200916904 九、發明說明： 【發明所屬之技術領域】 總體而言’本發明有關於導光板⑴ghtguide)和包括導 光板的顯示系統。特別是，本發明有關於將反射片貼合在 5 導光板上。 【先前技術】 光學顯示器，如液晶顯示器（LCD)正變得日益普遍，其 應用於例如行動電話、從手提式個人數位助手（pDA)到膝上 1〇 型電腦的攜帶型電腦設備、攜帶型數位音樂播放器、LCD 台式電腦顯示器、和LCD電視。除應用更加普遍以外，由 於包含LCD的電子器件的生産商提出更小的系統尺寸的要 求’ LCD正在變得更加薄型化。 許多LCD使用背光源來照明LCD的顯示區域。典型的 15 背光源包含平板或楔形的導光板，所述導光板通常由光學 級的透明聚合物材料通過例如注塑等工藝製成。在許多應 用中’背光源包含一個或多個光源，所述光源將發出的光 從導光板的一個或多個側邊耗合（C0Uple)到導光板中。在平 板或楔形導光板中，耦合進入的光通常通過在導光板的頂 20 表面和底表面全内反射在導光板内傳播，直至遇到導致一 为光從導光板出射的一些細微結構（features)。許多背光 源包含反射片，所述反射片用於更有效地利用可能從導光 板的底表面出射的光。 200916904 【發明内容】 ^體而言’本發明有關於貼合型導光板。本發明 貼合型導光板的顯示器和顯示器背光源。 在本發明的一個方式中，貼人 5 15 Ξι::的:ί板’厚度大於衍射條件的黏合 具有折射“ J導先板在選擇波長範圍内 ^ 丰g厚度大於衍射條件的黏合劑層在選摆诂# 範圍内具有折射率nadh。在撰渥^ 增在選擇波長 射牽，丨在選擇波長乾圍内，黏合劑層的折 v光板的折射率，導光板具有第一和第二主 ::並且黏合劑層與導光板的第二主表面貼合。干；型反 點合劑層在與導光板的相對面貼合。干涉型反射片 充分反射在選擇波長範圍内的光。 在本务月的另-個方式中，背光元件包含 入貼合型導光板的入射面的光源，並且1使光射 用的氺與描，人 並且逛包含起光迴圈作 導：：5。貼合型導光板包含厚度大於衍射條件的 :板、厚度大於衍射條件的黏合劑層、和干涉型反射片。 先板在選擇波長範圍内具有折射率％，黏合劑層在選擇 ;長範圍内具有折射率K在選擇波長範圍内，黏合劑声 的折射率小於導光板的折射率。導光板具有第一和第二主 表面’並且黏合劑層與導光板的第二主表面貼合。干涉型 反射片與黏合劑層在與導光板的相對面貼合。干涉型反射 片充刀反射在選擇波長範圍内的光。起光迴圈作用的光學 膜組合（stack)放置在導光板的第一主表面上。 在本發明的另一個方式中，液晶顯示器包含液晶顯示 20 200916904 模組和背光元件。背光元件包含用於將光射入貼合型導光 板的入射面的光源’並且還包含起光迴圈作用的光學膜組 合。貼合型導光板包含厚度大於衍射條件的導光板、厚度 大於衍射條件的黏合劑層和干涉型反射片。導光板在選= 5波長範圍内具有折射率〜，黏合劑層在選擇波長範圍内具 有折射率nadh。在選擇波長範圍β，黏合劑層的折射率小ς 導光板的折射率。導光板具有第一和第二主表面，並且黏 合劑層與導光板的第二主表面貼合。干涉型反射片與點合 〇 _在與導光板的相對面貼合。干㈣反射充分反射在 10選擇波長範圍内的光。起光迴圈作用的光學膜組合⑷ 放置在導光板的第一主表面上。 a從下面的詳細描述中，本發明的這些和其他方面將是 月顯的。然而，上面的概述決不能被理解爲對權利要求主 題的限制，該主題只由後附權利要求書限定，而權利要求 15 書在訴訟中可以修改。 f 【實施方式】200916904 IX. Description of the Invention: [Technical Field to Which the Invention Is Applicable] In general, the present invention relates to a light guide plate (1) ghtguide and a display system including the same. In particular, the present invention relates to attaching a reflective sheet to a 5 light guide plate. [Prior Art] Optical displays, such as liquid crystal displays (LCDs), are becoming increasingly popular for use in, for example, mobile phones, portable computer devices from portable personal digital assistants (PDAs) to laptops, portable devices. Digital music player, LCD desktop monitor, and LCD TV. In addition to applications becoming more prevalent, manufacturers of electronic devices including LCDs have demanded smaller system sizes. LCDs are becoming thinner. Many LCDs use a backlight to illuminate the display area of the LCD. A typical 15 backlight comprises a flat or wedge shaped light guide, which is typically made from an optical grade of transparent polymeric material by processes such as injection molding. In many applications, the backlight contains one or more light sources that illuminate the emitted light from one or more sides of the light guide into the light guide. In a flat or wedge-shaped light guide, the light that is coupled in is generally propagated through the light guide through total internal reflection on the top and bottom surfaces of the top 20 of the light guide until some fine structure that causes light to exit the light guide is encountered. ). Many backlights include a reflective sheet that is used to more efficiently utilize light that may exit from the bottom surface of the light guide. 200916904 SUMMARY OF THE INVENTION The present invention relates to a bonded light guide plate. The display and display backlight of the laminated light guide of the present invention. In one embodiment of the present invention, the adhesive layer of the 5 15 Ξι::: ί plate 'thickness greater than the diffraction condition has a refractive index of the J-lead plate in the selected wavelength range ^ the thickness of the adhesive layer is greater than the diffraction condition Selecting the 诂# range has a refractive index nadh. In the 渥^ increase at the selected wavelength, the refractive index of the adhesive layer of the adhesive layer is selected, and the light guide plate has the first and second main :: and the adhesive layer is bonded to the second main surface of the light guide plate. The dry type anti-dopant layer is bonded to the opposite side of the light guide plate. The interference type reflective sheet sufficiently reflects