高指向性的背光源。 根據本創作之實施例，本創作之背光模組包含光源、反射 腔體及導光板。光源係設置於反射腔體的一端，反射腔體包括 出光口 ’其中當光源發光時，光源的光線係入射於反射腔體中 來進行反射，並由反射腔體的出光口來出光。導光板設置於反 射腔體的一側，並具有入光面，其面對於反射腔體的出光口。 又’根據本創作之實施例’上述背光模組可應用於液晶顯 示裝置中。 # 因此’本創作之背光模組及其應用的液晶顯示裝置可適用 於如發光二極體或雷射二極體等具有高指向性的背光源，且可 減少光源的設置數量，以減少背光模組的成本 。再者，光源的 發光可在反射腔體内均勻地進行混光’因而大幅地提升背光模 組的背光均勻性。 【實施方式】 為讓本創作之上述和其他目的、特徵、優點與實施例能更 明顯易懂，本說明書將特舉出一系列實施例來加以說明。但值 得注思的是，此些實施例只是用以說明本創作之實施方式，而 M362423 - 非用以限定本創作。 請參照圖1和圖2,圖1係緣示依照本創作之第-實施例 之液晶顯示面板與背光模組的局部剖面示意圖，圖2係緣示依 -照本創作之第-實施例之光源、導光板及反射腔體的分解立體 .示意圖。本實施例的背光模組⑽為侧向式入光背光模組，並 與液晶顯示面板200組合，而形忐饬曰 办成*液晶顯不裝置。背光模組100 包含框架110、光源120、導光板13〇、反射腔體14〇、擴散板 150及光學膜片組16〇。框架UG係用以組裝和承載上述光源 • 12〇、導光板130、反射腔體I40及光學膜片組16〇。導光板130 係設置於反射腔體14〇的一侧，光源12〇係設置於反射腔體14〇 的一端，用以發出光線來入射至反射腔體14〇中且光線可在 反射腔體140内進行反射，並由反射腔體14〇出光至導光板13〇 中。擴散板150係設置於光源120與反射腔體14〇之間，用以 擴散光源120的光線，增加發光均勻性。光學膜片組16〇設置 於導光板130的上方，以改善導光板13〇出光的光學效果。 如圖1和圖2所示，本實施例的框架11〇例如係以高強度 • 的金屬或塑膠材料所製成，以保護和承載上述元件。本實施例 的光源120例如為：發光二極體、有機發光二極體（〇rganic UghtDiode, LED) to illustrate, because the light-emitting diode has low photoelectricity, low heat generation, long operating life, impact resistance, small volume, fast response, and good photoelectric properties such as color light that can emit stable wavelengths, Therefore, it is suitable for the light source of the backlight module. When using a light-emitting diode as the light source of the backlight module, it is required to provide a plurality of light-emitting diodes on a circuit board to form a light bar (UghtBar) to provide a backlight. However, the light bar needs to be provided with a plurality of light emitting diodes to provide a light source with sufficient intensity, thereby increasing the installation cost of the light emitting diodes, and having a gap between the light emitting bodies, and easily generating overall light. Uniform situation, thus affecting the backlight uniformity of the backlight module. M362423 [New content] Therefore, one aspect of the present invention is to provide a backlight module and a liquid crystal display device thereof, thereby reducing the number of light sources and thus reducing the cost. • Another aspect of the present invention is to provide a backlight module and a liquid crystal display device therefor, thereby improving the backlight uniformity of the backlight module. Another aspect of the present invention is to provide a backlight module and a liquid crystal display device therefor, which are suitable for a backlight having a high directivity such as a light emitting diode or a laser diode. According to an embodiment of the present invention, the backlight module of the present invention comprises a light source, a reflective cavity and a light guide plate. The light source is disposed at one end of the reflective cavity, and the reflective cavity includes a light exit port. Wherein, when the light source emits light, the light of the light source is incident on the reflective cavity for reflection, and is emitted by the light exit of the reflective cavity. The light guide plate is disposed on one side of the reflective cavity and has a light incident surface facing the light exit opening of the reflective cavity. Further, the backlight module described above can be applied to a liquid crystal display device according to an embodiment of the present invention. # Therefore, the backlight module of the present invention and the liquid crystal display device thereof can be applied to a backlight having high directivity such as a light-emitting diode or a laser diode, and the number of light sources can be reduced to reduce the backlight. The cost of the module. Furthermore, the illumination of the light source can uniformly mix light within the reflective cavity' thus greatly improving the backlight uniformity of the backlight module. The above and other objects, features, advantages and embodiments of the present invention will become more apparent and understood. However, it is worth noting that these examples are merely illustrative of the implementation of the present work, and M362423 - is not intended to limit the creation. 