201007231 九、發明說明： 【發明所屬之技術領域】 ' 本發明涉及一種導光板及其製造方法，以及採用該導 ' 光板之背光模組，尤其涉及一種用於液晶顯示之導光板及 其製造方法，以及採用該導光板之背光模組。 【先前技術】 由於液晶顯示器面板之液晶本身不具發光特性，因而 為達到顯示效果需給液晶顯示器面板提供一面光源裝置， ❹如背光模組。背光模組之作用係向液晶顯示器面板供應亮 度充分且分佈均勻之面光源。目前，背光模組有直下式及 側光式兩種，由於側光式背光模組更易於實現薄型化設 計，使用較為廣泛。 一種習知之側光式背光模組10包括一光源11及一導 光板12。導光板12包括一入光面121、一與該入光面121 相連之出光面122及一與該出光面122相對之反射面123。 入光面121為導光板12之一侧面，光源11與入光面121 _相鄰設置。反射面123上設置有複數網點125，光源11所 發出之光線藉由入光面121進入導光板12内並經由反射面 123反射，而從出光面122出射。反射面123上設置之複數 網點125可使光線發生散射而提升背光模組10之出光均勻 性。網點125 —般藉由印刷法或化學蝕刻法形成於導光板 12表面，但由於形成之網點125較大，加工精度不高，造 成導光板12之網點部分較亮而網點週圍之平面部分則較 暗，而導致導光板12之均光效果較差，於背光模組10之 5 201007231 • ψ % 出光面容易明顯地看見網點。 - 為避免於背光模組Κ)之出光面看見網點，導光板12 .上方通常還需設置-擴散片13，用以對光線進—步散射， 增細對光線進行集光。然而，光線於擴散片 中傳輪時，部分光線會被擴散片13吸收或反 =内而^部分光線損失；並且擴散片13之使用還將增加 =於傳輸過程中之介面數量，從而增加光線傳輸之介面 ❹==線之利用率，㈣光模組1G之出光亮度降低。 =上述狀況’有必要提供—料提高光 高之導先板及其製造方法，—導 及鱼：：導光板’包括入光面、與該入光面相連之出光面 二出光面相對之反射面，該出光面與該反射面之盆中 表面設置有複數網點’該網點大於或等於 ® :、、光滑鏡面，且每一網點之週邊形成有一環形凹槽。201007231 IX. Description of the invention: [Technical field of invention] The present invention relates to a light guide plate and a method of manufacturing the same, and a backlight module using the same, and more particularly to a light guide plate for liquid crystal display and a method of manufacturing the same And a backlight module using the light guide plate. [Prior Art] Since the liquid crystal of the liquid crystal display panel itself does not have a light-emitting property, it is necessary to provide a light source device, such as a backlight module, to the liquid crystal display panel in order to achieve the display effect. The function of the backlight module is to supply a surface light source with sufficient brightness and uniform distribution to the liquid crystal display panel. At present, the backlight module has two types: a direct type and a side light type. Since the edge type backlight module is easier to realize a thin design, it is widely used. A conventional edge-lit backlight module 10 includes a light source 11 and a light guide plate 12. The light guide plate 12 includes a light incident surface 121, a light exit surface 122 connected to the light incident surface 121, and a reflective surface 123 opposite to the light exit surface 122. The light incident surface 121 is one side surface of the light guide plate 12, and the light source 11 is disposed adjacent to the light incident surface 121_. A plurality of dots 125 are disposed on the reflecting surface 123. The light emitted by the light source 11 enters the light guide plate 12 through the light incident surface 121 and is reflected by the reflecting surface 123 to be emitted from the light emitting surface 122. The plurality of dots 125 disposed on the reflecting surface 123 can scatter light to enhance the uniformity of the light output of the backlight module 10. The dot 125 is generally formed on the surface of the light guide plate 12 by a printing method or a chemical etching method. However, since the formed dot 125 is large, the processing precision is not high, and the dot portion of the light guide plate 12 is brighter and the planar portion around the dot is more Dark, and the light-conducting effect of the light guide plate 12 is poor, in the backlight module 10 of 5 201007231 • ψ % light-emitting surface is easy to see the dots. - In order to avoid seeing the dots on the light-emitting surface of the backlight module, the light-guiding plate 12 is usually provided with a diffusion sheet 13 for scattering the light and concentrating the light. However, when the light passes through the wheel in the diffuser, part of the light will be absorbed by the diffuser 13 or the inner part of the light will be lost; and the use of the diffuser 13 will increase the number of interfaces during the transfer, thereby increasing the light. The interface of the transmission ❹== line utilization, (4) the brightness of the light output of the optical module 1G is lowered. = The above situation 'necessary to provide - the guide plate for improving the light height and its manufacturing method, - guide and fish:: light guide plate' includes the light incident surface, and the light exit surface connected to the light incident surface The surface of the illuminating surface and the reflecting surface of the reflecting surface is provided with a plurality of dots which are greater than or equal to ®:, a smooth mirror surface, and an annular groove is formed at the periphery of each dot.
