201007294 - 九、發明說明： 【發明所屬之技術領域】 本發明涉及一種直下式背光模組，尤其涉及一種應用 於液晶顯示之直下式背光模組。 【先前技術】 液晶顯不裝置被廣泛應用於個人數位助理、筆記型電 腦、數位相機、移動電話、液晶電視等電子產品中。但由 於液晶顯示裝置本身不能發光，因此其需要借助背光模組 ©才能產生顯示功能。 請參見圖1’ 一種直下式背光模組1〇〇包括框架1〇， 一反射板12、複數發光二極體14、一擴散板16及複數光 學片18。複數發光二極體14設置在框架10之底板上，複 數光學片18蓋設於框架10開口處。擴散板16間隔設置於 發光二極體14及複數光學片18之間，從而將框架内分 割成第一和第二擴散空間15、17。擴散板16由含有散射粒 子之樹脂材料製成。該複數光學片18包括稜鏡片、擴散片 或折射偏振膜。 使用時，由複數發光二極體14產生之光線經第一擴散 空間15後進入擴散板16，經擴散板16擴散後，光線進入 第二擴散空間17進行擴散，最後經過複數光學片18之擴 散或聚集作用後，在特定視角範圍内均勻出射。 從發光二極體14發出之光線雖經多次擴散，但仍报難 避免發光二極體14光源殘影之產生。為了儘量減少光源殘 影之產生，業界通常會增大框架1〇之深度，即增大第—和 6 201007294 ,丨、屮M=工間15、17之尚度 '然* ’增加框架之深度將減 先之亮度。假如相應增加發光二極體14之數量，會 成本及使用時之消耗功率。而增大框架10之深度 .將使旁光模組難以滿足薄型化設計之要求。 【發明内容】 且严^於Ϊ述狀況，有必要提供—種出射光線均勻性較佳 且厚度較薄之直下式背光模組。 ❹坪直下光模組，其包括—框架、複數發光二極 體、-擴散板、-第一光學板和一第二光學板。複數發光 -極體設置於該框架底板上，擴散板設置於發光二極體上 方，第二光學板設置於擴散板與發光二極體之間，第 學板設置於擴散板上方。第一光學板包括一入光面及盘該 入光面相對之出光面，第一光學板之出光面形成有複數光 學微結構。第二光學板包括一入光面及與該入光面相對之 出光面，該第二光學板之出光面為平面，該第二光學板之 ❹入光面靠近發光二極體。第二光學板還包括形成於入光面 之沿至少二不同方向延伸之複數ν形脊結構，該沿不同方 向延伸之V形脊結構相互交錯。 上述直下式背光模組，藉由在靠近發光二極體上方位 置設置一入光面具有相互交錯之V形脊結構之第二光學板 以及一擴散板，使得發光二極體出射光線經第二光學2反 射和折射以及擴散板擴散後，向發光二極體二側擴2,可 使出射光線之照射區域向四週拓展形成具有較大面積之面 光源。另’藉由形成於第-光學板出光面之光學微結構進 201007294 行集光，可提高出射光線之正面亮度。從而，即使採用較 少數量之發光二極體或較淺深度之框架仍可形成均勻性較 ，佳之面光源，滿足較低成本和薄型化設計要求。 【實施方式】 下面將結合附圖及具體實施例對本發明直下式背光模 組作進一步詳細說明。 請參見圖2,本發明實施例一直下式背光模組200包括 一框架21、設置於框架21底板上之複數發光二極體22、 ❹一擴散板24、一第一光學板25以及一第二光學板23。第 一光學板25設於框架21之開口端。擴散板24設於發光二 極體22上方。第二光學板23設於發光二極體22和擴散板 24之間。第一光學板25和擴散板24間隔一定距離，從而 形成一擴散空間26。 框架21可由表面具有高反射率之金屬或塑膠製成，亦 可於框架21内壁塗佈具有高反射率之塗層，以使光線在框 ©架21内能夠完全反射。框架21具有用於承載和支撐發光 二極體22、擴散板24、第一光學板25以及第二光學板2 之支撐結構。 請參見圖3，第二光學板23由透明材料製成，透明本 體包括入光面231及與入光面231相對之出光面232，其 中，出光面232為平面。第二光學板23在入光面231形成 有複數沿第一方向X:延伸之V形脊結構234a、複數沿第二 方向X2延伸之V形脊結構234b、複數沿第三方向X3延伸 之V形脊結構234c及複數沿第四方向X4延伸之V形脊結 201007294 •構234d。上述複數v形脊結構相互交錯。四個方向χ X2、X3*X4中’相鄰二方向間之夾角為45度，該w眷 ，結構之頂角可為80度至⑽度，同方向上相鄰 二 ‘之間之中心距離可為咖毫米至i毫米。四個方向/ x2、m4相鄰v形凸起間之中心距離分別 、1 與d4’ d1=d3=如2=如4。沿四個方向Hu 3 延伸之複數v形脊結構相互交錯形成具有複數相互連接之4 具有共同連接點之三稜錐凹槽说，具有共同連接 ❹，凹槽234相互連接之侧壁形成四角星形说，且複數:J 星形236呈矩形陣列排饰。 第二光學板23厚度τ可為〇.4毫米至4絲。第 學板23可由聚甲基丙烯酸甲g|、聚碳酸酯、聚笨乙歸 乙埽-甲基丙騎甲S旨共聚物中之―種或―種以上之材料主 塑成型而成。製備過程中需在模具上設置與四稜錐凹槽2;4201007294 - IX. Description of the Invention: [Technical Field] The present invention relates to a direct type backlight module, and more particularly to a direct type backlight module applied to a liquid crystal display. [Prior Art] Liquid crystal display devices are widely used in electronic products such as personal digital assistants, notebook computers, digital cameras, mobile phones, and LCD TVs. However, since the liquid crystal display device itself cannot emit light, it is necessary to use the backlight module © to generate a display function. Referring to Fig. 1', a direct type backlight module 1A includes a frame 1 〇, a reflecting plate 12, a plurality of light emitting diodes 14, a diffusing plate 16, and a plurality of optical sheets 18. The plurality of light-emitting diodes 14 are disposed on the bottom plate of the frame 10, and the plurality of optical sheets 18 are disposed at the openings of the frame 10. The diffusion plate 16 is spaced apart between the light-emitting diodes 14 and the plurality of optical sheets 18 to divide the inside of the frame into the first and second diffusion spaces 15, 17. The diffusion plate 16 is made of a resin material containing scattering particles. The plurality of optical sheets 18 include a gusset, a diffusion sheet or a refractive polarizing film. In use, the light generated by the plurality of light-emitting diodes 14 passes through the first diffusion space 15 and enters the diffusion plate 16. After being