1 and FIG. 2, FIG. 1 is a partial cross-sectional view showing a liquid crystal display panel and a backlight module according to a first embodiment of the present invention, and FIG. 2 is a diagram showing a first embodiment of the present invention. The exploded perspective of the light source, the light guide plate and the reflective cavity. The backlight module (10) of the embodiment is a lateral light-in which backlight module, and is combined with the liquid crystal display panel 200, and is formed into a liquid crystal display device. The backlight module 100 includes a frame 110, a light source 120, a light guide plate 13A, a reflective cavity 14A, a diffusion plate 150, and an optical film group 16A. The frame UG is used to assemble and carry the above-mentioned light source, 12 〇, light guide plate 130, reflective cavity I40, and optical film set 16A. The light guide plate 130 is disposed on one side of the reflective cavity 14〇, and the light source 12 is disposed at one end of the reflective cavity 14〇 for emitting light to be incident into the reflective cavity 14〇 and the light can be in the reflective cavity 140 The inside is reflected, and the light is taken out by the reflecting cavity 14 into the light guide plate 13A. The diffuser 150 is disposed between the light source 120 and the reflective cavity 14〇 to diffuse the light of the light source 120 to increase uniformity of illumination. The optical film group 16 is disposed above the light guide plate 130 to improve the optical effect of the light emitted from the light guide plate 13. As shown in Figures 1 and 2, the frame 11 of the present embodiment is made, for example, of a high strength metal or plastic material to protect and carry the above components. The light source 120 of this embodiment is, for example, a light emitting diode, an organic light emitting diode (〇rganic Ught)
Emitting Diode ’ 〇LED)、雷射二極體（Laser Diode，LD)或電激 發光元件（Electro-Luminescence ’ EL) ’較佳為具有高能量或高 指向性的發光二極體或雷射二極體（半導體雷射）^在本實施例 中’光源120例如可為多個不同光色（如紅光、綠光及藍光）的 LED晶粒，亦可為單一白光LED晶粒。 如圖1和圖2所示，本實施例的導光板13 〇係設置於反射 腔體140的一侧，以導引出光至液晶顯示面板2〇〇，導光板130 可利用射出成型的方式來製成平板形結構或楔形板結構，其材 M362423 質例如為光硬化型樹脂、聚曱基丙烯酸曱酯（PMMA)、聚碳酸 醋（PC)或環烯（CyCl〇〇lefin)系樹脂材料。導光板13〇包括出光面 131、光反射面132及入光面133。出光面131係位於導光板 130的正面，藉以允許出光。光反射面132係位於導光板13〇 '的底面，且相對於出光面13丨。入光面133形成於導光板13〇 之一側，其鄰接於反射腔體140，用以使反射腔體14〇内所反 射的光線可由入光面133入射於導光板13〇中。 在一實施例中，出光面131的表面可選擇設有複數個稜形 • 或半圓形突出結構，藉以進一步修正光線的方向，而增加聚光 效果值传/主意的疋，導光板130之出光面131亦可具有霧面 處理或散射點設計，藉以均勻化導光板13〇的出光，減少出光 不均（Mura)的現象。 本實施例的導光板130可設有導光結構（未繪示）於光反射 面132上，藉以反射導引由光源12〇所發出的光線可由出光面 131射出，較佳為正向射出（正向出光）。導光板13〇的導光結構 例如為呈連續性的v形結構（亦即v_Cut結構）、霧面結構或散 • 射點結構，藉以導引入射於導光板130内的光線可充分地由出 光面131射出。且導光板13〇的入光面133可具有例如：v形 結構（V-Cut)、S形波浪結構或表面粗糙化處理（未繪示），藉以 提升光線的入射效率和光耦合效率。 在實施例中，導光板130與框架11〇之間可設置反射片 (未繪示）或形成（例如塗佈）反射層（未繪示），以反射光線。 請參照圖2、圖3A、圖3B及圖3C，圖3A至圖3C係綠 不依照本創作之第-實施例之光源、導光板及反射腔體的局部 立體示意圖。本實施例的反射腔體14〇係設置於導光板13〇的 一側，反射腔體140可為長矩形柱體或長圓形柱體，其包括入 M362423 - 光口 141、出光口 142及腔體内側層143，反射腔體140在入 光口 141和出光口 142之外的外侧表面較佳為不透光材料 144，以避免光線外露，反射腔體140内的介質較佳為透光介 質，例如：空氣、玻璃或高透光性樹脂，藉以允許光線在反射 • 腔體14〇内進行反射。