M358989 五、新型說明： 【新型所屬之技術領域】 本創作是有關於一種光學元件與光源模組，且特別是 有關於一種導光板（light guide plate )及背光模組（backUght module) ° 【先前技術】 # 隨著平面顯示技術的蓬勃發展’液晶顯示器（liquid crystal display，LCD )已逐漸成為顯示技術的主流，其普遍 地被使用於日常生活當中，並取代了傳統陰極射線管 (cathode ray tube, CRT)。由於液晶顯示器中的液晶面板 不會自行發光，因此需採用背光模組來提供背光源。背光 模組依照發光元件的擺設位置可分為直下式背光模組 (direct type backlight module)與側邊入光式背光模組 (side type backlight module )，其中侧邊入光式背光模組 能夠把來自側面的光導向正面而形成面光源之關鍵因素， * 技祕料料板。 在側邊入光式背光模組中，導光板的入光面通常排列 著複數個發光二極體（light emitting diode，LED)，導光板 的下表面具有複數個稜鏡柱，其中每一稜鏡柱皆具有相同 高度（亦即是每一棱鏡柱皆相同）。因此，來自發光二極 體的光束通過入光面並進入導光板後，因上述棱鏡柱而破 壞光束在導光板内的全反射現象，而使配置於導光板内的 光束得以被導引，並可均勻地由上表面出射而離開導光板。 4 M358989 -1又而5 ’側邊人光式背光模組通常配置—反射片於 導光板的下表面’讀部分通釘表面__光束得以 被反射而再傳遞回導光㈣，藉簡升背光模組的背光亮 度。 & 然而’因下表面具有複數個相同的稜鏡柱，且反射片 通常為軟性材f，，當反射纽置於下表面時，使得 部分的稜鏡柱與反射片接觸，另—部分的稜鏡柱則不與反 射片接觸，其中，稜鏡柱與反射片飾的區域產生沾^與 到傷的問題’而影響反射光束的效果。另外，在棱鏡柱與 反射片沾_區域上則產生白斑或色環的現象，進而影響 背光模組所提供的面光源的均勻度。 【新型内容】 本創作提供-種導光板，其可降低稜鏡柱被到傷的機 率，以及減少與其他光學膜片產生沾粘的問題。 本創作提供一種背光模組’其採用上述導光板而可降 低稜鏡柱與其他光學膜片產生沾粘與刮傷的機率，進而可 k供較均勻的面光.源。 本創作的其他目的和優點可以從本創作所揭露的技 術特徵中得到進一步的了解。 為達上述之一或部份或全部目的或是其他目的，本創 作之一實施例提出一種導光板，適於導引至少一光源所提 供的光束。其包括一透光基板、複數個第—稜鏡柱以及 複數個第二稜鏡柱。透光基板具有一第一表面、一與第一 M358989 表面相對的第二表面以及一連接第一表面與第二表面的入 光面。光源所提供的光束通過入光面而進入導光板，來自 入光面的光束由第二表面出射而離開第二表面。這些第一 棱鏡柱配置於第一表面上，這些第一稜鏡柱沿一第一方向 排列及沿一第二方向延伸’其中第一方向與第二方向實質 上垂直。各第一棱鏡柱在垂直於第一表面的方向上具有一 第一高度’且兩相鄰的這些第一稜鏡柱的各間距是落在 500//m至1500的範圍内。這些第二稜鏡柱配置於第 一表面上’這些第二稜鏡柱至少部份配置於兩相鄰的這些 第一稜鏡柱之間，這些第二稜鏡柱沿第一方向排列及沿第 二方向延伸。此外，各第二稜鏡柱在垂直第一表面的方向 上具有一第二高度，第一高度大於第二高度。 本創作之另一實施例提出一種背光模組，其包括至少 一光源、一導光板以及至少一光學膜片。光源適於提供一 光束。導光板適於導引光源所提供的光束。導光板包括一 透光基板、複數個第一稜鏡柱以及複數個第二稜鏡柱。透 光基板具有一第一表面、一與第一表面相對的第二表面以 及一連接第一表面與第二表面的入光面。光源所提供的光 束通過入光面而進入導光板，來自入光面的光束由第二表 面出射而離開第二表面。這些第一稜鏡柱配置於第一表面 上，這些第一稜鏡柱沿一第一方向排列及沿—第二方向延 伸，其中第一方向與第二方向實質上垂直。各第一稜鏡柱 在垂直於第一表面的方向上具有一第一高度，且兩相鄰的 這些第一稜鏡柱的各間距是落在500从m至15〇〇 M m的範 6 M358989 圍内。這些第二稜鏡柱配置於第一表面上，這些第二稜鏡 柱至少部份配置於兩相鄰的這些第一稜鏡柱之間，這些第 二稜鏡柱沿第一方向排列及沿第二方向延伸。此外，各第 二稜鏡柱在垂直第一表面的方向上具有一第二高度，第一 高度大於第二高度。光學膜片配置於第二表面之上。 在本創作之一實施例中，第二方向實質上垂直於入光 面。 在本創作之一實施例中，第一高度與第二高度的差值 是洛在l/zm至5//m之間。 在本創作之一實施例中，兩相鄰的這些第一稜鏡柱的 這些間距可為彼此相同。 在本創作之一實施例中，兩相鄰的這些第一稜鏡柱的 這些間距至少部分不同。 在本創作之一實施例中’透光基板、第一稜鏡柱與第 一棱鏡柱可為一體成型。 在本創作之一實施例中’透光基板、第一稜鏡柱與第 二稜鏡柱可為各自成型。 在本創作之一實施例中，第一稜鏡柱與第二稜鏡柱可 為二角柱狀棱鏡。 在本創作之一實施例中，第二表面為一霧面。 在本創作之一實施例中，光學膜片為一光學擴散片與 一逆棱鏡片至少其中之一。 在本創作之一實施例中’背光模組更包括一反射片， 配置於第一表面之上。 7 M358989 基於上述，由於本創作之實施例的導光板在垂直於第 一表面的方向上具有不同高度的第一稜鏡柱與第二稜鏡 柱，其中第一稜鏡柱的高度大於第二稜鏡柱的高度，而可 降低第二稜鏡柱被刮傷的機率。另外，若配置一反射片於 導光板的第一表面之上，藉以提高導光板所提供的面光源 的亮度時，除了可藉由上述結構而避免第二稜鏡柱與反射 片之間產生刮傷或沾枯的問題外，更因兩相鄰的這此第一 • 稜鏡柱的各間距是落在5〇〇//m至1500的範圍内，而 可減少如白斑或色環等光學現象的產生。因此，採用上述 之導光板的背光模組則可提供較均勻的面光源。 為讓本創作之上述特徵和優點能更明顯易懂，下文特 舉實施例’並配合所附圖式作詳細說明如下。 【實施方式】 偷3各^施例的說明是參考附加的圖*，用以例示本 施之特定實施例。有關本創作之前述及其他 中Γ與功效’在以下配合參考圖式之實施例的 :二中:將可清楚的呈」^ 々、 卜」、刖」、「後」、「左 、「， 等，僅疋參考附加圖式的方向。因此 1 用來說明1翻來_本創作。用的方向用垂是 圖2: f本創作之—實施例之背光模組的剖面示奇圖， 圖一為圖1所緣示之導光板的立體示意圖 緣示之背光模組的立體示意圖’圖4為圖3之背= 8 M358989 A-A剖線所繪示之背光模組的剖面示意圖。請同時參考圖 1與圖3，本實施例之背光模組1〇〇包括至少一光源11()、 一 V光板120以及至少一光學膜片13〇。光源ι1〇適於提 供一光束112。導光板130適於導引光源11〇所提供的光 束112。在本實施例中，光源11〇，例如可為複數個發光二 極體（light emitting diode，LED)。在其他實施例中，光源 Π0 ’例如可為冷陰極燈管（c〇id Cathode Fluorescence Lamp ’ CCFL )，或其他適當的光源。 請參考圖1與圖2’導光板120包括一透光基板122、 複數個第一稜鏡柱124以及複數個第二稜鏡柱丨26。透光 基板122具有一第一表面122a、一與第一表面122a相對 的第二表面122b以及一連接第一表面i22a與第二表面 122b的入光面122c。光源110所提供的光束H2通過入光 面122c而進入導光板120 ’來自入光面122c的光束112 由第二表面122b出射而離開第二表面i22b。