diffused by the diffusion plate 16, the light enters the second diffusion space 17 for diffusion, and finally passes through the diffusion of the plurality of optical sheets 18. Or after aggregating, it is uniformly emitted within a specific viewing angle range. Although the light emitted from the light-emitting diode 14 is diffused many times, it is still difficult to avoid the generation of the residual light of the light-emitting diode 14 light source. In order to minimize the generation of residual light source, the industry will generally increase the depth of the frame, that is, increase the number of - and 6 201007294, 丨, 屮 M = the degree of the work room 15, 17 '*' increase the depth of the frame Will reduce the brightness first. If the number of light-emitting diodes 14 is increased correspondingly, the cost and power consumption during use will be incurred. Increasing the depth of the frame 10 will make it difficult for the backlight module to meet the requirements of a thin design. SUMMARY OF THE INVENTION It is necessary to provide a direct-lit backlight module in which the uniformity of the emitted light is uniform and the thickness is thin. The ❹ flat straight light module comprises a frame, a plurality of light emitting diodes, a diffusing plate, a first optical plate and a second optical plate. The plurality of illuminating electrodes are disposed on the bottom plate of the frame, the diffusing plate is disposed above the light emitting diode, and the second optical plate is disposed between the diffusing plate and the light emitting diode, and the first plate is disposed above the diffusing plate. The first optical plate comprises a light-incident surface and a light-emitting surface of the disk opposite to the light-incident surface, and the light-emitting surface of the first optical plate is formed with a plurality of optical microstructures. The second optical plate includes a light incident surface and a light emitting surface opposite to the light incident surface. The light emitting surface of the second optical plate is a flat surface, and the light incident surface of the second optical plate is close to the light emitting diode. The second optical plate further includes a plurality of ν-shaped ridge structures formed in at least two different directions formed on the light incident surface, the V-shaped ridge structures extending in different directions being staggered with each other. In the above-mentioned direct type backlight module, a second optical plate having a V-shaped ridge structure interlaced with each other and a diffusion plate are disposed at a position above the light-emitting diode, so that the light-emitting diode emits light through the second After the reflection and refraction of the optical 2 and the diffusion of the diffusion plate, the two sides of the light-emitting diode are expanded by two, and the irradiation region of the emitted light can be expanded to form a surface light source having a large area. In addition, the front surface brightness of the emitted light can be increased by collecting light from the optical microstructure formed on the light-emitting surface of the first optical plate into the 201007294 line. Therefore, even a relatively small number of light-emitting diodes or a shallow depth frame can form a uniform surface light source, which satisfies lower cost and thin design requirements. [Embodiment] Hereinafter, the direct type backlight module of the present invention will be further described in detail with reference to the