入光口 141係形成於反射腔體14〇的一 端，用以允許光源120的光線可入射於反射腔體14〇中。出光 口 142係形成於反射腔體14〇的一側上，並對位於導光板13〇 的入光面133，用以允許在反射腔體14〇内反射的光線可出光 _於導光板130中，其中出光口 142的開口形狀可為任意幾何形 狀，例如圓形（如圖3A所示）、三角形（如圖3B所示）、矩形（如 圖3C所示）或楕圓形。在本實施例中，反射腔體14〇可開設有 複數個出光口 142,其佈設於反射腔體14〇的一側上以出光 於導光板130中。腔體内侧層143之材料例如為高反射率材料 或螢光體材料，其形成於反射腔體14〇的内側壁上，且未覆蓋 住暴露入光口 141和出光σ 142’其中高反射率材料可形成反 射片或反射塗層，此高反射率材料例如為銀、銘、金、絡、銅、 ，銦、銥、鎳、錄、銖、铑、錫、鈕、鎢、錳、上述任音合金， 或对黃化且咐熱之白色反射漆料(如二氧化鈦)，用以在反射腔 體140内反射光線。 虽腔體円側滑…列如為螢光體材料時，光源12 發出的光線可為可見光或非可見光（較佳為紫外光），以激發為 光體材料來發出螢光’並可在反射腔體140内進行反射。— 如圖2所示，在本實施例中，反射腔體14_ ^ =膠^的中空殼體’此時，反射腔體i4Q内的介質即為㈣ 的空跳，而人光口 141和出光口 142可利用衝愿或造 式來形成於反射腔體14()上，腔體内側層⑷可形成於_ M362423 内側壁上。 在一實施例中，反射腔體140内的介質例如為玻璃或高透 光性樹脂，此時，可在玻璃或透光性樹脂的柱體上形成腔體内 • 侧層143 ’並暴露入光口 141和出光口 142，接著，在腔體内 - 側層143上形成（例如塗佈）不透光材料144，因而形成反射腔體 140 〇 值得注意的是，如第2圖所示，本實施例的反射腔體14〇 較佳為長形柱體，其具有周圍的側面和相對兩端的端面，此端 ® 面的面積係小於侧面的面積。而導光板130係設置於長形反射 腔體140的周圍側面上（一側），光源12〇和擴散板15〇係設置 於反射腔體140之相對兩端面的其中一者上（一端）。 請參照圖2、圖4A及圖4B，圖4A與圖4B係繪示依照本 創作之第一實施例之擴散板的側面示意圖。本實施例的擴散板 150係用以擴散入射於反射腔體14〇的光線，其中擴散板15〇 在面對於入光口 141的表面上可選擇設有複數個稜形（如圖4A 所示）或半圓形（如圖4B所示）突出結構，以進一步改善光學效 # 果。本實施例之光學膜片組160例如為：擴散片、稜鏡片、增 焭膜或上述之任意組合，其設置於導光板13〇上，用以改善導 光板130的出光效果。 當背光模組1〇〇的光源12〇發光時，光源120的光線可藉 由擴散板150來進行擴散，並經由入光口 ι41來入射於反射腔 體140中。光線可在反射腔體14〇内持續地進行反射直到光 線由出光口 142出光至導光板13〇中。因此，即使光源12〇為 具有高指向性的發光二極體或雷射二極體，其發出的光線仍可 在反射腔體140内的持續反射下達到均勻混光的效果。再者， 本實施例的背光模組1〇〇僅需設置光源12〇於反射腔體14〇的 M362423 -一端’而非設置於導光板130的側面上，因而可減少背光模組 之光源（如LED晶粒）的數量及設置成本。 請參照圖5，其繪示依照本創作之第二實施例之背光模組 的局部剖面示意圖。相較於第一實施例，第二實施例之背光模 組可包含複數個光源、二反射腔體14〇a及二擴散板，其分別對 應地設置於導光板130的相對兩側，藉以由導光板13〇的相對 兩侧來導入光線。 請參照圖6 ’其繪示依照本創作之第三實施例之光源、導 擊 光板及反射腔體的局部正面示意圖。相較於第一實施例，第= 實施例之背光模組可包含複數個光源120b和二擴散板15〇b， 其分別對應地設置於反射腔體140b的相對兩端，其中光源12〇b 和擴散板150b的設置位置係平行於導光板13〇的出光面131。 此時，反射腔體140b可設有二入光口 ι41，其分別位於反射腔 體140b的相對兩端，藉以允許光線進入。 請參照圖7 ’其繪示依照本創作之第四實施例之光源、導 光板及反射腔體的正面示意圖。相較於第一實施例，第四實施 鲁 例之背光模組的反射腔體140c設有一出光口 142c，其形狀例 如為長矩形（如圖7所示）或長楕圓形，並對應於導光板丨3〇的 入光面133’用以允許在反射腔體14〇c内反射的光線可入射於 導光板130中。 請參照圖8A和圖8B，其繪示依照本創作之第五實施例之 光源、導光板及反射腔體的正面示意圖。相較於第一實施例， 第五實施例之反射腔體140d的出光口 i42d在遠離光源120處 之數量（如圖8A所示）或開口面積（如圖8B所示）係多於或大於 在靠近光源120處的數量或開口面積，亦即反射腔體14〇£1在 愈遠離光源120處，其出光口 142d的數量愈多或開口面積愈 M362423 ' 大，藉以增加此反射腔體140d在愈遠離光源120處的出光量。 由於反射腔體剛在愈遠離光源12〇處，其光線的光強度愈 低，因此，此實施例的反射腔體l4〇d可均勻光線的光強度^ 佈，藉以使光線均勻分佈地入射導光板13〇中，進而增加背光 模組的背光均勻性。 由上述本創作的實施例可知，本創作之背光模組及其應用 的液晶顯示裝置可使用如發光二極體或雷射二極體等光源來 作為背光源，且可減少光源（如LED晶粒）的設置數量，因而減 籲少背光模組的成本。再者，光源的發光可在反射腔體内不斷地 進行反射，直到光線出光至導光板中。因此，光源的發光可先 在反射腔體内均勻地混光，再入射於導光板，因而大幅地提升 背光模組的背光均勻性。 雖然本創作已以實施例揭露如上，然其並非用以限定本創 作，任何熟習此技藝者，在不脫離本創作之精神和範圍内，當 可作各種之更動與潤飾，因此本創作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】 為讓本創作之上述和其他目的、特徵、優點與實施例能更 明顯易懂，所附圖式之詳細說明如下： 圖1係繪示依照本創作之第一實施例之液晶顯示面板與背 先模組的局部剖面示意圖。 圖2係繪示依照本創作之第一實施例之光源、導光板及反 射腔體的分解立體示意圖。 圖3A至圖3C係繪示依照本創作之第一實施例之光源、導 光板及反射腔體的局部正面示意圖。 M362423 圖A”圖4B係繪不依照本創作之第一實施例之擴散板的 側面示意圖。 圖5係、會不依照本創作之第二實施例之背光模組的局部剖 面示意圖。 ® 6係繪示依照本創作之第三實施例之光源、導光板及反 射腔體的局部正面示意圖。 圖7係繪示依照本創作之第四實施例之光源、導光板及反 射腔體的正面示意圖。 圖8A和圖8B係繪示依照本創作之第五實施例之光源、導 光板及反射腔體的正面示意圖。 【主要元件符號說明】 100 :背光模組 110 :框架 120、120b :光源 130 :導光板 131 :出光面 132 :光反射面 133 :入光面Emitting Diode ' 〇LED), Laser Diode (LD) or Electro-Luminescence ' EL' is preferably a high-energy or high-directivity LED or laser II Polar body (semiconductor laser) ^ In the present embodiment, the light source 120 can be, for example, an LED crystal of a plurality of different light colors (such as red light, green light, and blue light), or a single white light LED die. As shown in FIG. 1 and FIG. 2, the light guide plate 13 of the embodiment is disposed on one side of the reflective cavity 140 to guide light to the liquid crystal display panel 2, and the light guide plate 130 can be formed by injection molding. It is made