201226994 六、發明說明： 【發明所屬之技術領域】 本發明關於一種擴散片，尤指一種利用表面粗糙度使光線產生 霧化效果之擴散片及應用此擴散片之背光模組。 【先前技術】 由於液晶顯示裝置具有薄型化、輕量化、低耗電量、無輻射污 柒且能與半導體製程技術相容等優點，液晶顯示裝置已被廣泛應用 於各式各樣的電子裝置中，例如筆記型電腦、行動電話、數位相機、 個人數位助料。液㉟齡裝置係㈣背賴祕供練至顯示面 板上，以糾晝面。-躺言’背光模具有H组合以及 光學膜片組合。光源組合用以提供光線，而光學膜片組合則用以 改善光線之鮮特性。光學則組合所包含之絲則例如為稜鏡 片、擴散片等。 s月參閱第1圖’第1圖為先前技術之擴散片1〇的示意圖。如第 1圖所不’擴散片10係由基材(例如，聚乙騎笨二曱酸醋拖T) 以及塗佈於基材上下表面之擴散層12G、14G組成。賴技術係 於擴政層120、140中摻雜多個珠粒16〇 (例如，聚甲基丙婦酸甲酉旨 PMMA)，以使通過擴散片1〇的光線產生霧化效果。然而，當裝設 有擴散片ίο之背光模組或顯示裝置被搖晃或振動時，擴散層12〇、 140中的珠粒160容易脫落或刮傷基材1〇〇上下表面，或當擴散片 201226994 10運用於顯示裝置時’會刮傷相鄰喊學片或物件，進而於顯示晝 面出現干涉條紋現象（mura)。此外，捧雜多個珠粒⑽之擴散片 10也會影響齡裝置之品位紐，使得使时峨賞舒適度降低， 易從顯示裝置觀察到由珠粒16G所造成之不明圖案。 【發明内容】 本發明的目的之-在於提供一種擴散片及應用此擴散片之背光 模組，以解決上述問題。 根據-實施例，本發明之擴散片包含一基材、一第一擴散層以 及-第二擴㈣。第-擴散層設置於基材上，且第二擴散層設置於 第-擴散層上。第-擴散層包含—第—表面結構，且第—表面結構 (peakc〇untvalueofr〇ughnesS5Rpc)o ^ 二擴散層包含-第二表面結構以及—第三表面結構其中第二表面 結構與第Z表面結構分細彡成於第二擴散層之蝴二側，且第三表 面結構與第-表面結構重合。第二表面結構具有—第二粗縫度峰數 值’且第二《植峰數值大於或等於第—秘度峰數值。 根據另-實關，本發明之背光·包含—光學則組合以及 -光源組合。光學膜片組合包含—第—擴散片，且第—擴散片位於 光學膜片組合之最外側。第-擴散片包含—基材、—第—擴散層以 及-第二擴散層。第-擴散層設置於基材上，且第二擴散層設^ 第-擴散層上。第-擴散層包含-第—表面結構，且第一表面結構 201226994 具有-第-祕度峰數值。第二擴散層包含—第二表面結構以及一 第三表面結構’其中第二表面結構與第三表面結構分卿成於第二 擴散層之蝴二側’且第三表面結構與第-表聽構重合。第二表 面結構具有—第二_度峰數值，且第二_度峰數值大於或等於 第一粗链度峰數值。 知上所述’本發明係於不同的擴散層分別形成具有不同或相同 的粗k度峰數值之表面結構，以使通職散⑽光線產生霧化效 果。因此’本發明之擴散片不需於擴散層巾摻雜珠粒，進而避免珠 粒脫落或到傷基材表面等問題。 關於本發明之優點與精神可以藉由以下的發明詳述及所附圖式 得到進一步的瞭解。 【實施方式】 請參閱第2圖’第2圖為根據本發明一實施例之背光模組3的 示意圖。如第2圖所示，背光模組3包含一光學膜片組合3〇以及一 光源組合32’其中光學膜片組合3〇設置於光源組合32上。背光模 組3可應用於液晶顯示器中。光學膜片組合3〇包含一第一擴散片 300、一第一稜鏡片302、一第二稜鏡片3〇4以及一第二擴散片306。 第一複鏡片302設置於第一擴散片3〇〇下，第二稜鏡片3〇4設置於 第一棱鏡片302下，且第二擴散片3〇6設置於第二稜鏡片3〇4下。 換言之，第一擴散片300係位於光學膜片組合3〇之最外側。 201226994 於此實施例中，背光模組3係為一側光式背光模組。因此’光 源組合32包含一導光板320、一反射片322、一光源324以及一反 射板326。導光板320設置於光學膜片組合30之第二擴散片306下’ 反射片322設置於導光板320下，光源324設置於導光板320之一 側，且反射板326設置於光源324周圍。於實際應用中，光源324 可為冷陰極管（cold cathode fluorescent lamp, CCFL)或發光二極體 (light emitting diode，LED )。需說明的是，側光式背光模組之作用 原理為習知技藝之人所熟知，在此不再贅述。 凊參閱第3圖以及第4圖’第3圖為第2圖中的第一擴散片300 的不意圖，第4圖為第3圖中的第—擴散片的爆炸圖。如第3 圖與第4圖所示，第—擴散片包含一基材3000、一第一擴散層 3002以及一第201226994 VI. Description of the Invention: [Technical Field] The present invention relates to a diffusion sheet, and more particularly to a diffusion sheet which utilizes surface roughness to impart a fogging effect to light and a backlight module using the same. [Prior Art] Since liquid crystal display devices have advantages of thinness, light weight, low power consumption, no radiation pollution, and compatibility with semiconductor process technology, liquid crystal display devices have been widely used in various electronic devices. Medium, such as notebook computers, mobile phones, digital cameras, personal digital helpers. The liquid 35-year-old device system (4) is backed up to the display panel to correct the surface. - Lyrics' Backlight molds have an H combination and an optical diaphragm combination. The combination of light sources provides light and the optical diaphragm combination improves the light characteristics. The optical inclusions may be, for example, a ruthenium sheet, a diffusion sheet or the like. Referring to Figure 1 for the month of s, Figure 1 is a schematic view of a diffusion sheet of the prior art. As shown in Fig. 1, the diffusion sheet 10 is composed of a substrate (for example, a polyethylene t-buckle tart) and a diffusion layer 12G, 14G coated on the upper and lower surfaces of the substrate. Lai technology is doped with a plurality of beads 16 (e.g., polymethyl methacrylate for PMMA) in the expansion layers 120, 140 to produce a fogging effect through the light of the diffusion sheet. However, when the backlight module or the display device provided with the