accompanying drawings and specific embodiments. Referring to FIG. 2 , the backlight module 200 of the present invention comprises a frame 21 , a plurality of LEDs 22 disposed on the bottom plate of the frame 21 , a diffusion plate 24 , a first optical plate 25 , and a first Two optical plates 23. The first optical plate 25 is provided at the open end of the frame 21. The diffusion plate 24 is disposed above the light emitting diode 22. The second optical plate 23 is disposed between the light emitting diode 22 and the diffusion plate 24. The first optical plate 25 and the diffusion plate 24 are spaced apart to form a diffusion space 26. The frame 21 can be made of metal or plastic having a high reflectivity on the surface, and a coating having a high reflectance can be applied to the inner wall of the frame 21 so that the light can be completely reflected in the frame. The frame 21 has a support structure for supporting and supporting the light-emitting diode 22, the diffusion plate 24, the first optical plate 25, and the second optical plate 2. Referring to FIG. 3, the second optical plate 23 is made of a transparent material. The transparent body includes a light incident surface 231 and a light exit surface 232 opposite to the light incident surface 231. The light exit surface 232 is a flat surface. The second optical plate 23 is formed on the light incident surface 231 with a plurality of V-shaped ridge structures 234a extending in the first direction X: a plurality of V-shaped ridge structures 234b extending in the second direction X2, and a plurality of V extending in the third direction X3. The ridge structure 234c and the plurality of V-shaped ridges 201007294 extending in the fourth direction X4 are configured as 234d. The plurality of v-shaped ridge structures are interlaced with each other. In the four directions χ X2, X3*X4, the angle between the adjacent two directions is 45 degrees, the w 眷, the apex angle of the structure may be 80 degrees to (10) degrees, and the center distance between adjacent two 's in the same direction may be For coffee mm to i mm. The center distance between the adjacent v-shaped projections in four directions / x2, m4, respectively, 1 and d4' d1 = d3 = as 2 = as 4. The plurality of v-shaped ridge structures extending in four directions Hu 3 are interlaced to form a plurality of mutually connected 4 triangular pyramid grooves having a common connection point, and have a common connection, and the side walls of the grooves 234 are connected to each other to form a four-pointed star. Shape, and plural: J star 236 is a rectangular array of ornaments. The thickness τ of the second optical plate 23 may be 〇.4 mm to 4 wires. The second board 23 may be formed by molding a material of the polymethyl methacrylate, the polycarbonate, the polystyrene, the acetoxime-methyl propyl group, or the above-mentioned materials. During the preparation process, it is necessary to set the square pyramid groove 2 on the mold; 4
:應之凸起結構，以便使第二光學板23可在單次注塑過程 中成型。 請再次參見圖2,擴散板24為—平板，其由分散有散 ^子旭=明材料組成，散射粒子242可為二氧化欽 粒、一虱化矽微粒和丙烯酸樹脂微粒中之一種或一種以 上之混合物。可以理解，藉由調整散射粒子242與構 散板24透明本體材料之比例可以調節擴散板μ之 率，將擴散板26之透光率控制在8()%以上為較佳選擇。 請參見圖4 ’第—光學板25由透明材料製成，包括一 入光面25i和與入光面251相對之出光面况。