在本實施例 中’透光基板122的材質例如是採用聚碳酸酯（pc)或壓 克力（PMMA)之類的材質。在其他實施例中，透光基板 122的材質例如是採用其他透光材質。 如圖2所示，第一稜鏡柱124配置於透明基板122的 第一表面122a上，並沿一第一方向pi排列及沿一第二方 向P2延伸，其中第一方向P1與第二方向P2實質上垂直。 在本實施例中’第二方向P2實質上垂直於入光面122c。 另外，如圖2與圖4所示，各第一稜鏡柱124在垂直於第 一表面122a的方向上具有一第一高度H1，且兩相鄰的這 9 M358989 些第一稜鏡柱124的各間是落在5〇〇ym至15〇〇^m 的範圍内。在本實施例中，_鄰的這些第—稜鏡柱124 的這些間距m至少部分不同，也就找，兩相鄰的第一 棱鏡柱124的這些間距D1可以是採用不規則間隔的排列 方式。在另—實關巾，兩相鄰的這些第-稜鏡柱124的 遣些間距D1也可以S彼此相同，亦即是，兩相鄰的第一 稜鏡柱124的這些間距Dl可以是採用規則間隔的排列方 式。在另一實施例中’若兩相鄰的第一稜嶽主124的這些 間距D1採用規關隔的排列方式，間距D1可以是採用 8〇〇/zm的設計。當，然’兩相鄰的這些第一棱鏡柱m的各 =距D1可依使用者的需求而^ ’上述僅為舉例說明。值 知'一提的是’無論是採用規則或不規則的間隔，其間距1)1 數值落在500/m至1’_的範圍内皆為本創作所欲保 護的範圍。 如圖2所示，第二稜鏡柱126配置於第一表面122a 上，第二稜鏡柱126至少部份配置於兩相鄰的這些第一稜 鏡柱124之間，並沿第一方向P1排列及沿第二方向p2延 伸。此外，如圖4所示，各第二稜鏡柱126在垂直第一表 面122a的方向上具有一第二高度H2，且第一高度hi大 於第二高度H2。在本實施例中，第一高度111與第二高度 H2的差值是落在1//：11至5#m之間。在本實施例中，第 —稜鏡柱124與第二稜鏡柱120例如可為三角稜鏡柱。在 其他未繪示的實施例中，第一稜鏡柱124與第二稜鏡柱126 例如可為其他形狀的稜鏡柱。 10 M358989 在一實施例中’透光基板122、第一稜鏡柱124與第 二稜鏡柱126可以是各自成型或一體成型。詳細而言，採 用各自成型的方式製作導光板120,例如是先分別製作透 光基板122、第一稜鏡柱124以及第二稜鏡柱126的結構， 接著再將三者結合而形成如圖2所示之導光板12〇。而採 用一體成型的方式製作導光板120時，則是先製作透光基 板122 ’而後再使用沖模或印刷的技術，在透光基板122 的第一表面122a上直接形成第一棱鏡柱124與第二稜鏡枉 126。 如圖1所示，在本實施例中，為了提高光束U2的利 用性及k升jg光模組1 〇〇所提供面光源的均勻性與光強 度，第一表面122a上配置有一反射片14〇，以將出射於第 一表面122a的部分的光束112反射回導光板12〇内，而使 得大多數的光束112可由第二表面122b出射。在另一實施 例中，反射片140之材質例如可為軟性材質。另外，為了 使光束112可較容易出射於第二表面122b，在本實施例中 第二表面122b例如可為一霧面結構以破壞光束112在第二 表面122b的全反射。在另一實施例中，可使用噴砂的方式 在第二表面122b形成霧面結構。 在本實施例中，由於第—稜鏡柱124的高度Hi大於 第二稜鏡柱的高度H2’因此，反射片14〇配置於第一表面 122a時，第一棱鏡柱124與反射片14〇接觸，第二稜鏡柱 126不與反射片接觸’且兩相鄰的這些第一稜鏡柱μ的 各間距D1疋落在5〇〇#m至的範圍内。進而可 M358989 減少棱鏡柱與反射片140接觸時被到傷的機率，及可降低 棱鏡柱與反射片140沾枯的面積。再者，若適當調整相鄰 的兩第-稜鏡柱124之間的各間距m，亦可解 與反射片沾枯的區域上產生白斑或色環的現象，、從而可使 背光模組100提供較均勻的的面光源。 斤如圖1與圖3所示，光學膜片13〇配置於導光板 的第-表面122b之上’以使背光模組1〇〇可提供較為均勻 φ 的面光源。在本實施例中，光學膜片130可為一逆稜鏡片 132與一光學擴散片134的至少其中之一。 如圖3與圖4所示，在本實施例中，逆稜鏡片132配 置於光學擴散片134與導光板120之間。詳細而言，逆稜 鏡片132具有複數個第三稜鏡柱132&，其甲這些第三稜鏡 柱132a沿一第二方向P2排列及沿一第一方向P1延伸， 其中第一方向P1與第二方向P2實質上垂直。如此一來， 來自第二表面122b的光束112被逆稜鏡片132所會聚，而 可使得入射於光學擴散片134的光束112較多，進而提高 •背光模組100的整體亮度。另外，光學擴散片134的設置 亦可提升背光模組100所提供面光源的均勻度。 綜上所述，在本創作之實施例的導光板中，由於各第 一稜鏡柱與各第二稜鏡柱在垂直於第一表面的方向上具有 不同高度，其中各第一稜鏡柱的高度大於各第二稜鏡柱的 高度’因而可降低稜鏡柱被刮傷的機率◦另外，若配置一 反射片於導光板的第一表面之上藉以提高導光板所提供的 面光源的亮度時，因上述結構而可降低稜鏡柱與反射片之 12 M358989 柱的各門距^ 因兩相㈣這些第一稜鏡 拄的各間距疋洛在500/am 少如白斑或色㈣pw #的耗圍内，而可減 導m2!? 的產生。換言之，採用上述之 先板的月光模組可提供較均㈣面光源。 太：然，已以實施例揭露如上，然其並非用以限定 太巍j何所4技術領域巾具有通常知識者，在不脫離 =1ί和範_，#可作鍵之更動與潤飾，故本 之呆濩範圍當視後附之申請專利範圍所界定者為 另外本創麵任—實補或_請專職圍不須達成本創作 所揭露之全部目的或優點或特點。此外，摘 僅是^辅助專敎件搜尋之用，並_來_本創;^ 權利範圍。 【圖式簡單說明】 圖1為本創作之一實施例之背光模組的剖面示意圖。 圖2為圖1所繪示之導光板的立體示意圖。 圖3則為本創作之一實施例之背光模組的立體示音、 圖。 心 圖4為圖3之背光椒組沿Α-Α’剖線所纟會示之背光模組 的剖面示意圖。 【主要元件符號說明】 100 :背光模組 11〇 ·光源 13 M358989 112 :光束 120 :導光板 122 :透光基板 122a :第一表面 122b :第二表面 122c :入光面 124:第一稜鏡柱 126 :第二稜鏡柱 130 :光學膜片 132 :逆稜鏡片 132a :第三稜鏡柱 134 :擴散片 140 :反射片 P1 :第一方向 P2 :第二方向 H1 :第一高度 • H2 :第二高度 D1 :間距M358989 V. New description: [New technical field] This creation is about an optical component and light source module, and especially related to a light guide plate and a backlight module (backUght module) ° Technology] # With the development of flat display technology' liquid crystal display (LCD) has gradually become the mainstream of display technology, which is commonly used in daily life, and replaces the traditional cathode ray tube (cathode ray tube) , CRT). Since the liquid crystal