diffusion sheet is shaken or vibrated, the beads 160 in the diffusion layers 12, 140 are liable to fall off or scratch the upper and lower surfaces of the substrate 1 or as a diffusion sheet. When 201226994 10 is used in the display device, it will scratch the adjacent screaming film or object, and the interference smear will appear on the display surface. In addition, the diffusion sheet 10 holding the plurality of beads (10) also affects the grade of the aged device, so that the comfort of the time is reduced, and an unidentified pattern caused by the beads 16G is easily observed from the display device. SUMMARY OF THE INVENTION An object of the present invention is to provide a diffusion sheet and a backlight module using the same to solve the above problems. According to an embodiment, the diffusion sheet of the present invention comprises a substrate, a first diffusion layer, and a second diffusion (four). The first diffusion layer is disposed on the substrate, and the second diffusion layer is disposed on the first diffusion layer. The first diffusion layer includes a first surface structure, and the first surface structure (peakc〇untvalueofr〇ughnesS5Rpc)o ^ the second diffusion layer includes a second surface structure and a third surface structure, wherein the second surface structure and the Zth surface structure The fine surface is divided into two sides of the second diffusion layer, and the third surface structure coincides with the first surface structure. The second surface structure has a second coarse slit peak value ' and the second "plant peak value is greater than or equal to the first secret peak value. According to another embodiment, the backlight of the present invention includes an optical combination and a light source combination. The optical film assembly includes a first diffusion sheet, and the first diffusion sheet is located at the outermost side of the optical film assembly. The first diffusion sheet includes a substrate, a first diffusion layer, and a second diffusion layer. The first diffusion layer is disposed on the substrate, and the second diffusion layer is disposed on the first diffusion layer. The first diffusion layer includes a -first surface structure, and the first surface structure 201226994 has a -first-precision peak value. The second diffusion layer includes a second surface structure and a third surface structure 'where the second surface structure and the third surface structure are separated from the two sides of the second diffusion layer' and the third surface structure and the first surface are heard Structure coincidence. The second surface structure has a second _ degree peak value and the second _ degree peak value is greater than or equal to the first thick chain peak value. It is to be understood that the present invention is based on the fact that different diffusion layers respectively form surface structures having different or identical values of coarse k-degree peaks to cause atomization effects of the active (10) light. Therefore, the diffusion sheet of the present invention does not need to be doped with beads in the diffusion layer, thereby avoiding problems such as falling off of the beads or damage to the surface of the substrate. The advantages and spirit of the present invention will be further understood from the following detailed description of the invention. [Embodiment] FIG. 2 is a schematic view showing a backlight module 3 according to an embodiment of the present invention. As shown in Fig. 2, the backlight module 3 includes an optical film assembly 3'' and a light