into a flat plate structure or a wedge plate structure, and the material M362423 is, for example, a photocurable resin, a polyacrylic acid acrylate (PMMA), a polycarbonate (PC) or a cycloalcene (CyCl〇〇lefin) resin material. The light guide plate 13A includes a light exiting surface 131, a light reflecting surface 132, and a light incident surface 133. The light exiting surface 131 is located on the front surface of the light guide plate 130 to allow light to be emitted. The light reflecting surface 132 is located on the bottom surface of the light guide plate 13A and is opposite to the light emitting surface 13A. The light incident surface 133 is formed on one side of the light guide plate 13A, and is adjacent to the reflective cavity 140 for allowing the light reflected in the reflective cavity 14 to be incident on the light guide plate 13 by the light incident surface 133. In an embodiment, the surface of the light-emitting surface 131 may be provided with a plurality of prismatic or semi-circular protruding structures, thereby further correcting the direction of the light, thereby increasing the convergence of the light-transmitting effect value/ideal, and the light guide plate 130 The light-emitting surface 131 may also have a matte surface treatment or a scattering point design to uniformize the light output of the light guide plate 13 to reduce the phenomenon of light emission unevenness (Mura). The light guide plate 130 of the embodiment may be provided with a light guiding structure (not shown) on the light reflecting surface 132, so that the light emitted by the light source 12A can be emitted from the light emitting surface 131, preferably in a forward direction ( Positive light). The light guiding structure of the light guide plate 13A is, for example, a continuous v-shaped structure (that is, a v_Cut structure), a matte structure or a scattered dot structure, so that the light incident on the light guide plate 130 can be sufficiently emitted by the light. The face 131 is fired. The light incident surface 133 of the light guide plate 13A may have, for example, a V-shaped structure (V-Cut), an S-shaped wave structure, or a surface roughening treatment (not shown), thereby improving the incidence efficiency and optical coupling efficiency of the light. In an embodiment, a reflective sheet (not shown) or a reflective layer (not shown) may be disposed between the light guide plate 130 and the frame 11A to reflect light. Referring to FIG. 2, FIG. 3A, FIG. 3B and FIG. 3C, FIG. 3A to FIG. 3C are partial perspective views of the light source, the light guide plate and the reflection cavity according to the first embodiment of the present invention. The reflective cavity 14 of the embodiment is disposed on one side of the light guide plate 13 , and the reflective cavity 140 can be a long rectangular cylinder or an elongated circular cylinder, which includes the M362423 - the optical port 141, the light exit port 142, and The inner surface of the cavity 143, the outer surface of the reflective cavity 140 outside the light entrance 141 and the light exit 142 is preferably opaque material 144 to prevent light from being exposed, and the medium in the reflective cavity 140 is preferably light transmissive. A medium, such as air, glass, or a highly translucent resin, allows light to be reflected within the reflective cavity 14. The light entrance 141 is formed at one end of the reflective cavity 14〇 to allow the light of the light source 120 to be incident on the reflective cavity 14〇. The light exit