panel in the liquid crystal display does not emit light by itself, a backlight module is required to provide a backlight. The backlight module can be divided into a direct type backlight module and a side type backlight module according to the position of the light emitting device, wherein the side light-inducing backlight module can The light from the side is directed to the front side to form the key factor of the surface light source, * the technical material board. In the side-lit backlight module, the light-incident surface of the light guide plate is usually arranged with a plurality of light emitting diodes (LEDs), and the lower surface of the light guide plate has a plurality of columns, wherein each edge The mirror columns all have the same height (that is, each prism column is the same). Therefore, after the light beam from the light-emitting diode passes through the light incident surface and enters the light guide plate, the total reflection phenomenon of the light beam in the light guide plate is destroyed by the prism column, and the light beam disposed in the light guide plate is guided, and It can be uniformly emitted from the upper surface and left the light guide plate. 4 M358989 -1 and 5 'side RGB backlight module is usually configured - the reflection sheet is on the lower surface of the light guide plate 'read part of the nail surface _ _ beam can be reflected and then transmitted back to the light guide (4), by simple Backlight brightness of the backlight module. & However, 'because the lower surface has a plurality of identical masts, and the reflective sheet is usually a soft material f, when the reflective bump is placed on the lower surface, the partial mast is in contact with the reflective sheet, and the other portion is The mast is not in contact with the reflective sheet, and the region where the mast and the reflective sheet are decorated has a problem of sticking and hurting, and affecting the effect of the reflected beam. In addition, white spots or color circles are generated on the prism column and the reflective sheet, which affects the uniformity of the surface light source provided by the backlight module. [New Content] This creation provides a kind of light guide plate that reduces the chance of the column being injured and reduces the problem of sticking to other optical films. The present invention provides a backlight module which uses the above-mentioned light guide plate to reduce the probability of sticking and scratching of the mast and other optical films, thereby providing a more uniform surface light source. Other objects and advantages of the present work can be further understood from the technical features disclosed in this creation. In order to achieve one or a portion or all of the above or other objects, an embodiment of the present invention provides a light guide plate adapted to guide a light beam provided by at least one light source. The utility model comprises a transparent substrate, a plurality of first masts and a plurality of second masts. The light transmissive substrate has a first surface, a second surface opposite the surface of the first M358989, and a light incident surface connecting the first