source combination 32' in which the optical film assembly 3' is disposed on the light source assembly 32. The backlight module 3 can be applied to a liquid crystal display. The optical film assembly 3 includes a first diffusion sheet 300, a first wafer 302, a second wafer 3〇4, and a second diffusion sheet 306. The first complex lens 302 is disposed under the first diffusion sheet 3, the second diaphragm 3〇4 is disposed under the first prism sheet 302, and the second diffusion sheet 3〇6 is disposed under the second diaphragm 3〇4. . In other words, the first diffusion sheet 300 is located at the outermost side of the optical film assembly 3〇. 201226994 In this embodiment, the backlight module 3 is a one-side optical backlight module. Therefore, the light source assembly 32 includes a light guide plate 320, a reflection sheet 322, a light source 324, and a reflection plate 326. The light guide plate 320 is disposed under the second diffusion sheet 306 of the optical film assembly 30. The reflection sheet 322 is disposed under the light guide plate 320, the light source 324 is disposed on one side of the light guide plate 320, and the reflection plate 326 is disposed around the light source 324. In practical applications, the light source 324 can be a cold cathode fluorescent lamp (CCFL) or a light emitting diode (LED). It should be noted that the principle of the action of the edge-lit backlight module is well known to those skilled in the art and will not be described herein. 3, FIG. 3, FIG. 3 is a schematic view of the first diffusion sheet 300 in FIG. 2, and FIG. 4 is an exploded view of the first diffusion sheet in FIG. As shown in FIGS. 3 and 4, the first diffusion sheet includes a substrate 3000, a first diffusion layer 3002, and a first
_顆政層3004。基材3000可由任何可使光線透過之 透明材料製成。舉例而言’基材3〇〇〇可為聚乙稀對苯二甲酸酯 ^PET)，但不以此為限。第一擴散層·2設置於基材遞上，且 第二擴散層遍設置於第-擴散層3002上。 第一擴散層3002分人一够. 具有-第-粗細_ 結構81，且第—表面結構81 結構S2以及-第1表面值^CJ。第二擴散層3〇04包含一第二表面 結構S3分別形成於第^其中第—表面結構S2與第三表面 〜擴政層3004之相對二侧。告笛-據私a 3004設置於第-擴散層％ 胃第-擴政層 上寺，第一擴散層3004之第三表面結 201226994 構S3與第-擴散層3002之第-表面結構81重合’換言之，第一 表面結構Si與第三表面結構83為形狀互補，使得第^面結構W 可與第三表面結構S3相互貼合。第二表面結構32具有—第二粗輪 度峰數值Rpc_2。需說明的是，粗經度峰數值（__她㈣ 肌gh_，Rpe)係絲為單位距_的波峰數。由於粗财峰數值 Rpc係為習知技藝之人所熟知，在此不再贅述。 於此貫施例中，第一表面結構 〜一不一必w苑偁以及第三 表面結構S3皆為不規則表面結構，換言之，第—表面結卿、第 構S2以及第三表面結構S3在寬度、高度或結構具細 /刀。此外’第二表面結構幻之第二粗縫度峰數值Rpc」大 於或等於第-表面結構S1之第—_度峰數值如―i (亦即― 咖一2_〇)。由於第三表面結構幻與第—表面結㈣重合， =二面結構S3之織度峰數值係與第-表面結構S〗之粗縫 畜光線: 到Mm 财之表面會進行纖_时散光線，本 更伟酸，11此，#光線通過具有兩層繩度之表面，能夠得麥 等於第- Γ作用°同時’當第二表面結構s2之粗糙度峰數值大於或 值較!:ΐ:ΓSi之粗_值時，光線會先經過婦度峰數 更大之m -表面結MS1進行初步擴散作用，再通過粗糙度峰數值 值表面結構幻，進—步進行擴散作用，以利用粗趟度峰數 触大之第二表⑽構幻加贿讀果。因此，透過上述結構t 201226994 計’當光線通過第-擴散片時，即可得到良好的霧化效果。 此外，當第-擴散片應用於顯示裝置時，第二表面結構幻 會影響品位雜，換言之，第二表面結構S2會料使用者觀看顯干 裝置時的清楚度。當第二表面結構S2之粗糙度峰數值越小，則表面 結構相對越大，而越容易被觀察到表面結構，反之，當第二表砂 構S2之粗糖度峰數值越大，就越不容易被觀察到表面起伏結構^ 此，使用者觀看時，越不容易看到第一擴散片之表面結構秘 力口清楚度，以得到較佳之品位。較佳地，可使每毫米之第一树造产曰 峰數值RPc」以及每毫米之第：粗輪度峰數值咖―2皆大於Η。又 _ 此外，第-表面結構S1可具有—第―^線平均表面粗輪度值 a，且第一表面結構82可具有—第二中心線平均表面粗縫度值 a。本發明可進—步使第二表面結構％之第二中心線平 :=a—:或等於第一表面_ ，度值Ra—i (亦即Ra_gRaJ)。由於第三表面結構幻與第一 值重合’因此第三表面結構S3之中心線平均表面㈣造度 ^第-表面結構81之中心線平均表面嫌度值相同。藉此，當 ^過第-擴散請時，即可得到_霧化效果。較佳地， 财值RaJ可介於㈣微米與_之 米之間第-中心線平均表面粗糙度值Ra—2可介於015微米與職 201226994 需說明的是，巾谢均表_她（_ 3rghneSS，Ra)係定義為在取樣長度内，被測表面之實際輪 郭上各·、』至輪廓中心線距 ” 一係為一所：::值=^^ 且第=卜= 表srsi可具有-苐-最大峰谷高度差值心 可具有—第—最A峰谷高度差值Rz_2。本發明 等於第表面結構S2之第二最场谷高度差值& 2小於或 ::rsi之第一最大峰谷高度差值㈣亦即心 表面社構表面結構幻與第一表面結構81重合，因此第三 古产差°值彳η峰谷减差值_第—表聽構S1之最大峰谷 =值_。獻，枝_财— ==化效果。較佳地，可使第—最大峰谷高度差㈣Γ；；到良 最大峰谷高度差值Μ皆大於0.6微米。 一 需說明的是’最大峰谷高 阳係定義為在崎 谷高度差值Rz係為習知技^人峰谷而度差值。由於最大峰 技w之人所熟知，在此不再贅述。 3004 n2 3000 ，且第一擴散層3002之折射率nl大於 土材3_之折射率的（亦即心 擴散片則，_物喻叫 線通過第一 201226994 需說明的是，雖然上述第一擴散片300係以兩層擴散層來做說 明，但本發明並不以此為限。