其中，入光 201007294: The raised structure should be such that the second optical plate 23 can be formed in a single injection molding process. Referring again to FIG. 2, the diffusion plate 24 is a flat plate composed of a dispersed dispersion material, and the scattering particles 242 may be one or a combination of a oxidized granule, a bismuth bismuth hydride particle, and an acrylic resin particle. The above mixture. It can be understood that the ratio of the diffusing plate μ can be adjusted by adjusting the ratio of the scattering particles 242 to the transparent body material of the dispersing plate 24, and it is preferable to control the light transmittance of the diffusing plate 26 to 8 ()% or more. Referring to Fig. 4, the first optical plate 25 is made of a transparent material, and includes a light incident surface 25i and a light exiting surface opposite to the light incident surface 251. Among them, entering the light 201007294
面251為平面。第一 ^ I 學微钍構m ^千板之出光面252形成有複數光 感。構，该複數光學微結構由沿第 元 •脊結構254a、複數沿第二方向χ延# 1 形 複數产Μ - f Α γ 2乙伸之V形脊結構254b、 之¥形脊結構W數沿第四 向X4延狀V形脊結構254d交錯形成。 延伸之V形脊結構254b與沿第 〇 一向X2 ^ t, 2 、D弟四方向X4延伸之V形脊牡 自杨延伸之v形脊結構加與^ ❹X二χ Γ:Γ形脊結構咖間之交點。四個方向 “構2之f3备：相鄰一方向間之夾角為45度，該¥形 =構之頂角可為80度至1〇〇度，同方向上相 ： Γχ之中心距離可為〇·025毫米至1毫米。四個方向J t、X3及x4相鄰V形脊結構間之中心距離分別為Di、D2、 、D4 ’ Dl=D3為2為4。上述v形脊結構相互交錯形 、具有複數相互連接之具有共同連接點之三稜錐凹槽 Γ’,具有共同連接點之三稜錐凹槽255相互連接之側“ φ成四角星形256,且複數四角星形攻呈矩形陣列排佈。 為進-步提南出射面光源之均句性，還可以在第 學板25上方還設置光學片3〇。光學片3〇可以為光擴散片、 增光片或者反射式偏光片。 、 在直下式背光模、组200中，第二光學板23之入光面231 與該複數發光二極體22頂部相靠近，二者間距離小於或等 於3毫米。擴散板24與第一光學板25於垂直方向具有一 預設高度，其高度範圍大於或等於1〇毫米。在本實施例中， 擴散板24出光面與第一光學板25之入光面251間之垂直 201007294 ' 距離為ίο毫米。當然，二者間之距離可以實際情況作調整， 一般地，在出光均勻度相同之情況下，框架21之深度與發 . 光二極體22之數量成反平方比。當發光二極體22數量較 _ 多時，框架21之深度較小，第一光學板25與擴散板24間 隔距離可設置得小一些。當發光二極體22數量較少時，框 架21之深度較大，第一光學板25與擴散板24間隔距離相 應地設置得大一些。 使用時，發光二極體22出射之光線直接或經框架21 ®内壁反射、擴散後進入第二光學板23。其中，大致朝向發 光二極體22正上方出射之光線在第二光學板23入光面231 處首先發生全反射，之後再經框架21内壁反射進入第二光 學板23。由於第二光學板23材質之折射率不同於空氣之折 射率，入射至第二光學板23之光線在入光面231和出光面 232處發生折射後向發光二極體22兩側出射。藉由擴散板 24擴散作用後，光線進入擴散空間26及進行進一步擴散， I從而，發光二極體22照射區域向四週拓展形成具有較大面 馨 積之面光源，此外，發光二極體22上方出現之亮點亦得到 改善。之後，光線進入第一光學板25進行勻光和聚集，第 一光學板25出光面252之光學微結構可提升光線之正面亮 度並形成均勻之面光源。 請參見圖5，本發明實施例二第二光學板43與實施例 一第二光學板23相似，其不同之處在於：第二光學板43 具有形成於入光面431之複數沿第一方向Χχ延伸之V形脊 結構433a、複數沿第二方向X2延伸之V形脊結構433b以 11 201007294 及複數沿第三方6 v ... 向&延伸之v形脊結構433c。上诚v 脊結構相互交錯。 上这V形 通過沿第-方向γ 3延伸之V形脊結構433c • 向Xl延伸之V形脊結構433a與沿第-太& X2延伸之V形眷蛀姐， 、口弟一方向 * 含、、、。構433b間之交點。第一方向 方向X』之夹角為90度，第三方向Χ3與第一、第 之夾角分別為45度和135度。上述ν形脊結二 互父錯形成相互遠技—矣 籌相 互連接之二稜錐形凹槽435與四稜錐形凹槽 ，/、中母一四稜錐凹槽436由相鄰之四個三稜 ^ 霽435所包圍。 仪哗W槽 一圖6至圖8所示為本發明實施例三第一光學板牦。第 一光學板45包括由透明材料製成，其包括人光面451及與 入光面451相對之出光面452。出光面452具有複數交替排 佈且相互平行之長條狀v型凸起456及長條狀弧形凸起 458入光面451具有複數相互平行之長條狀弧形凹槽 459。戎複數長條狀ν型凸起456或長條狀弧形凸起々π之 ❹延伸方向與複數長條狀弧形凹槽459之延伸方向相交。本 實施例中，該複數長條狀v型凸起456或長條狀弧形凸起 258之延伸方向與複數長條狀弧形凹槽459之延伸方向相 互垂直。該長條狀弧形凸起458之垂直截面為半圓弧形， 該長條狀弧形凹槽459之垂直截面為半圓弧形。可以理解， 長條狀孤形凸起458與長條狀弧形凹槽459之垂直載面還 可為橢圓弧形。Face 251 is a flat surface. The light surface 252 of the first ^I micro-structure is formed with a plurality of light perceptions. The complex optical microstructure consists of a V-shaped ridge structure 254b along the ridge structure 254a, a plurality of ridges 254b in the second direction, and a ridge structure 254b. The fourth X4 extended V-shaped ridge structure 254d is alternately formed. The extended V-shaped ridge structure 254b and the V-shaped ridge structure extending from the southward direction of the V-shaped ridges extending along the X-axis X2^t, 2, D, and the fourth direction X4 are added to the 形X χ Γ: Γ-shaped ridge structure The intersection of coffee and coffee. In the four directions, the f3 of the structure 2: the angle between the adjacent directions is 45 degrees, and the apex angle of the structure can be 80 degrees to 1 degree, and the phase in the same direction: the center distance of the Γχ can be 〇 025 mm to 1 mm. The center distance between adjacent V-shaped ridge structures in the four directions J t, X3 and x4 is Di, D2, D4 