light in a selected wavelength range. In another mode of the moon, the backlight element includes a light source that enters the incident surface of the light-shielding type light guide plate, and 1 is used to make the light-emitting sputum and the trace, and the person includes the light-returning circle as a guide: 5. The combined light guide plate comprises a thickness greater than a diffraction condition: a plate, a binder layer having a thickness greater than a diffraction condition, and an interference type reflection sheet. The first plate has a refractive index % in a selected wavelength range, and the adhesive layer is selected; the long range has The refractive index K is within the selected wavelength range The refractive index of the adhesive sound is smaller than the refractive index of the light guide plate. The light guide plate has first and second main surfaces ′ and the adhesive layer is adhered to the second main surface of the light guide plate. The interference reflective sheet and the adhesive layer are in contact with each other. The opposite surface of the light guide plate is attached. The interference type reflection sheet fills the light in the selected wavelength range. The optical film stack which acts as a light loop is placed on the first main surface of the light guide plate. In another mode, the liquid crystal display comprises a liquid crystal display 20 200916904 module and a backlight element. The backlight element comprises a light source ' for injecting light into an incident surface of the conformal light guide plate and further comprises an optical film combination for light-returning action The bonding type light guide plate comprises a light guide plate having a thickness larger than a diffraction condition, an adhesive layer having a thickness larger than a diffraction condition, and an interference type reflection sheet. The light guide plate has a refractive index ~ in a wavelength range of selected = 5, and the adhesive layer is in a selected wavelength range. The inside has a refractive index nadh. In the selected wavelength range β, the refractive index of the adhesive layer is smaller than the refractive index of the light guide plate. The light guide plate has the first and second main surfaces, and the adhesive The layer is bonded to the second main surface of the light guide plate. The interference type reflection sheet and the point 〇 are attached to the opposite surface of the light guide plate. The dry (four) reflection sufficiently reflects the light in the selected wavelength range of 10. The light loop is used. The optical film combination (4) is placed on the first major surface of the light guide plate. a These and other aspects of the present invention will be apparent from the following detailed description. However, the above summary is in no way to be construed as a claim The subject matter is limited only by the appended claims, and the claim 15 can be modified in litigation. f [Embodiment]
Li 許多需要高反射率反射鏡的光學産品和器件使用干涉 式的多層薄膜結構。這種多層膜結構可以實現低成本的生 20 =工藝’並且可以設計成在需要的波長範圍内具有高反射 率，所述波長範圍如肉眼可見的光譜或特定的光源的輸出 一“成特又的社測器的局響應度光譜範圍。所述多層膜結 構逛可以在特定的入射光角度範圍内提供所需的反射率。 對於垂直入射和適當角度的入射光’通常可以在特定的波 25長甚至在選定的整個波長範圍内獲得優異的反射率性能。 200916904 這種性能通常可以滿足特定的終端應用的需求。干涉型反 射片，如多層膜干涉型反射片的實例包括在下列專利中描 述’如，美國專利6,208,466(Liu等）、5 825 543 (⑽的成 等）、5,783,120 (Ouderkirk 等）、5,882,774 (Jonza 等）、 5 5,612,820 (8111>恤等）、和5,486,949 (81^111<;等）。如在例如 美國專利申請號11/691769中所描述的，在一些情況下，可 以使用寬角度反射鏡系統提高在寬的波長和角度範圍内的 反射性。 對於一些應用，如掌上型顯示器的背光源，可以使用 10用於反射可見光的雙折射多層膜反射和傳播進入到導光板 的入射面的部分光。一種這樣的雙折射多層膜是可獲自3厘 Company的商標爲vikuiti ESR™(增強型鏡面反射）膜的多 層膜干涉型反射片。通過將ESR膜放置於導光板的下面並被 低折射率的介質如空氣所包圍可以獲得最佳性能，從而使 15 得這些背光具有可接受的光學性能。然而，如果破壞了將 ESR膜周圍的低折射率介質條件，例如ESR膜在上下表面同 時與導光板或顯示器的其他部分接觸，則可能出現光能的 損耗8 本說明書公開了一種在顯示器’例如手持顯示設備中 20 降低來自反射片的光損耗的技術。通過使用光學黏合劑將 反射片黏接到導光板上降低光能損耗。通過這種方式，防 止導光板和反射片的無意接觸’這種接觸可能在接觸區域 中産生由於反射片透光而形成的不必要的光損失（光浪 漏）。選擇具有適當的折射率的光學黏合劑可以減少或消除 200916904 這種不必要的在反射片上發生的透射，如干涉型反射片 詳細來說，「厚度大於衍射條件」的材料指材料厚^ 通常大於光波長’特別是更大的數量級，例如至少靖/ 並且可以是幾百微米或更大。幾何光學可以充分預測或打 述厚度大於衍射條件的光學薄膜的光學性能，如它的反^ 和透射性能。相比之下，干涉光學可以絲充分描述在干 涉型光學膜如多層膜干涉型反射片中的薄膜層 行爲。 