於本發明之其它實施例中，擴散片亦 可由兩層以上的擴散層堆疊於基材上而組成，其中每一層擴散層之 粗縫度峰數值Rpc與折射率係由上至下遞減，而中心線平均表面粗 糙度值Ra與最大峰谷高度差值!^制上至下遞增。藉此，當光線 通過由兩層以上的擴散層所組成的擴散片時，即可得到良好的霧化 效果。 此外，第2圖中的第二擴散片3〇6之結構可與上述第一擴散片 300之結構相同，以增加光線的霧化效果。 請參閱第5圖’第5圖為根據本發明另一實施例之背光模組 的示意圖。背光模組3’與上述的背光模組3的主要不同 背光模組玲為-直下式背光模組。因此，光源組合32，包含一狀 划以及-反射板329。光源328設置於第二擴散片3〇6下，且反射 板329設置於光源328下。於實際應用中，光源似可為冷陰極管 ^發光二極體。需說_是，直下式縣模組之作闕理為習知技 β之人所熟知’在此科贅述。此外，第5財與第2圖中所 同標號的元件’其作用原理皆相同，在此不再費述。 相較於先前賊，本發明係料_擴散層分卿成 或相同的祕料數值、巾心線平均絲粗财值、最大峰谷高度 201226994 差值及/或折射率之表面結構，以使通過擴散片的光線產生霧化效 果。因此，本發明之擴散片不需於擴散層中摻雜珠粒，進而避免珠 粒脫落或到傷基材表面等問題。 以上所述僅為本發明之較佳實施例，凡依本發明申請專利範圍 所做之均等變化與修飾，皆應屬本發明之涵蓋範圍。 【圖式簡單說明】 第1圖為先前技術之擴散片的示意圖。 第2圖為根據本發明一實施例之背光模組的示意圖。 第3圖為第2圖中的第一擴散片的示意圖。 第4圖為第3圖中的第一擴散片的爆炸圖。 第5圖為根據本發明另一實施例之背光模組的示意圖。 【主要元件符號說明】 3、3， 背光模組 10 擴散片 30 光學膜片組合 32 > 32' 光源組合 100、3000 基材 120 、 140 擴散層 160 珠粒 300 第一擴散片 302 第一稜鏡片 304 第二稜鏡片 306 第二擴散片 320 導光板 322 反射片 324、328 光源 326 > 329 反射板 3002 第一擴散層_ political layer 3004. Substrate 3000 can be made of any transparent material that allows light to pass through. For example, the substrate 3 can be polyethylene terephthalate (PET), but is not limited thereto. The first diffusion layer 2 is disposed on the substrate, and the second diffusion layer is disposed on the first diffusion layer 3002. The first diffusion layer 3002 is divided into one. It has a -th-thickness_structure 81, and the first surface structure 81 structure S2 and the -first surface value ^CJ. The second diffusion layer 3〇04 includes a second surface structure S3 formed on the opposite sides of the first surface structure S2 and the third surface to the diffusion layer 3004, respectively. The whistle-specific private 3004 is set in the first-diffusion layer% stomach-revolutionary layer upper temple, the third surface layer of the first diffusion layer 3004 is 201226994, and the S3 is coincident with the first-surface structure 81 of the first diffusion layer 3002. In other words, the first surface structure Si and the third surface structure 83 are complementary in shape such that the second surface structure W can be bonded to the third surface structure S3. The second surface structure 32 has a second coarse radii peak value Rpc_2. It should be noted that the coarse longitude peak value (__ her (four) muscle gh_, Rpe) is the number of peaks per unit distance _. Since the rough peak value Rpc is well known to those skilled in the art, it will not be repeated here. In this embodiment, the first surface structure - the one surface and the third surface structure S3 are irregular surface structures, in other words, the first surface junction, the first structure S2, and the third surface structure S3 are Width, height or structure with a fine/knife. Further, the second rough surface peak value Rpc of the second surface structure is greater than or equal to the first-degree peak value of the first-surface structure S1 such as "i" (i.e., "cai 2_〇"). Since the third surface structure illusion coincides with the first-surface junction (four), the texture peak value of the two-sided structure S3 and the coarse-grained light of the first-surface structure S: the surface of the Mm financial layer will be ray-scattered , this is more acid, 11 this, #光光的面面的面面, can get the wheat equal to the first - Γ action ° while 'when the second surface structure s2 roughness peak value is greater than or value comparison!: ΐ: When the value of ΓSi is _, the light will first undergo a preliminary diffusion by the m-surface junction MS1 with a larger number of peaks, and then the surface structure of the roughness peak value will be illusory, and the diffusion will