奸：:製2述導光板之方法，包括以下步驟；供-丄基，，利用-镭射光束對該模仁基板之一表面進㈣ "依大形成複數網點結構，其中每一網點結構A 丄為-環形凸起’從而形成一導光板壯;利用該= 模仁注塑成型導光板。 等九扳 如上二種模組，包括光源與導光板。該導光板之特徵 奴所述，且該光源靠近該導光板之入光面。 6 201007231 本發明之導光板用於背光模組時，光線經網點週邊之 環形凹槽調節後’射向網點並使光線發生預定之折射與散 射’而使光線最終沿預定方向出射以提高導光板之出光均 勻性。由於網點之絕大部分表面為光滑鏡面，射向網點之 光線一部分藉由折射從網點上出射，另一部分光線不會因 為發生漫反射而於網點處滯留，而係沿一特定方向被反射 回導光板内’再藉由反射面之反射作用從網點週圍之平面 部分出射’從而使導光板之網點及網點週圍之平面部分亮 度基本一致。同時，由於該導光板之網點藉由鐳射加工而 成，加工精度高，網點大小一致且尺寸較小，使導光板之 均光效果很好，於採㈣導光板之背錢組之出光面不會 看到網點’從而可省略擴散片之使用，進而避免採用擴散 片而產生之光線損失，提升光線利用率。 【實施方式】 下面將結合附圖及較佳實施例對本發明 籲其導光板作進一步之詳細說明 明參見圖2 ’本發明較佳實施例之導光板22為一矩形 明板’其包括入光面221、與入光面 222以及盥出氺；< 出九面 署古％垂〇出先 對之反射面223。出光面222上設 點22^= 225,該複數網點225呈不規則分佈’且該網 光面功""近入光面221之區域排列越疏散，越遠離入 先面221之區域排列越密集。 疋離 明同時參見圖3與圖4，每一網點η 凸起，其球面2251女认—雄 蒞呈邛为球面 1大於或專於50%之表面為光滑鏡面，且 201007231 每一網點225之週邊形成有一環形凹槽2252。本實施例 中，每一球面2251大於或等於90%之表面為光滑鏡面。每 一網點225之最大寬度D小於或等於0.06毫米。 請參見圖5，導光板22之製造方法為：首先提供一模 仁基板200;然後利用一鐳射光束對模仁基板200之一表面 進行蝕刻，依次形成複數網點結構210,其中每一網點結構 210為一凹槽，該凹槽之凹面211上大於或等於50%之表面 為光滑鏡面，且該凹槽之週邊為一環形凸起212。蝕刻完成 @後，即形成一導光板模仁；最後利用該導光板模仁注塑成 型導光板22。導光板22可由聚曱基丙烯酸曱酯、聚碳酸 酯、聚苯乙烯、苯乙烯-曱基丙烯酸曱酯共聚物中之一種或 一種以上之材料注塑成型。 本發明優選採用高頻釔鋁石榴石（YAG)鐳射器發射鐳 射光，鐳射光波長約為1000至1500奈米，優選為1064奈 米。鐳射光束聚焦於模仁基板200上，聚焦點溫度急劇升 @高，聚焦點中心之模仁基板材料被氧化變為粉塵，而於模 仁基板200上形成凹面211;聚焦點邊緣之模仁基板材料則 熔融形成類似火山口之環形凸起212。注塑導光板22時， 凹面211及環形凸起212即於導光板22上相應形成網點225 之球面2251及環形凹槽2252。 另，本發明所採用之鐳射發射器不限於高頻YAG鐳射 器，還可為紅寶石鐳射器、綠寶石鐳射器等；鐳射光波長 可根據實際需要調整，如可為266奈米、355奈米、532奈 米等，波長越小則網點225之最大寬度越小。 8 201007231 請同時參見圖2與圖4,當導光板22用於背光模組時， 光線由入光面221進入導光板22内，當光線傳輸至網點225 時，環形凹槽2252可使光線發生預定之折射與反射，避免 光線直接射出導光板22外，光線經環形凹槽2252調節後 射向球面2251，經由球面2251再次使光線發生折射與散 射，而使光線最終沿預定方向出射以提高導光板22之出光 均勻性。由於球面2251之絕大部分表面為光滑鏡面，射向 球面2251之光線一部分藉由折射從網點225上出射，另一 ®部分光線不會因為發生漫反射而於網點225處滯留，而係 沿一特定方向被反射回導光板22内，再藉由反射面223之 反射作用從網點225週圍之平面部分出射。這樣，導光板 22之網點225以及網點225週圍之平面部分亮度基本一 致。同時由於網點225藉由鐳射加工而成，加工精度高， 大小一致且尺寸較小，使導光板22之均光效果很好，於採 用導光板22之背光模組之出光面不會看到網點225，從而 @可省略擴散片之使用，進而避免採用擴散片而產生之光線 損失，提升光線利用率。 另，呈不規則分佈之網點可有效避免導光板22之出光 面222上產生干涉條紋，網點225於越靠近入光面221之 區域排列越疏散，越遠離入光面221之區域排列越密集則 可進一步提升導光板22之出光均勻性。 請參見圖6，本發明較佳實施例之背光模組20包括光 源21、導光板22、位於導光板22下方之反射片23、位於 導光板22上方之增光片24以及用以定位並保護上述元件 9 201007231 之框架25。光源21為呈線性排列之複數發光二極體，其與 導光板22之入光面相鄰設置。導光板22之出光面222上 設置有網點225。反射片23用以將從導光板22射出之光線 反射回導光板22内，以提高光線利用率。增光片24用以 收斂從導光板22出射之光線，從而提升背光模組20之亮 度。 由於導光板22上之網點225可使光線發生特定之折射 與反射作用，使網點225以及網點225週圍之平面部分之 ®亮度基本一致，使得背光模組20可省略擴散片之使用，而 不會於背光模組20之出光面看到網點225。光線從導光板 22出射後直接進入增光片24中集光後從背光模組20出 射，此過程避免了光線被擴散片吸收及反射造成之損失， 同時避免了光線之一部分介面損失，因此可顯著提高光線 利用率，約提高30%。同時，光線未經擴散片散射而直接 從導光板22進入增光片24，光線分散角度較小，更有利於 ❹增光片24集光，從而提升背光模組20之出光亮度。省略 擴散片還有助於降低背光模組20之成本及減小背光模組 20之厚度。 另，光源21還可為冷陰極螢光燈管等其他線光源。複 數網點225還可設置於反射面223上，或同時設置於出光 面222與反射面223上。網點225之形狀除部分球面凸起 以外，還可有其他變化設計，如圓錐狀凸起或圓臺狀凸起 等。網點225之排佈可根據導光板22及光源21之搭配情 況進行合理設計，如接收光較弱之區域設置較多較密之網 201007231 點225，接收光較強之區域設置較少較疏之網點225。 綜上所述，本發明確已符合發明專利之要件，遂依法 ‘提出專利申請。惟，以上所述者僅為本發明之較佳實施方 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】 〇 圖1係一種習知之背光模組之剖面示意圖。 圖2係本發明較佳實施例之導光板之立體示意圖。 圖3係圖2所示導光板之出光面之局部放大圖。 圖4係圖3所示導光板沿VI_VI線之局部剖視圖。 圖5係製造圖2所示導光板之模仁基板之局部放大圖。 圖6係本發明較佳實施例之背光模組之立體示意圖。 