opening 142 is formed on one side of the reflective cavity 14 , and faces the light incident surface 133 of the light guide plate 13 用以 to allow light reflected in the reflective cavity 14 可 to be emitted _ in the light guide plate 130 The opening shape of the light exit opening 142 may be any geometric shape, such as a circular shape (as shown in FIG. 3A), a triangular shape (as shown in FIG. 3B), a rectangular shape (as shown in FIG. 3C), or a circular shape. In this embodiment, the reflective cavity 14 is provided with a plurality of light exit openings 142 disposed on one side of the reflective cavity 14 以 to emit light in the light guide plate 130. The material of the inner layer 143 of the cavity is, for example, a high reflectivity material or a phosphor material, which is formed on the inner sidewall of the reflective cavity 14 , and does not cover the exposed light entrance 141 and the light output σ 142 ′ where the high reflectivity The material may form a reflective sheet or a reflective coating, such as silver, inscription, gold, complex, copper, indium, antimony, nickel, germanium, germanium, antimony, tin, button, tungsten, manganese, above A sound alloy, or a yellowing and hot white reflective paint (such as titanium dioxide) for reflecting light within the reflective cavity 140. Although the cavity is slidable... when it is a phosphor material, the light emitted by the light source 12 may be visible or non-visible (preferably ultraviolet light) to excite the light material to emit fluorescence 'and can be reflected Reflection occurs within the cavity 140. - As shown in Fig. 2, in the present embodiment, the reflective cavity 14_^ = the hollow casing of the glue ^ at this time, the medium in the reflection cavity i4Q is (4) the empty jump, and the human light port 141 and The light exit opening 142 can be formed on the reflective cavity 14 by using a punch or a pattern, and the inner side layer (4) of the cavity can be formed on the inner side wall of the _M362423. In one embodiment, the medium in the reflective cavity 140 is, for example, glass or a highly translucent resin. In this case, a cavity/side layer 143' may be formed on the cylinder of the glass or the translucent resin and exposed. The optical port 141 and the light exit port 142, and then, the opaque material 144 is formed (e.g., coated) on the cavity-side layer 143, thereby forming the reflective cavity 140. It is noted that, as shown in Fig. 2, The reflective cavity 14 of the present embodiment is preferably an elongated cylinder having a peripheral side surface and an opposite end surface, the area of the end surface being smaller than the area of the side surface. The light guide plate 130 is disposed on one side (one side) of the peripheral surface of the elongated reflective cavity 140, and the light source 12A and the diffuser plate 15 are disposed on one of the opposite end faces of the reflective cavity 140 (one end). Referring to FIG. 2, FIG. 4A and FIG. 4B, FIG. 4A and FIG. 4B are schematic side views of a diffusion plate according to a first embodiment of the present invention. The diffusing plate 150 of the present embodiment is configured to diffuse light incident on the reflective cavity 14 , wherein the diffusing plate 15 has a plurality of prisms on the surface of the light inlet 141 (as shown in FIG. 4A ). Or a semi-circular (as shown in Figure 4B) protruding structure to further improve the optical effect. The optical film group 160 of the present embodiment is, for example, a diffusion sheet, a cymbal