surface and the second surface. The light beam provided by the light source enters the light guide plate through the light incident surface, and the light beam from the light incident surface exits the second surface and exits the second surface. The first prism columns are disposed on the first surface, and the first masts are arranged along a first direction and extend in a second direction, wherein the first direction is substantially perpendicular to the second direction. Each of the first prism posts has a first height ' in a direction perpendicular to the first surface and each of the adjacent first masts has a pitch ranging from 500//m to 1500. The second masts are disposed on the first surface. The second masts are at least partially disposed between the two adjacent first masts. The second masts are arranged along the first direction and along the first masts. The second direction extends. Further, each of the second masts has a second height in a direction perpendicular to the first surface, the first height being greater than the second height. Another embodiment of the present invention provides a backlight module including at least one light source, a light guide plate, and at least one optical film. The light source is adapted to provide a beam of light. The light guide plate is adapted to guide the light beam provided by the light source. The light guide plate includes a light transmissive substrate, a plurality of first masts, and a plurality of second masts. The light transmissive substrate has a first surface, a second surface opposite the first surface, and a light incident surface connecting the first surface and the second surface. The light beam provided by the light source enters the light guide plate through the light incident surface, and the light beam from the light incident surface exits the second surface and exits the second surface. The first masts are disposed on the first surface, the first masts are arranged along a first direction and extend in a second direction, wherein the first direction is substantially perpendicular to the second direction. Each of the first masts has a first height in a direction perpendicular to the first surface, and each of the two adjacent first masts has a pitch of 500 from m to 15 〇〇M m M358989 inside. The second masts are disposed on the first surface, and the second masts are at least partially disposed between the two adjacent first masts, and the second masts are arranged along the first direction and along the second masts The second direction extends. Further, each of the second masts has a second height in a direction perpendicular to the first surface, the first height being greater than the second height. The optical film is disposed over the second surface. In one embodiment of the present invention, the second direction is substantially perpendicular to the light incident surface. In one embodiment of the present invention, the difference between the first height and the second height is between 1/zm and 5/m. In one embodiment of the present invention, the spacing of the two adjacent first masts may be the same as each other. In one embodiment of the present invention, the spacing of