【主要元件符號說明】 導光板 22 ^ 入光面 221 出光面 222 反射面 223 網點 225 球面 2251 環形凹槽 2252 模仁基板 2〇〇 網點結構 21〇 凹面 211 11 201007231 環形凸起 212 背光模組 20 光源 21 反射片 23 增光片 24 框架 25奸:: The method of making the light guide plate comprises the following steps; for the 丄-base, using the -laser beam to the surface of one of the mold base substrates (4) " forming a plurality of dot structures, wherein each dot structure A The crucible is a ring-shaped protrusion to form a light guide plate; the light guide plate is injection molded by the mold. Wait for the nine types of modules, including the light source and the light guide plate. The light guide plate is characterized by a slave, and the light source is adjacent to the light incident surface of the light guide plate. 6 201007231 When the light guide plate of the present invention is used in a backlight module, the light is adjusted through the annular groove around the halftone dot, and then 'shoots toward the mesh point and causes the light to undergo predetermined refraction and scattering' to cause the light to finally exit in a predetermined direction to improve the light guide plate. Light uniformity. Since most of the surface of the dot is a smooth mirror, part of the light that strikes the dot is emitted from the dot by refraction, and the other part of the light is not retained at the dot due to diffuse reflection, but is reflected back in a specific direction. In the light panel, 'the reflection from the reflecting surface is emitted from the plane portion around the dot to make the brightness of the plane of the light guide plate and the plane around the dot substantially the same. At the same time, since the mesh of the light guide plate is processed by laser, the processing precision is high, the size of the dot is uniform and the size is small, so that the uniform light effect of the light guide plate is good, and the light surface of the back light group of the light guide plate is not You will see the dot ', which can omit the use of the diffuser, thus avoiding the loss of light caused by the diffusion sheet and improving the light utilization. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be further described in detail with reference to the accompanying drawings and preferred embodiments. Referring to FIG. 2, the light guide plate 22 of the preferred embodiment of the present invention is a rectangular panel which includes light. The surface 221, the light-incident surface 222, and the exit surface; < The light-emitting surface 222 is provided with a point 22^=225, and the plurality of dots 225 are irregularly distributed and the area of the near-gloss surface 221 is more evacuated, and the farther away from the area of the first surface 221 is arranged. The denser it is.疋明明 See also Figure 3 and Figure 4, each dot η bulge, its spherical surface 2251 female recognition - male 邛 邛 spherical 1 greater than or exclusively for 50% of the surface is a smooth mirror, and 201007231 each dot 225 An annular groove 2252 is formed in the periphery. In this embodiment, the surface of each spherical surface 2251 greater than or equal to 90% is a smooth mirror surface. The maximum width D of each of the dots 225 is less than or equal to 0.06 mm. Referring to FIG. 5, the light guide plate 22 is manufactured by first providing a mold substrate 200; then etching a surface of the mold substrate 200 by using a laser beam to sequentially form a plurality of dot structures 210, wherein each dot structure 210 As a groove, the surface of the concave surface 211 of the groove is greater than or equal to 50%, and the surface is a smooth mirror, and the periphery of the groove is an annular protrusion 212. After the etching is completed @, a light guide plate mold is formed; finally, the light guide plate 22 is injection molded by the light guide plate mold. The light guide plate 22 may be injection molded from one or more materials selected from the group consisting of polydecyl methacrylate, polycarbonate, polystyrene, and styrene-mercapto acrylate copolymer. The present invention preferably employs a high frequency yttrium aluminum garnet (YAG) laser to emit radium light having a wavelength of about 1000 to 