sheet, an enamel film, or any combination thereof, which is disposed on the light guide plate 13A to improve the light-emitting effect of the light guide plate 130. When the light source 12 of the backlight module 1 is illuminated, the light of the light source 120 can be diffused by the diffuser 150 and incident on the reflective cavity 140 via the light entrance port 41. The light can be continuously reflected in the reflective cavity 14A until the light is emitted from the light exit opening 142 into the light guide plate 13A. Therefore, even if the light source 12 is a light-emitting diode or a laser diode having high directivity, the light emitted therefrom can achieve uniform light mixing effect under continuous reflection in the reflective cavity 140. Furthermore, the backlight module 1 of the present embodiment only needs to provide the light source 12 to the M362423-one end of the reflective cavity 14〇 instead of being disposed on the side of the light guide plate 130, thereby reducing the light source of the backlight module ( The number of LED dies and the cost of installation. Referring to FIG. 5, a partial cross-sectional view of a backlight module according to a second embodiment of the present invention is shown. Compared with the first embodiment, the backlight module of the second embodiment may include a plurality of light sources, two reflective cavity bodies 14a and two diffusion plates respectively disposed on opposite sides of the light guide plate 130, thereby The opposite sides of the light guide plate 13 are used to introduce light. Referring to FIG. 6 ′, a partial front view of a light source, a light guide plate and a reflective cavity according to a third embodiment of the present invention is shown. Compared with the first embodiment, the backlight module of the embodiment can include a plurality of light sources 120b and two diffusion plates 15〇b respectively disposed at opposite ends of the reflective cavity 140b, wherein the light source 12〇b The arrangement position of the diffusion plate 150b is parallel to the light-emitting surface 131 of the light guide plate 13A. At this time, the reflection cavity 140b may be provided with two light entrance ports ι41, which are respectively located at opposite ends of the reflection cavity 140b, thereby allowing light to enter. Referring to FIG. 7 ′, a front view of a light source, a light guide plate and a reflective cavity according to a fourth embodiment of the present invention is shown. Compared with the first embodiment, the reflective cavity 140c of the backlight module of the fourth embodiment is provided with a light exit port 142c, which is, for example, a long rectangle (as shown in FIG. 7) or a long circular shape, and corresponds to The light incident surface 133' of the light guide plate 用以3〇 is used to allow light reflected in the reflective cavity 14〇c to be incident on the light guide plate 130. Referring to FIG. 8A and FIG. 8B, a front view of a light source, a light guide plate and a reflective cavity according to a fifth embodiment of the present invention is shown. Compared with the first embodiment, the light exit i42d of the reflective cavity 140d of the fifth embodiment is more or more than the number of the light source 120 away from the light source 120 (as shown in FIG. 8A) or the open area (as shown in FIG. 8B). The number or the area of the opening near the light source 120, that is, the farther away from the light source 120, the more the number of the light exit ports 142d or the larger the opening