the two adjacent first masts is at least partially different. In one embodiment of the present invention, the light transmissive substrate, the first mast and the first prism post may be integrally formed. In one embodiment of the present invention, the light transmissive substrate, the first mast and the second mast may be formed separately. In an embodiment of the present invention, the first mast and the second mast may be a two-corner prism. In one embodiment of the present invention, the second surface is a matte surface. In one embodiment of the present invention, the optical film is at least one of an optical diffusion sheet and a reverse prism sheet. In an embodiment of the present invention, the backlight module further includes a reflective sheet disposed on the first surface. 7 M358989 Based on the above, since the light guide plate of the embodiment of the present invention has different heights of the first mast and the second mast in a direction perpendicular to the first surface, wherein the height of the first mast is greater than the second The height of the mast can reduce the chance of the second mast being scratched. In addition, if a reflective sheet is disposed on the first surface of the light guide plate to improve the brightness of the surface light source provided by the light guide plate, the scraping between the second mast and the reflective sheet can be avoided by the above structure. In addition to the problem of injury or staining, the distance between the two adjacent first masts falls within the range of 5 〇〇//m to 1500, and optical such as white spots or color rings can be reduced. The phenomenon is produced. Therefore, the backlight module using the above light guide plate can provide a relatively uniform surface light source. To make the above-described features and advantages of the present invention more comprehensible, the following detailed description is made in conjunction with the accompanying drawings. [Embodiment] The description of the embodiment is referred to the attached figure* for illustrating a specific embodiment of the present embodiment. The foregoing and other related features and efficiencies of the present invention are as follows: In the following, the following examples of the reference drawings: 2: will be clearly expressed as "^ 々, 卜", 刖", "后", "left," Etc., only refer to the direction of the additional schema. Therefore, 1 is used to illustrate the translation of the original. The direction used is as shown in Figure 2: f. The creation of the backlight module of the embodiment is shown in the figure. FIG. 4 is a schematic cross-sectional view of the backlight module shown in the rear view of FIG. 3 and the rear view of the light guide plate shown in FIG. 1 and 3, the backlight module 1A of the present embodiment includes at least one light source 11(), a V-light panel 120, and at least one optical film 13A. The light source ι1 is adapted to provide a light beam 112. The light guide plate 130 It is suitable for guiding the light beam 112 provided by the light source 11 。 