巧 干涉型反射片，如多層膜干涉型反射片可以由無機材 ίο料如金屬或氧化物的交替層構成，並且可以是導電或非導 電的反射片。在一些情況下，多層膜干涉型反射片可以由 有機材料製成。在本發明的一個方面中，可以使用折射率 比厚度大於衍射條件的基底材料更低的厚度大於衍射條件 的黏合劑，將聚合物多層膜干涉型反射片如ESR膜黏貼到厚 15度大於衍射條件的基底如導光板上。射入諸如導光板這種 基底材料的光由於全反射被限制在導光板内傳播，從而將 不必要的透射出ESR膜的光損失減到最少。光在導光板内傳 播，可以通過例如與在本說明書中所描述的微結構 (extraction features)的相互作用，在所需要的位置上將光線 2〇 引出導光板。 根據周圍介質的不同，入射到多層膜干涉型反射片如 ESR表面的光，可能會發生洩漏。隨著入射角從垂直於多層 膜干涉型反射片的表面（0。入射角）的方向增大，可以達到 “洩漏角”。對於本文的詳細描述來說，洩漏角是指在該角 200916904 度或者大於該角度時大部分入射到多層膜干涉型反射片上 的光能發生透射的角度。在小於茂漏角的入射角，大部分 光由多層膜干涉型反射片表面反射。线漏角可以取決於多 層膜干涉型反射片中的材料和膜層厚度、反射片周圍的介 5質:和入射光的波長。當多層膜干涉型反射片周圍的折射 率增加’在漏角顯著減小（即，多層膜干涉型反射片茂漏 更多的入射光）。應當注意到，多層膜干涉型反射片的兩個 外表面可以處於折射率不同的介質材料中。反射片的茂漏 角可能受到每-種不同材料的影響；然而，如果一種材料 H)是空氣，則在多層膜干涉型反射片内傳播並且入射到空氣 表面上的光，會在具有較高洩漏角的表面上發生反射。 夕層膜干涉型反射片的洩漏角減小（通過浸入在折射 率更高的介質中），會對顯示器的亮度和均勻性産生不利的 影響。例如，當ESR膜與背光中的導光板發生光學意義上的 15接觸時，在導光板中原本以大的角度正常傳播的光無法發 生全反射（F-TIR) ’因而被耦合到ESR膜中。除非另一種物 體也與發生光耦合區域中的ESR膜的另一個表面發生接 $，否則這種麵合不會産生报大的影響。另—種物體可以 疋顯不器外框的一部分、一片灰塵、液體或任何其他的碎 2〇屑。當發生這種情況時，耦合到ESR膜中的光會透射出 ESR，並在顯示器的背面損失掉。這種光損耗會産生暗點並 且降低顯示器的均勻性。 在些情況下’導光板和ESR膜反射片在顯示器背光 _是通過空氣間If隔開@ ’並且可以使用環繞導光板的間 200916904 隔體（spacer )保持空氣間隙。然而，間隔體可能無法一直 維持空氣間隙，並且一些碎屑也可能進入導光板和反射片 之間的間隙。這種碎屑可能導致光耦合和光洩漏，從而導 致顯示器出現暗點並且破壞均勻性。此外，導光板和反射 5 片可能相互獨立地移動，並且可能發生變形或翹曲。由例 如溫度變化所導致的翹曲可能導致反射片和導光板相互接 觸，從而引起光洩漏。在一些情況下，濕度和靜電的變化 也可能導致光耦合和光洩漏。 ('} 本發明使用折射率（nadh)小於導光板的折射率（ng)的厚 10 度大於衍射條件的黏合劑層將干涉型反射片如ESR膜黏貼 到厚度大於衍射條件的導光板上。可以選擇適當折射率差 使得基本上全部射入導光板的光保持在導光板中，並且不 會以大於洩漏角的入射角進入ESR膜。還可以選擇nadh，使 得被迴圈的光（例如，從棱鏡膜，如VikuitiTM Brightness 15 Enhancement Film “BEF” 或 Thin Brightness Enhancement Film “TBEF”，或反射式偏振片如 Vikuiti™ Dual Brightness Enhancement Film “DBEF”，可獲自 3M Company)通過導光 c 板和黏合劑層以後，可以以小於洩漏角的角度入射到ESR 膜上，從而使其被再次朝向顯示器反射。 20 導光板可以具有任何需要的尺寸或形狀，並且可以具 有均勻的厚度如平板，或可以是具有一定的傾角，如楔形。 這種導光板可以應用在例如行動電話、膝上型電腦、電視 或其他應用中的液晶顯示器（LCD)的背光源中。可以將微結 構可以設計在導光板的前表面或其他導光板上或導光板中 11 200916904 的位置上，以使光從導光板内向要被照亮的液晶板或其他 部件出射。 所述導光板可以在與貼合的反射片相對的一侧上具有 微总構，從而使光以預定的角度被導向觀察者。可以在例 5 如美國專利 M45,212 (Gardiner等）和 7,223,005 (Lamb等）中 找到微結構的實例，並且在美國申請號u/421，241中也可以 找到。微結構可以是被設計成使光從導光板出射的凹槽、 小透鏡（lenslet)、或其他微結構。可以使用幾種方法將微結 構製作在導光板上，所述方法包括但不限於：鑄造、壓花、 10微複製、印刷、燒姓、姓刻、和本領域中已知的其他方法。 本發明還以單個部件的形式提供導光板和反射片，如 貼合型導光板，從而減少背光源部件的數量和背光裝配者 的成本。冑導光板貼合到&射片上可以防止碎屑進入兩個 表面之間而導致在顯示均勻性方面的缺陷。適當地選擇導 15光板和黏合劑折射率可以保持光在導光板内的傳播效率， 並且防止光以大於洩漏角的角度進入反射片。兩個部件的 貼合還可以減少每個部件的翹曲，從而提高環境性能和穩 定性。 對於该詳細描述為，選擇波長範圍可以表示可見光或 20近可見光（例如，400_70〇ηηι波長）、近紅外光（例如， 700-100〇nm、700_1400nm、或 7〇〇5〇〇〇nm，波長範圍的選 擇有時取決於使用的檢測器或傳播介質）、或可見和近紅外 光組合、或t們的一部分。纟他範圍也彳以是選擇的波長 範圍。例如，如果在具有窄帶發射器如㈣或雷射的系統 12 200916904 中使用貼合型導光板’則選擇波長範圍可以較窄（例如， lOOnm、50nm、l〇nm或更小）。對於在用於液晶顯示器（LCD) 或其他顯示器的照明系統如背光源中使用的貼合型導光 板’選擇波長範圍可以更寬（例如，4〇〇_8〇〇 nm、 5 400-900nm、400-1000nm、40(M20〇nm、400-1400nm、 400-1600nm、或 400-1700nm)。 多層膜干涉型反射片典型地由數十、數百或數千層微 結構組成，這些微層由以光學材料“a，，和“b，，相交替的形式組 、 成，例如四分之一波長膜堆。光學材料“a，b，，可以是已知在 10干涉膜堆結構中具有應用的任何適合的材料，無論其是無 機的（如Ti〇2、Si〇2、CaF或其他適合的材料），還是有機的， 例如聚合物（例如，聚萘二曱酸乙二醇酯（pEN)、聚曱基丙 烯酸曱醋（PMMA)、聚對苯二曱酸乙二醇醋（PET)、丙稀酸 類和其他適合的材料）。所述多層膜可以具有全無機材料、 15全有機材料或無機/有機材料相混合的結構。所述多層膜體 可以包含更多的材料，而不僅是材料“a，b”，例如在疊層體 中可以包含另外的材料“c”、“d”等。膜層可以是各向同性 的也可以疋雙折射膜層，或者是各向同性微層和雙折射 層的組合。具有雙折射性質的多層膜可以用於：對稱反射 20系統，能夠基本上相同地反射任何偏振態的垂直入射光； 或不對稱反射系統，對於一種偏振態的垂直入射光具有高 反射率而對於正交的偏振態的垂直入射光具有較低的反射 率。 每層薄膜的光學厚度（物理厚度乘以折射率）通常小於 13 200916904 一個光波長。這些膜層以周期的形式排列，稱爲光學重復 單元（ORU)，例如其中ORU的光學厚度是在選擇波長範圍内 的光的波長的二分之一。這些膜層使光的相長干涉或相消 干涉變得可能，所述光的相長或相消干涉是造成多層膜的 5 反射和透射性能隨波長改變的原因。ORU可以是兩層結構 “ab”，但是其他排列也可以，如在美國專利5,103,337 (Schrenk等）、3,247,392 (Thelen)、5,360,659 (Arends等）和 7,019,905 (Weber)中論述的排列。在需要時，ORU的光學 厚度可以沿著多層膜的厚度維度上發生漸變以加寬反射波 10 帶。所述多層膜結構在其整個範圍内並非一定要是平坦或 平面的，如果需要可以將其成形、模制或壓花成非平面形 狀。然而，至少在局部上可以認爲膜層結構基本上平行於 局部的x-y座標平面。 在一些情況下，可以通過選擇折射率適合的替換材 15 料、每層薄膜的厚度分佈和膜層總數，得到具有例如以下 特性的多層膜：反射帶在整個可見區延伸，並且延伸到近 紅外區，具有陡峭的左右譜帶邊沿，並且至少在整個可見 光範圍内（並且對於一些應用，也在整個近紅外區中）具有至 少70%、80%、90%或更高平均反射率。可參考例如由3M公 20 司出售的利用雙折射多層膜結構的Vikuiti™ Enhanced Specular Reflector (ESR)膜。ESR可以在整個可見光範圍内 具有大於98%的反射率。 多層膜可以完全由聚合物組成，並且可以通過共擠壓 法和拉伸法製備以在微層中引起適當的雙折射，從而提高 14 200916904 反射率。在一些情況下，多層膜可以包含或者全部由無機 材料組成，並且可以通過真空蒸鍍技術製備。對於使用無 機材料的雙折射多層膜，參考美國專利6,59〇,7〇7(貿外以）。 現在我們轉向圖1，圖丨顯示了根據本發明的一個方面 5的具有背光源的顯示器200的一個實施方案。具有背光源的 顯示器200包含背光模組250和LCD模組260。背光模組25〇 包3彦光源220和可選的具有光迴圈作用的數層光學膜組 合240，所述具有光迴圈作用的光學膜組合24〇被設置在背 光源220和LCD模組260之間。 10 背光22〇包含貼合型導光板210和光源218。貼合型導光 板210包含反射片216’所述反射片216是使用厚度大於衍射 條件的黏合劑層214黏合到厚度大於衍射條件的導光板212 上的。