1500 nm, preferably 1064 nm. The laser beam is focused on the mold substrate 200, the temperature of the focus point rises sharply @high, the substrate material of the center of the focus point is oxidized to dust, and the concave surface 211 is formed on the mold base substrate 200; the mold base substrate at the edge of the focus point The material then melts to form a crater-like annular projection 212. When the light guide plate 22 is injection molded, the concave surface 211 and the annular protrusion 212 respectively form a spherical surface 2251 of the mesh point 225 and the annular groove 2252 on the light guide plate 22. In addition, the laser emitter used in the present invention is not limited to a high frequency YAG laser, but may also be a ruby laser, an emerald laser, etc.; the laser light wavelength can be adjusted according to actual needs, such as 266 nm, 355 nm. 532 nm, etc., the smaller the wavelength, the smaller the maximum width of the dot 225. 8 201007231 Please also refer to FIG. 2 and FIG. 4 , when the light guide plate 22 is used for the backlight module, the light enters the light guide plate 22 from the light incident surface 221 , and when the light is transmitted to the mesh point 225 , the annular groove 2252 can generate light. The predetermined refraction and reflection prevent the light from directly exiting the light guide plate 22. The light is adjusted by the annular groove 2252 and then directed to the spherical surface 2251. The light is again refracted and scattered through the spherical surface 2251, so that the light finally exits in a predetermined direction to improve the guide. The light uniformity of the light plate 22. Since most of the surface of the spherical surface 2251 is a smooth mirror surface, a part of the light that is incident on the spherical surface 2251 is emitted from the halftone dot 225 by refraction, and the other part of the light is not retained at the halftone dot 225 due to the diffuse reflection, but is tied along the The specific direction is reflected back into the light guide plate 22, and is then emitted from the planar portion around the halftone dot 225 by the reflection of the reflective surface 223. Thus, the brightness of the flat portion around the halftone dot 225 of the light guide plate 22 and the halftone dot 225 is substantially the same. At the same time, since the dot 225 is processed by laser, the processing precision is high, the size is uniform, and the size is small, so that the light-conducting effect of the light guide plate 22 is good, and the light-emitting surface of the backlight module using the light guide plate 22 does not see the dot. 225, thus @ can omit the use of the diffusion sheet, thereby avoiding the light loss caused by the diffusion sheet, and improving the light utilization efficiency. In addition, the irregularly distributed mesh points can effectively prevent interference fringes on the light-emitting surface 222 of the light guide plate 22, and the mesh dots 225 are more scattered in the region closer to the light-incident surface 221, and the denser the regions are farther away from the light-incident surface 221 The light uniformity of the light guide plate 22 can be further improved. Referring to FIG. 6 , a backlight module 20 according to a preferred embodiment of the present invention includes a light source 21 , a light guide plate 22 , a reflective sheet 23 under the light guide plate 22 , a brightness enhancement sheet 24 located above the light guide plate 22 , and a positioning and protection device. Frame 9 of component 9 201007231. The light source 21 is a plurality of light emitting diodes arranged linearly adjacent to the light incident surface of the light guide plate 22. A mesh dot 225 is disposed on the light emitting surface 222 of the light guide plate 22. The