In the embodiment, the light source 11 〇 can be, for example, a plurality of light emitting diodes (LEDs). In other embodiments, the light source Π 0 ' Can be a cold cathode lamp (c〇id Cathode Fluorescence Lamp ' CCFL ), or other The light guide plate 120 includes a transparent substrate 122, a plurality of first masts 124, and a plurality of second masts 26. The transparent substrate 122 has a first surface. The second surface 122b opposite to the first surface 122a and the light incident surface 122c connecting the first surface i22a and the second surface 122b. The light beam H2 provided by the light source 110 enters the light guide plate 120 through the light incident surface 122c. The light beam 112 from the light incident surface 122c is emitted from the second surface 122b away from the second surface i22b. In the embodiment, the material of the transparent substrate 122 is, for example, polycarbonate (pc) or acrylic (PMMA). In other embodiments, the material of the transparent substrate 122 is made of other light transmissive materials. As shown in FIG. 2, the first mast 124 is disposed on the first surface 122a of the transparent substrate 122 and along the edge. A first direction pi is arranged and extends along a second direction P2, wherein the first direction P1 is substantially perpendicular to the second direction P2. In the embodiment, the 'second direction P2 is substantially perpendicular to the light incident surface 122c. As shown in FIG. 2 and FIG. 4, each first mast 124 is at There is a first height H1 in a direction perpendicular to the first surface 122a, and the two adjacent first masts 124 of the 9 M358989 fall within a range of 5 〇〇 ym to 15 〇〇 ^ m. In the present embodiment, the spacings m of the first masts 124 of the adjacent sub-column 124 are at least partially different, that is, the spacing D1 of the two adjacent first prism pillars 124 may be arranged in an irregular interval. In another mode, the spacings D1 of the two adjacent first masts 124 may be the same as each other, that is, the spacing D1 of the two adjacent first masts 124 may be It is arranged in a regular interval. In another embodiment, if the spacings D1 of the two adjacent first ridges 124 are arranged in a spaced apart manner, the spacing D1 may be a design of 8 〇〇/zm. When, respectively, the respective distances D1 of the two adjacent first prism columns m can be determined according to the needs of the user. Values know that 'whether it is a rule or an irregular interval, the spacing 1)1 value falls within the range of 500/m to 1'_, which is the scope of the creative protection. As shown in FIG. 2, the second mast 126 is disposed on the first surface 122a, and the second mast 126 is at least partially disposed between the two adjacent first masts 124 and in the first direction. P1 is arranged and extends in the second direction p2. Further, as shown in Fig. 4, each of the second masts 126 has a second height H2 in the direction perpendicular to the first surface 122a, and the first height hi is greater than the second height H2. In the present embodiment, the difference between the first height 111 and the second height H2 falls between 1//: 11 and 5 #m. In this embodiment, the first mast 124 and the second mast 120 may be, for example, a triangular mast. In other embodiments not shown, the first mast 124 and the second mast 126 may be, for example, other shaped masts. 