光源218被置於導光板212的側邊211，使得發出的光 能射入到導光板内。光源218可以是任何光源，包括例如冷 15 陰極螢光燈（CCFL)和發光二極體（LED)。在一些情況下， LED光源是較佳的光源。 反射片216可以是對於可見光具有例如9〇%或更高反射 率的任何類型反射片。在一些情況下’可以使用金屬型反 射片和干涉型反射片如多層膜干涉型反射片。在一些情況 20 下，可以使用聚合物多層膜干涉型反射片，如ESR膜。 厚度大於衍射條件的導光板212可以由玻璃或聚合物 材料如熱塑性或熱固性聚合物製成。在一些情況下，適用 於厚度大於衍射條件的導光板212的熱塑性塑膠是聚碳酸 酯，但是可以使用任何具有適當的光透射性能的熱塑性聚 15 200916904 合物。厚度大於衍射條件的導光板212可以是均聚物、共聚 物或共混聚合物。共混聚合物的折射率通常稱爲「有效折 射率」，該折射率可以用實驗方法測定。對於本公開來說， 厚度大於衍射條件的導光板212的折射率是在導光板的表 5 面測量的折射率。在一些情況下，可以將熱固性材料，如 輻射固化性丙烯酸酯或曱基丙烯酸酯等用於厚度大於衍射 條件的導光板212。厚度大於衍射條件的導光板212可以是 柔性導光板或剛性導光板。在例如美國專利申請號 11/421,241中描述了柔性導光板。 10 進入厚度大於衍射條件的導光板212的側邊211的光以 出射光230的形式從背光源220出射，並且被導向具有光迴 圈作用的光學膜組合240。具有光迴圈作用的光學膜組合 240用來進一步調節進入LCD模組260的光，並且更有效地 利用光以提高具有背光源的顯示器200的亮度和均勻性。出 15 射光230從前表面222離開背光源220並且進入具有光迴圈Li Many optical products and devices that require high reflectivity mirrors use an interferometric multilayer film structure. Such a multilayer film structure can achieve a low cost of production 20 and can be designed to have a high reflectance in the desired wavelength range, such as the spectrum visible to the naked eye or the output of a particular light source. The local responsiveness spectral range of the detector. The multilayer film structure provides the desired reflectivity over a range of specific incident light angles. For normal incidence and normal angle of incident light 'typically at a particular wave 25 Excellent reflectivity performance even over selected wavelength ranges. 200916904 This performance is typically sufficient for specific end applications. Examples of interference-type reflective sheets, such as multilayer film interference-type reflective sheets, are described in the following patents. ', for example, U.S. Patent Nos. 6,208,466 (Liu et al.), 5 825 543 ((10), 5,783,120 (Ouderkirk, etc.), 5,882,774 (Jonza et al), 5 5,612,820 (8111>shirts, etc.), and 5,486,949 (81^111<; A wide angle mirror system can be used to improve in some cases, as described in, for example, U.S. Patent Application Serial No. 11/691,769. Reflectivity in the range of wavelengths and angles. For some applications, such as backlights for handheld displays, a portion of the light entering the incident surface of the light guide can be reflected and propagated using a birefringent multilayer film for reflecting visible light. The birefringent multilayer film is a multilayer film interference type reflective sheet available from the 3 PCT Company under the trademark vikuiti ESRTM (Enhanced Specular Reflection) film by placing the ESR film under the light guide plate and being low refractive index medium. The best performance can be achieved by encircling the air, so that these backlights have acceptable optical properties. However, if the low refractive index media conditions surrounding the ESR film are broken, such as the ESR film on the upper and lower surfaces simultaneously with the light guide or Loss of light energy may occur when other parts of the display are in contact. 8 This specification discloses a technique for reducing the loss of light from a reflective sheet in a display, such as a handheld display device. 20. By using an optical adhesive, the reflective sheet is bonded to the guide. Reduce the loss of light energy on the light plate. In this way, prevent the unintentional contact between the light guide plate and the reflective sheet. The contact may cause unnecessary light loss (light leakage) due to light transmission of the reflective sheet in the contact area. Selecting an optical adhesive having an appropriate refractive index may reduce or eliminate the unnecessary occurrence of the 200916904 on the reflective sheet. Transmittance, such as interference-type reflective sheet In detail, a material having a "thickness greater than diffraction condition" means that the material thickness ^ is generally greater than the wavelength of light 'especially larger orders of magnitude, such as at least jing/ and may be several hundred microns or more. Geometric optics can adequately predict or describe the optical properties of optical films that are thicker than diffraction