reflection sheet 23 reflects the light emitted from the light guide plate 22 back into the light guide plate 22 to improve the light utilization efficiency. The brightness enhancing sheet 24 is used to converge the light emitted from the light guide plate 22, thereby improving the brightness of the backlight module 20. Since the dots 225 on the light guide plate 22 can cause specific refraction and reflection of the light, the brightness of the planes around the dots 225 and the dots 225 are substantially the same, so that the backlight module 20 can omit the use of the diffusion sheet without A dot 225 is seen on the light exit surface of the backlight module 20. After being emitted from the light guide plate 22, the light directly enters the brightness enhancement sheet 24 and is collected from the backlight module 20, thereby avoiding the loss of light absorbed and reflected by the diffusion sheet, and avoiding a part of the interface loss of the light, thereby being remarkable. Improve light utilization by about 30%. At the same time, the light is directly scattered from the light guide plate 22 into the brightness enhancement sheet 24 without being scattered by the diffusion sheet, and the light dispersion angle is small, which is more advantageous for collecting the light from the brightness enhancement sheet 24, thereby improving the light output brightness of the backlight module 20. Omission of the diffusion sheet also helps to reduce the cost of the backlight module 20 and reduce the thickness of the backlight module 20. In addition, the light source 21 can also be another line source such as a cold cathode fluorescent tube. The plurality of dots 225 may also be disposed on the reflecting surface 223 or on the light emitting surface 222 and the reflecting surface 223 at the same time. The shape of the dot 225 may have other variations, such as a conical projection or a truncated projection, in addition to a partial spherical projection. The arrangement of the dots 225 can be reasonably designed according to the combination of the light guide plate 22 and the light source 21. For example, the area where the receiving light is weak is more densely connected to the 201007231 point 225, and the area with stronger receiving light is less dense. Network dot 225. In summary, the present invention has indeed met the requirements of the invention patent, and ‘patent application according to law. However, the above description is only a preferred embodiment of the present invention, and it is not possible to limit the scope of the patent application of the present invention. Equivalent modifications or variations made by persons skilled in the art in light of the present invention are intended to be included within the scope of the following claims. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic cross-sectional view of a conventional backlight module. 2 is a perspective view of a light guide plate in accordance with a preferred embodiment of the present invention. 3 is a partial enlarged view of a light-emitting surface of the light guide plate shown in FIG. 2. 4 is a partial cross-sectional view of the light guide plate of FIG. 3 taken along line VI_VI. Fig. 5 is a partially enlarged view showing the base of the mold for manufacturing the light guide plate shown in Fig. 2. 6 is a perspective view of a backlight module in accordance with a preferred embodiment of the present invention. [Main component symbol description] Light guide plate 22 ^ Light-incident surface 221 Light-emitting surface 222 Reflecting surface 223 Dot 225 Spherical surface 2251 Annular groove 2252 Mold base substrate 2 〇〇 点 dot structure 21 〇 concave surface 211 11 201007231 Ring protrusion 212 Backlight module 20 Light source 21 Reflector 23 Brightener 24 Frame 25
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