area M362423', thereby increasing the reflection cavity 140d. The amount of light emitted away from the light source 120. Since the reflection cavity is just farther away from the light source 12, the light intensity of the light is lower. Therefore, the reflection cavity l4〇d of this embodiment can uniformly light the light intensity, so that the light is evenly distributed and incident. The light panel 13 is further integrated to increase the backlight uniformity of the backlight module. It can be seen from the above embodiments of the present invention that the backlight module of the present invention and the liquid crystal display device thereof can use a light source such as a light emitting diode or a laser diode as a backlight, and can reduce the light source (such as LED crystal). The number of particles) is set, thus reducing the cost of the backlight module. Furthermore, the illumination of the light source can be continuously reflected in the reflective cavity until the light exits the light guide. Therefore, the light source can be uniformly mixed in the reflective cavity and then incident on the light guide plate, thereby greatly improving the backlight uniformity of the backlight module. Although the present invention has been disclosed in the above embodiments, it is not intended to limit the present invention, and any person skilled in the art can make various changes and refinements without departing from the spirit and scope of the present invention. The scope of the application is defined by the scope of the patent application. [Simplified description of the drawings] In order to make the above and other objects, features, advantages and embodiments of the present invention more obvious, the detailed description of the drawings 1 is a partial cross-sectional view showing a liquid crystal display panel and a back module according to a first embodiment of the present invention. Fig. 2 is an exploded perspective view showing the light source, the light guide plate and the reflecting cavity according to the first embodiment of the present invention. 3A-3C are partial front elevational views of a light source, a light guide plate, and a reflective cavity in accordance with a first embodiment of the present invention. M362423 Figure A" Figure 4B is a side elevational view of a diffuser panel according to a first embodiment of the present invention. Figure 5 is a partial cross-sectional view of a backlight module in accordance with a second embodiment of the present invention. A partial front view of a light source, a light guide plate and a reflection cavity according to a third embodiment of the present invention is shown. Fig. 7 is a front elevational view showing a light source, a light guide plate and a reflection cavity according to a fourth embodiment of the present invention. 8A and 8B are front elevational views of a light source, a light guide plate, and a reflective cavity according to a fifth embodiment of the present invention. [Main component symbol description] 100: backlight module 110: frame 120, 120b: light source 130: Light guide plate 131: light-emitting surface 132: light-reflecting surface 133: light-incident surface
140、140a ' 140b、140c、140d :反射腔體 141 :入光口 143 :腔體内側層 150、150b :擴散板 200 .液晶顯示面板 142、142c、142d :出光口 144 :不透光材料 160 :光學膜片組140, 140a '140b, 140c, 140d: reflection cavity 141: light entrance port 143: cavity inner layer 150, 150b: diffusion plate 200. liquid crystal display panel 142, 142c, 142d: light exit port 144: opaque material 160 : Optical film set