conditions, such as their inverse and transmission properties. In contrast, interference optics can fully describe the behavior of thin film layers in interference-type optical films such as multilayer film interference-type reflective sheets. The interference type reflection sheet, such as a multilayer film interference type reflection sheet, may be composed of an alternating layer of an inorganic material such as a metal or an oxide, and may be a conductive or non-conductive reflection sheet. In some cases, the multilayer film interference type reflection sheet may be made of an organic material. In one aspect of the present invention, a polymer multilayer film interference type reflective sheet such as an ESR film may be adhered to a thickness of 15 degrees larger than diffraction by using a binder having a refractive index lower than that of a substrate material having a thickness greater than that of a diffraction condition. The substrate of the condition is as on the light guide plate. Light incident on a substrate material such as a light guide plate is confined within the light guide plate due to total reflection, thereby minimizing unnecessary light loss transmitted through the ESR film. Light is propagated within the light guide plate and the light can be directed out of the light guide plate at a desired location by, for example, interaction with the extraction features described in this specification. Depending on the surrounding medium, light incident on a multilayer film interference type reflective sheet such as the surface of the ESR may leak. The "leakage angle" can be reached as the incident angle increases from the direction perpendicular to the surface (0. incident angle) of the multilayer film interference type reflection sheet. For the detailed description herein, the leak angle refers to the angle at which most of the light energy incident on the multilayer film interference type reflection sheet is transmitted at or above the angle of 200916904 degrees. At an angle of incidence less than the leakage angle, most of the light is reflected by the surface of the multilayer film interference type reflector. The line drain angle may depend on the material and film thickness in the multilayer film interference type reflective sheet, the dielectric around the reflective sheet: and the wavelength of the incident light. When the refractive index around the multilayer film interference type reflection sheet is increased, the leakage angle is remarkably reduced (i.e., the multilayer film interference type reflection sheet leaks more incident light). It should be noted that the two outer surfaces of the multilayer film interference type reflection sheet may be in a dielectric material having a different refractive index. The leakage angle of the reflective sheet may be affected by each of the different materials; however, if one material H) is air, the light propagating within the multilayer film interference type reflective sheet and incident on the air surface will be higher. Reflection occurs on the surface of the leak angle. The reduced leakage angle of the eigen film interference type reflection sheet (by immersion in a medium having a higher refractive index) adversely affects the brightness and uniformity of the display. For example, when an ESR film is optically contacted with a light guide plate in a backlight, light that normally propagates at a large angle in the light guide plate cannot undergo total reflection (F-TIR)' and is thus coupled into the ESR film. . This face does not have a large influence unless another object is also connected to the other surface of the ESR film in the photo-coupled region. Another type of object can show a part of the outer frame, a piece of dust, liquid or any other broken pieces. When this happens, light coupled into the ESR film is transmitted out of the ESR and lost on the back side of the display. This loss of light creates dark spots and reduces the uniformity of the display. In some cases, the light guide plate and the ESR film reflection sheet are separated by @ ’ between the air and the air gap can be maintained by using the 200916904 spacer surrounding the light guide. However, the spacer may not maintain the air gap at all times, and some debris may enter the gap between the light guide plate and the reflection sheet. Such debris can cause optical coupling and light leakage, which can cause dark spots on the display and destabilize the uniformity. In addition, the light guide plate and the reflective sheet 5 may move independently of each other and may be deformed or warped. Warpage caused by, for example, temperature changes may cause the reflection sheet and the light guide plate to contact each other, thereby causing light leakage. In some cases, changes in humidity and static electricity can also cause optical coupling and light leakage. ('} The present invention uses an adhesive layer having a refractive index (nadh) smaller than the refractive index (ng) of the light guide plate and having a thickness of 10 degrees larger than the diffraction condition to adhere an interference type reflection sheet such as an ESR film to a light guide plate having a thickness larger than the diffraction condition. The appropriate refractive index difference can be selected such that substantially all of the light incident on the light guide plate remains in the light guide plate and does not enter the ESR film at an angle of incidence greater than the leakage angle. Nadh can also be selected to cause the light to be looped (eg, From prismatic films such as VikuitiTM Brightness 15 Enhancement Film “BEF” or Thin Brightness Enhancement Film “TBEF”, or reflective polarizers such as VikuitiTM Dual Brightness Enhancement Film “DBEF”, available from 3M Company) through the light guide c-plate and After the adhesive layer, it can be incident on the ESR film at an angle less than the leak angle so that it is again reflected toward the display. 20 The light guide plate can have any desired size or shape and can have a uniform thickness such as a flat plate, or can It has a certain inclination, such as a wedge shape. This light guide can be applied to, for example, a mobile phone, a laptop, a television. Or a backlight of a liquid crystal display (LCD) in other applications. The microstructure can be designed on the front surface of the light guide plate or on other light guide plates or in the position of the light guide plate 11 200916904, so that the light is directed from the inside of the light guide plate. The illuminated liquid crystal panel or other component is emitted. The light guide plate may have a micro total configuration on a side opposite to the attached reflective sheet, so that the light is directed to the observer at a predetermined angle. Examples of microstructures are found in U.S. Patent Nos. M45,212 (Gardiner et al.) and 7,223,005 (Lamb et al.) and are also found in U.S. Application Serial No. 4,421,241. The microstructures can be designed to emit light from a light guide. Grooves, lenslets, or other microstructures. Microstructures can be fabricated on the light guide using several methods including, but not limited to, casting, embossing, 10 microreplication, printing, burning , surnames, and other methods known in the art. The present invention also provides a light guide plate and a reflective sheet in the form of a single component, such as a conformable light guide plate, thereby reducing the number of backlight components and backlighting The cost of the assembler. 胄 The light guide plate is attached to the & film to prevent debris from entering between the two surfaces and causing defects in display uniformity. Proper selection of the 15th plate and the refractive index of the adhesive can keep the light in place. The efficiency of propagation within the light guide plate, and prevents light from entering the reflective sheet at an angle greater than the leak angle. The fit of the two components can also reduce the warpage of each component, thereby improving environmental performance and stability. The selected wavelength range may represent visible light or 20 near visible light (for example, 400_70 〇ηηι wavelength), near-infrared light (for example, 700-100 〇 nm, 700 1400 nm, or 7 〇〇 5 〇〇〇 nm, and the selection of the wavelength range sometimes depends on Detector or propagation medium used, or combination of visible and near-infrared light, or part of t.