be carried out step by step to take advantage of the rough The second table of the number of peaks is large (10). Therefore, when the light passes through the first diffusion sheet through the above structure t 201226994, a good atomization effect can be obtained. Further, when the first diffusion sheet is applied to the display device, the second surface structure illusion affects the grade, and in other words, the second surface structure S2 informs the user of the clarity when the display device is viewed. When the roughness peak value of the second surface structure S2 is smaller, the surface structure is relatively larger, and the surface structure is more easily observed. Conversely, when the value of the coarse sugar peak of the second surface sand structure S2 is larger, the less It is easy to observe the surface relief structure. Therefore, when the user views, it is less easy to see the surface structure of the first diffusion sheet, and the clarity of the surface is obtained to obtain a better taste. Preferably, the first tree yield peak value RPc" per millimeter and the first: coarse wheel peak value per millimeter are greater than Η. Further, the first surface structure S1 may have a -th line average surface roughness value a, and the first surface structure 82 may have a second center line average surface roughness value a. The present invention can further step the second center line of the second surface structure %: = a -: or equal to the first surface _, the degree value Ra - i (i.e., Ra_gRaJ). Since the third surface structure is singularly coincident with the first value, the center line average surface (four) degree of the third surface structure S3 is the same as the center line average surface susceptibility value of the first surface structure 81. In this way, when the first-diffusion is requested, the _ atomization effect can be obtained. Preferably, the financial value RaJ can be between (four) micrometers and _ meters. The first-center line average surface roughness value Ra-2 can be between 015 micrometers and the job 201226994. It should be noted that the towel Xie Jun table _ her (_ 3rghneSS , Ra) is defined as the length of the actual surface of the surface to be measured, and the line-to-center distance of the contour of the measured surface is one in a series::: value = ^^ and the first = b = table srsi can have - The 苐-maximum peak-to-valley height difference heart may have a -first-most A-valley height difference Rz_2. The present invention is equal to the second-most valley-height difference of the first surface structure S2 & 2 is less than or:: rsi first The difference between the maximum peak-to-valley height (4), that is, the surface structure of the heart surface is coincident with the first surface structure 81, so the third paleo-product difference value 彳η peak- valley reduction difference_the first peak of the listening structure S1 = value _. contribution, branch _ _ - = = effect. Preferably, the first - maximum peak-to-valley height difference (four) Γ;; to the best peak-to-valley height difference Μ are greater than 0.6 microns. 'Maximum peaks and valleys are defined as the difference between the Rz system and the peaks and valleys in the Sakiguchi height. Because of the maximum peak skill, people are well known. 