'Dl=D3 is 2 is 4. The above v-shaped ridge structures are interlaced a triangular pyramid groove Γ' having a plurality of interconnecting points having a common connection point, a side of the triangular pyramid groove 255 having a common connection point connected to each other "φ is a four-pointed star 256, and a plurality of four-corner stars are attacked A rectangular array is arranged. In order to advance the step-by-step appearance of the surface light source, an optical sheet 3 还 can also be disposed above the first board 25. The optical sheet 3 can be a light diffusion sheet, a brightness enhancement sheet or a reflective polarizer. In the direct type backlight module, the group 200, the light incident surface 231 of the second optical plate 23 is close to the top of the plurality of light emitting diodes 22, and the distance therebetween is less than or equal to 3 mm. The diffusion plate 24 and the first optical plate 25 have a predetermined height in the vertical direction and a height range of greater than or equal to 1 mm. In the present embodiment, the vertical distance between the light-emitting surface of the diffusing plate 24 and the light-incident surface 251 of the first optical plate 25 is ίο mm. Of course, the distance between the two can be adjusted in practice. Generally, the depth of the frame 21 is inversely proportional to the number of the light-emitting diodes 22 in the case where the uniformity of light emission is the same. When the number of the light-emitting diodes 22 is more than _, the depth of the frame 21 is small, and the distance between the first optical plate 25 and the diffusion plate 24 can be set smaller. When the number of the light-emitting diodes 22 is small, the depth of the frame 21 is large, and the distance between the first optical plate 25 and the diffusion plate 24 is correspondingly set larger. In use, the light emitted from the LED 22 is reflected or diffused directly through the inner wall of the frame 21 ® and enters the second optical plate 23 . The light emitted substantially directly toward the light-emitting diode 22 is first totally reflected at the light-incident surface 231 of the second optical plate 23, and then reflected into the second optical plate 23 via the inner wall of the frame 21. Since the refractive index of the material of the second optical plate 23 is different from the refractive index of the air, the light incident on the second optical plate 23 is refracted at the light incident surface 231 and the light exit surface 232, and then emitted toward both sides of the light emitting diode 22. After the diffusion plate 24 diffuses, the light enters the diffusion space 26 and further diffuses, so that the illumination region of the light-emitting diode 22 expands to the periphery to form a surface light source having a large surface area. Further, the light-emitting diode 22 The highlights appearing above have also been improved. Thereafter, the light enters the first optical plate 25 for homogenization and focusing, and the optical microstructure of the light exiting surface 252 of the first optical plate 25 enhances the front luminance of the light and forms a uniform surface light source. Referring to FIG. 5, the second optical plate 43 of the second embodiment of the present invention is similar to the second optical plate 23 of the first embodiment, except that the second optical plate 43 has a plurality of first light directions formed on the light incident surface 431. The extended V-shaped ridge structure 433a, the