纟 His range is also the wavelength range of choice. For example, if a conformal type light guide plate is used in a system having a narrow band emitter such as (4) or laser 12 200916904, the selected wavelength range may be narrower (e.g., 100 nm, 50 nm, 10 nm or less). For a suitable type of light guide plate used in an illumination system such as a backlight for a liquid crystal display (LCD) or other display, the wavelength range can be selected to be wider (for example, 4 〇〇 _8 〇〇 nm, 5 400-900 nm, 400-1000 nm, 40 (M20 〇 nm, 400-1400 nm, 400-1600 nm, or 400-1700 nm). Multilayer film interference type reflective sheets typically consist of tens, hundreds or thousands of layers of microstructures consisting of In the form of optical materials "a,, and "b, alternating, such as a quarter-wave film stack. Optical materials "a, b," may be known to have applications in a 10 interference film stack structure. Any suitable material, whether inorganic (such as Ti〇2, Si〇2, CaF or other suitable materials), or organic, such as a polymer (for example, polyethylene naphthalate (pEN) ), polyacrylic acid vinegar (PMMA), polyethylene terephthalate (PET), acrylic acid and other suitable materials. The multilayer film may have all inorganic materials, 15 all organic materials Or a structure in which an inorganic/organic material is mixed. The multilayer film body may contain more Material, not only material "a, b", for example, may include additional materials "c", "d", etc. in the laminate. The film layer may be isotropic or birefringent film layer, or Is a combination of an isotropic microlayer and a birefringent layer. A multilayer film having birefringence properties can be used for: a symmetric reflection 20 system capable of reflecting substantially perpendicularly incident light of any polarization state; or an asymmetric reflection system, for A normally incident light of one polarization state has a high reflectivity and a low reflectivity for a normally incident light of an orthogonal polarization state. The optical thickness (physical thickness multiplied by the refractive index) of each film is usually less than 13 200916904 These layers are arranged in a periodic pattern called an optical repeating unit (ORU), for example where the optical thickness of the ORU is one-half the wavelength of the light in the selected wavelength range. These layers cause the constructive interference of the light. Or destructive interference becomes possible, the constructive or destructive interference of the light is responsible for the 5 reflection and transmission properties of the multilayer film as a function of wavelength. The ORU can be a two-layer structure "ab ", but other arrangements are also possible, such as those discussed in U.S. Patent Nos. 5,103,337 (Schrenk et al), 3,247,392 (Thelen), 5,360,659 (Arends et al.), and 7,019,905 (Weber). The optical thickness of the ORU can be varied along multiple layers. A gradual change in the thickness dimension of the film is used to widen the reflected wave band 10. The multilayer film structure does not necessarily have to be flat or planar throughout its extent, which may be shaped, molded or embossed into a non-planar shape if desired. However, at least in part, it is believed that the film structure is substantially parallel to the local xy coordinate plane. In some cases, a multilayer film having, for example, the following characteristics can be obtained by selecting a replacement material 15 having a suitable refractive index, a thickness distribution of each film, and a total number of film layers: the reflection band extends throughout the visible region and extends to the near infrared The zone, with steep left and right band edges, has an average reflectance of at least 70%, 80%, 90% or higher, at least throughout