3004 n2 3000, and the refractive index nl of the first diffusion layer 3002 is greater than the refractive index of the soil material 3_ (that is, the core diffusion sheet, the _ metaphor called the line through the first 201226994 Although the first diffusion sheet 300 is described by two diffusion layers, the present invention is not limited thereto. In other embodiments of the present invention, the diffusion sheet may be stacked on the base by two or more diffusion layers. The composition is composed of materials, wherein the coarseness peak value Rpc and the refractive index of each diffusion layer are decreased from top to bottom, and the average line surface roughness value Ra and the maximum peak-to-valley height difference of the center line are increased from top to bottom. Thereby, when the light passes through the diffusion sheet composed of the diffusion layer of two or more layers, a good atomization effect can be obtained. Further, the structure of the second diffusion sheet 3〇6 in FIG. 2 can be compared with the above A diffusion sheet 300 has the same structure to increase the atomization effect of the light. Please refer to FIG. 5, which is a schematic diagram of a backlight module according to another embodiment of the present invention. The backlight module 3' and the backlight module described above are used. Group 3's main different backlight modules are Ling-straight back Therefore, the light source assembly 32 includes a shape and a reflection plate 329. The light source 328 is disposed under the second diffusion sheet 3〇6, and the reflection plate 329 is disposed under the light source 328. In practical applications, the light source may be It is a cold cathode tube ^ light-emitting diode. It should be said that _ is, the direct-down county module is well-known for people familiar with the technology of the 'technical' in this section. In addition, the fifth and second pictures The components of the same reference numerals have the same principle of operation, and will not be described here. Compared with the previous thief, the present invention is a material-diffusion layer that is divided into the same secret value or the average value of the core of the towel. Maximum peak-to-valley height 201226994 The surface structure of the difference and/or refractive index to produce a fogging effect on the light passing through the diffuser. Therefore, the diffusion sheet of the present invention does not need to be doped with beads in the diffusion layer, thereby avoiding problems such as falling off of the beads or damage to the surface of the substrate. The above are only the preferred embodiments of the present invention, and all changes and modifications made to the scope of the present invention should fall within the scope of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a schematic view of a diffusion sheet of the prior art. FIG. 2 is a schematic diagram of a backlight module according to an embodiment of the invention. Fig. 3 is a schematic view of the first diffusion sheet in Fig. 2. Fig. 4 is an exploded view of the first diffusion sheet in Fig. 3. FIG. 5 is a schematic diagram of a backlight module according to another embodiment of the present invention. [Main component symbol description] 3, 3, backlight module 10 diffuser 30 optical film combination 32 > 32' light source combination 100, 3000 substrate 120, 140 diffusion layer 160 bead 300 first diffusion sheet 302 first edge Lens 304 second diaphragm 306 second diffusion sheet 320 light guide plate 322 reflection sheet 324, 328 light source 326 > 329 reflection plate 3002 first diffusion layer
S 12 201226994 3004 第二擴散層 S1 S2 第二表面結構S3 第一表面結構 第三表面結構S 12 201226994 3004 second diffusion layer S1 S2 second surface structure S3 first surface structure third surface structure
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