plurality of V-shaped ridge structures 433b extending in the second direction X2 are 11 201007294 and a plurality of V-shaped ridge structures 433c extending along the third direction. The Shangcheng v ridge structure is intertwined. The V-shape passes through the V-shaped ridge structure 433c extending in the first direction γ 3 • the V-shaped ridge structure 433a extending toward X1 and the V-shaped scorpion extending along the first-to-the-X2, and the direction of the younger brother* Contains,,,. The intersection between 433b. The angle between the first direction and the direction X′′ is 90 degrees, and the angle between the third direction Χ3 and the first and the first is 45 degrees and 135 degrees, respectively. The above-mentioned v-shaped ridges and two mutual fathers form a mutual telescope--the two-sided pyramidal groove 435 and the quadrangular pyramidal groove which are interconnected, and the middle mother-four-sided pyramid groove 436 is adjacent to the fourth Surrounded by three triangles 霁 435.哗 哗 W slot A FIG. 6 to FIG. 8 show a first optical plate 实施 according to a third embodiment of the present invention. The first optical plate 45 is made of a transparent material and includes a human light surface 451 and a light exit surface 452 opposite to the light incident surface 451. The light-emitting surface 452 has a plurality of strip-shaped v-shaped projections 456 and a strip-shaped curved projection 458 which are alternately arranged and parallel to each other, and the light-incident surface 451 has a plurality of elongated arcuate grooves 459 which are parallel to each other. The extension direction of the plurality of elongated v-shaped projections 456 or the elongated arcuate projections π intersects the extending direction of the plurality of elongated arcuate grooves 459. In this embodiment, the extending direction of the plurality of elongated v-shaped projections 456 or the elongated arcuate projections 258 is perpendicular to the extending direction of the plurality of elongated arcuate grooves 459. The vertical section of the elongated arcuate projection 458 has a semicircular arc shape, and the vertical section of the elongated arcuate groove 459 has a semicircular arc shape. It can be understood that the vertical load faces of the elongated elongated protrusions 458 and the elongated curved grooves 459 can also be elliptical curved.
將長條狀V型凸起456之寬度記為D，頂角記為θ，高 度记為Η!;則D、θ、Η!滿足如下關係式：〇.〇25毫米^ D 12 201007294 毫米’80度Μ錢〇度，㈣毫米將 長條狀弧形凸起458之寬度記為L，半徑記為r，高产 H2,則L、R、H2滿足如下關係式：〇〇25亳米 米，L/d^2L，0.〇mH<R。藉由調節 D、=e、·^ L、R、及H2之數值，可調整長條狀V型凸起456及長條 狀弧形凸起45 8之形狀，從而調節第—光學板4 $之妗 及出光視角。 θ 相鄰二長條狀弧形凹槽459之間距記為ρ，半徑計為 r’南度記為h，則P、r&h滿足如下關係式：〇〇25毫米The width of the long V-shaped projection 456 is denoted by D, the apex angle is denoted by θ, and the height is denoted by Η!; then D, θ, Η! satisfies the following relationship: 〇.〇25 mm^D 12 201007294 mm' 80 degrees of money, (4) mm, the width of the long arc-shaped protrusion 458 is recorded as L, the radius is recorded as r, and the high-yield H2, then L, R, H2 satisfy the following relationship: 〇〇 25 亳 m, L/d^2L, 0. 〇mH < R. By adjusting the values of D, =e, ·^ L, R, and H2, the shape of the elongated V-shaped projection 456 and the elongated arc-shaped projection 45 8 can be adjusted, thereby adjusting the first optical plate 4 $ After the light and the viewing angle. θ The distance between adjacent two long strip-shaped curved grooves 459 is denoted by ρ, and the radius is calculated as r'. The south degree is recorded as h, then P, r & h satisfy the following relationship: 〇〇 25 mm