10 M358989 In one embodiment, the light transmissive substrate 122, the first mast 124, and the second mast 126 may be each formed or integrally formed. Specifically, the light guide plate 120 is formed by the respective molding methods. For example, the structures of the light-transmitting substrate 122, the first mast 124, and the second mast 126 are separately formed, and then the three are combined to form a figure. The light guide plate 12 shown in FIG. When the light guide plate 120 is integrally formed, the first prism column 124 and the first surface 122a are directly formed on the first surface 122a of the transparent substrate 122 by first forming the transparent substrate 122' and then using a die or printing technique. Second 126. As shown in FIG. 1, in the embodiment, in order to improve the usability of the light beam U2 and the uniformity and light intensity of the surface light source provided by the optical module 1 ,, a reflective sheet 14 is disposed on the first surface 122a. That is, the light beam 112 that is emitted from the portion of the first surface 122a is reflected back into the light guide plate 12A such that most of the light beam 112 can be emitted by the second surface 122b. In another embodiment, the material of the reflection sheet 140 may be, for example, a soft material. In addition, in order to make the light beam 112 relatively easy to exit the second surface 122b, the second surface 122b may be, for example, a matte structure in this embodiment to destroy the total reflection of the light beam 112 on the second surface 122b. In another embodiment, a matte structure may be formed on the second surface 122b using sand blasting. In this embodiment, since the height Hi of the first mast 124 is greater than the height H2 of the second mast, the first prism post 124 and the reflective sheet 14 are disposed when the reflective sheet 14 is disposed on the first surface 122a. In contact, the second mast 126 is not in contact with the reflective sheet and the respective distances D1 of the two adjacent first masts μ are within a range of 5 〇〇 #m. Further, M358989 can reduce the probability of being injured when the prism column is in contact with the reflection sheet 140, and can reduce the area where the prism column and the reflection sheet 140 are wetted. Furthermore, if the pitch m between the adjacent two first-columns 124 is appropriately adjusted, a phenomenon of white spots or color circles may be generated in a region where the reflective sheet is wetted, thereby enabling the backlight module 100. Provide a more uniform surface source. As shown in Fig. 1 and Fig. 3, the optical film 13 is disposed above the first surface 122b of the light guide plate so that the backlight module 1 can provide a relatively uniform surface light source of φ. In this embodiment, the optical film 130 can be at least one of a reverse film 132 and an optical diffusion sheet 134. As shown in FIG. 3 and FIG. 4, in the present embodiment, the reverse gusset 132 is disposed between the optical diffusion sheet 134 and the light guide plate 120. In detail, the