SpU.5毫米，ρ/4^2ρ’㈣丄毫米以^。藉由調節p、SpU. 5 mm, ρ/4^2ρ' (four) 丄 mm to ^. By adjusting p,
Qh之數值，可調整長條狀弧形凹槽物之表面曲率及間 距，從而調節對複數長條狀弧形凹槽459對入射光之擴 效果。 、 —第-光學板45可由聚甲基丙稀酸甲醋、聚碳酸醋、聚 本乙烯、苯乙烯-甲基丙烯酸甲酯共聚物中一種或一種以上 瘳材料注塑成型而成。製備過程中需在模具上設置與長條狀v 型凸起456和長條狀弧形凸起458相應之凹陷結構，以及 與長條狀弧形凹槽459相應之凸出結構，以便使第一光學 板45在單次注塑過程中成型。 第一光學板45採用注塑成型方式一體成型，其上之長 條狀V型凸起456及長條狀弧形凸起458和第一光學板衫 其他部分-起形成，因此可使得長條狀v型凸起456及長 :狀弧形㈣458具有較高之結構強度，同時還能提升長 ”狀V型凸起456及長條狀弧形凸起458和第一光學板衫 13 201007294 其他部分之結合力，從而可避免或減少長條狀v型凸起456 及長條狀弧形凸起458在使用中被損壞之危險。第—光學 f 45具有將點光源直接轉換為均勻分佈之面光源之優點。 第一光學板45出光面452之長條狀v型凸起456可以省 略’而僅設置複數相互平行之長條狀弧形凸起倒，長條狀 弧形凸起458之延伸方向與入光面451之複數長條狀弧形 凹槽459之延伸方向相互垂直。 ❹可以理解’第二光學板23還可料人光面形成複數沿 第一方向延伸之v形脊結構、複數沿第二方向延伸之ve 脊結構。沿第-方向和第二方向延伸之¥形脊結構垂直相 交，從而形成複數四稜錐凹槽，相鄰四稜錐凹槽之 相連並呈矩形陣列排佈。 '' 第一光學板25還可於其出光面形成複數沿第一方向延 :之V，脊結構、複數沿第二方向延伸之v形脊結構以及 =數沿第三方向延伸之V形脊結構，上述V形脊結構相互 ❹父錯形成具有集光作用之光學微結構。沿其中一方向延伸 =復數V形脊結構通過沿另外二不同方向延伸之復數V形 脊結構間之交點。。 / 第一光學板25還可於其出光面形成複數沿第—方向 申之v形脊結構、複數沿第二方向延伸之v形脊纟士構， j述二方向延伸之V形脊結構相互垂直相交形成具有集 作用之光學微結構。 ’、 0 综上所述，本發明確已符合發明專利之要件，遂依 提出專利申請。惟，以上所述者僅為本發明之較佳實施 201007294 式，自不能以此限制本案之申請專利範圍。舉凡熟悉本案 技藝之人士援依本發明之精神所作之等效修飾或變化，皆 .應涵蓋於以下申請專利範圍内。 . 【圖式簡單說明】 圖1係一種直下式背光模組之剖面示意圖。 圖2係本發明直下式背光模組實施例一之剖面示意圖。 圖3係圖2直下式背光模組之第二光學板之立體圖。 圖4係圖2直下式背光模組之第一光學板之立體圖。 圖5係本發明實施例二之第二光學板之立體圖。 圖6係本發明實施例三之第一光學板之立體圖。 圖7係圖6所示第一光學板VII-VII方向之剖視圖。 圖8係圖6所示第一光學板yin-VIII方向之剖視圖。 【主要元件符號說明】 直下式背光模組 100、200 框架 10、21 反射板 12 發光二極體 14 > 22 擴散板 16 ' 24 光學片 18 ' 30 第一擴散空間 15 第二擴散空間 17 第二光學板 23、43 入光面 231 、 251 、 431 、 451 出光面 232 、 252 、 432 、 452 15 201007294 三稜錐凹槽 234、255、435 四角星形 236 、 256 第一 V型脊結構 234a、254a ' 433a 第二V型脊結構 234b > 254b ' 433b 第三V型脊結構 234c、254c、433c 第四V型脊結構 234d 、 254d 散射粒子 242 第一光學板 25、45 擴散空間 26 光學片 30 四棱錐凹槽 436 V形凸起 456 弧形凸起 458 弧形凹槽 459 參 16The value of Qh can adjust the surface curvature and the spacing of the long arc-shaped grooves to adjust the effect of the expansion of the complex strip-shaped curved grooves 459 on the incident light. The first optical plate 45 may be injection molded from one or more kinds of bismuth materials of polymethyl methacrylate, polycarbonate, polycarbonate, and styrene-methyl methacrylate copolymer. During the preparation process, a concave structure corresponding to the long v-shaped protrusions 456 and the elongated arc-shaped protrusions 458 and a protruding structure corresponding to the long-shaped curved grooves 459 are provided on the mold, so that the first An optical plate 45 is formed during a single injection molding process. The first optical plate 45 is integrally formed by injection molding, and the long V-shaped protrusions 456 and the elongated arc-shaped protrusions 458 thereon and the other portions of the first optical plate are formed, thereby making the strips The v-shaped projection 456 and the long: arc-shaped (four) 458 have a higher structural strength, and at the same time, the long-shaped V-shaped projection 456 and the elongated arc-shaped projection 458 and the first optical plate-shaped shirt 13 201007294 can be lifted. The bonding force can avoid or reduce the risk of the long v-shaped protrusions 456 and the elongated arc-shaped protrusions 458 being damaged in use. The first optical f 45 has the function of directly converting the point source into a uniform distribution. The advantage of the light source. The long v-shaped protrusion 456 of the light-emitting surface 452 of the first optical plate 45 can be omitted, and only a plurality of long-shaped arc-shaped protrusions parallel to each other are arranged, and the extension of the elongated arc-shaped protrusion 458 The direction of the plurality of elongated arcuate grooves 459 of the light incident surface 451 is perpendicular to each other. ❹ It can be understood that the second optical plate 23 can also form a plurality of v-shaped ridge structures extending in the first direction. a plurality of ve ridge structures extending in the second direction. along the first direction and the second The extended ridge structures are perpendicularly intersected to form a plurality of quadrangular pyramid grooves, and adjacent quadrangular pyramid grooves are connected and arranged in a rectangular array. '' The first optical plate 25 can also be formed on the light exit surface thereof. a plurality of V-shaped ridge structures extending in a first direction, a ridge structure, a plurality of v-shaped ridge structures extending in a second direction, and a V-shaped ridge structure extending in a third direction, wherein the V-shaped ridge structures are formed by mutual dislocation Optical microstructure of light action. Extending in one direction = complex V-shaped ridge structure by the intersection of a plurality of V-shaped ridge structures extending in two other different directions. / First optical plate 25 can also form a plurality of radiant surfaces A v-shaped ridge structure extending along the first direction, a plurality of v-shaped ridges extending in the second direction, and a V-shaped ridge structure extending in two directions perpendicularly intersect each other to form an optical microstructure having a collecting action. In summary, the present invention has indeed met the requirements of the invention patent, and the patent application is filed. However, the above description is only the preferred embodiment of the present invention 201007294, which cannot limit the scope of the patent application of the present invention. Familiar with the case The equivalent modifications or variations made by the skilled person in accordance with the spirit of the present invention are intended to be included in the scope of the following patent application. [Simplified Schematic] FIG. 1 is a schematic cross-sectional view of a direct type backlight module. FIG. 3 is a perspective view of the second optical plate of the direct type backlight module of FIG. 2. FIG. 4 is a perspective view of the first optical plate of the direct type backlight module of FIG. Figure 5 is a perspective view of a second optical plate according to a second embodiment of the present invention. Figure 6 is a perspective view of a first optical plate according to a third embodiment of the present invention. Figure 7 is a cross-sectional view of the first optical plate VII-VII shown in Figure 6. Figure 8 is a cross-sectional view of the first optical plate yin-VIII direction shown in Figure 6. [Description of main component symbols] Direct type backlight module 100, 200 Frame 10, 21 Reflector 12 Light-emitting diode 14 > 22 Diffuser 16 ' 24 Optical sheet 18 ' 30 First diffusion space 15 Second diffusion space 17 Two optical plates 23, 43 light-incident surface 231, 251, 431, 451 light-emitting surface 232, 252, 432, 452 15 201007294 triangular pyramid groove 234, 255, 435 square star 236, 256 first V-shaped ridge structure 234a 254a ' 433a second V-shaped ridge structure 234b > 254b ' 433b third V-shaped ridge structure 234c, 254c, 433c fourth V-shaped ridge structure 234d, 254d scattering particles 242 first optical plate 25, 45 diffusion space 26 optical Sheet 30 Quadrangular pyramid groove 436 V-shaped projection 456 Curved projection 458 Curved groove 459 Reference 16