reverse diaphragm 132 has a plurality of third masts 132 & a, the third masts 132a are arranged along a second direction P2 and extend along a first direction P1, wherein the first direction P1 and The second direction P2 is substantially vertical. As a result, the light beam 112 from the second surface 122b is concentrated by the backing plate 132, so that the light beam 112 incident on the optical diffusion sheet 134 is increased, thereby improving the overall brightness of the backlight module 100. In addition, the arrangement of the optical diffuser 134 can also improve the uniformity of the surface light source provided by the backlight module 100. In summary, in the light guide plate of the embodiment of the present invention, each of the first mast and each of the second masts have different heights in a direction perpendicular to the first surface, wherein each of the first masts The height of the second mast is greater than the height of each of the second masts. Thus, the probability of the mast being scratched is reduced. In addition, if a reflective sheet is disposed on the first surface of the light guide plate, the surface light source provided by the light guide plate is raised. In the case of brightness, due to the above structure, the distance between the legs of the 12 M358989 column of the mast and the reflection sheet can be reduced. 2. Because of the two phases (four), the spacing of the first turns is less than 500/am, such as white spots or colors (four) pw # The consumption of the m2!? can be reduced. In other words, the moonlight module using the above-mentioned first board can provide a relatively uniform (four) surface light source. Too: However, the above has been disclosed in the above embodiments, but it is not intended to limit the general knowledge of the technical field of the 4th technical field, and it can be used as a key to the change and retouching. The scope of the stagnation is defined as the scope of the patent application, which is defined by the scope of the patent application. It is not necessary to achieve all the objectives or advantages or features disclosed in this creation. In addition, the excerpt is only for the use of auxiliary accessories search, and _ to _ this creation; ^ the scope of rights. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic cross-sectional view of a backlight module according to an embodiment of the present invention. 2 is a perspective view of the light guide plate illustrated in FIG. 1 . FIG. 3 is a stereoscopic view and a diagram of a backlight module according to an embodiment of the present invention. Figure 4 is a schematic cross-sectional view of the backlight module of Figure 3 in the back-and-forth section of the back-and-forth. [Main component symbol description] 100: backlight module 11 〇 light source 13 M358989 112: light beam 120: light guide plate 122: light-transmitting substrate 122a: first surface 122b: second surface 122c: light-incident surface 124: first 稜鏡Column 126: second mast 130: optical diaphragm 132: reverse diaphragm 132a: third mast 134: diffuser 140: reflective sheet P1: first direction P2: second direction H1: first height • H2 : second height D1 : spacing