the visible range (and for some applications, also throughout the near infrared region). For example, a VikuitiTM Enhanced Specular Reflector (ESR) film using a birefringent multilayer film structure sold by 3M Corporation can be referred to. ESR can have a reflectivity greater than 98% over the entire visible range. The multilayer film may be composed entirely of a polymer and may be prepared by a co-extrusion method and a stretching method to induce appropriate birefringence in the microlayer, thereby improving the reflectance of 14 200916904. In some cases, the multilayer film may comprise or consist entirely of inorganic materials and may be prepared by vacuum evaporation techniques. For birefringent multilayer films using inorganic materials, reference is made to U.S. Patent No. 6,59,7,7 (External Trade). Turning now to Figure 1, an embodiment of a display 200 with a backlight in accordance with an aspect 5 of the present invention is shown. The display 200 with backlight includes a backlight module 250 and an LCD module 260. The backlight module 25 includes a light source 220 and an optional optical layer combination 240 having a photo-loop effect. The optical film assembly 24 having a photo-loop effect is disposed on the backlight 220 and the LCD module. Between 260. The backlight 22 includes a bonding type light guide plate 210 and a light source 218. The bonding type light guide plate 210 includes a reflection sheet 216'. The reflection sheet 216 is bonded to the light guide plate 212 having a thickness larger than a diffraction condition using an adhesive layer 214 having a thickness larger than a diffraction condition. The light source 218 is placed on the side 211 of the light guide plate 212 so that the emitted light can be incident into the light guide plate. Light source 218 can be any light source including, for example, a cold 15 cathode fluorescent lamp (CCFL) and a light emitting diode (LED). In some cases, an LED light source is the preferred source of light. The reflective sheet 216 may be any type of reflective sheet having a reflectance of, for example, 9 〇% or higher for visible light. In some cases, a metal type reflective sheet and an interference type reflective sheet such as a multilayer film interference type reflective sheet can be used. In some cases 20, a polymeric multilayer film interference type reflective sheet such as an ESR film can be used. The light guide plate 212 having a thickness larger than the diffraction condition may be made of a glass or a polymer material such as a thermoplastic or thermosetting polymer. In some cases, the thermoplastic plastic suitable for the light guide plate 212 having a thickness greater than the diffraction condition is polycarbonate, but any thermoplastic poly 15 200916904 compound having appropriate light transmission properties can be used. The light guide plate 212 having a thickness greater than the diffraction condition may be a homopolymer, a copolymer or a polymer blend. The refractive index of the polymer blend is often referred to as the "effective refractive index" which can be determined experimentally. For the present disclosure, the refractive index of the light guide plate 212 having a thickness larger than the diffraction condition is the refractive index measured on the surface of the light guide plate. In some cases, a thermosetting material such as radiation curable acrylate or methacrylate may be used for the light guide plate 212 having a thickness larger than the diffraction condition. The light guide plate 212 having a thickness larger than the diffraction condition may be a flexible light guide plate or a rigid light guide plate. Flexible light guides are described in, for example, U.S. Patent Application Serial No. 11/421,241. 10 Light entering the side 211 of the light guide plate 212 having a thickness larger than the diffraction condition is emitted from the backlight 220 in the form of the outgoing light 230, and is guided to the optical film combination 240 having the optical loop effect. An optical film assembly 240 having a photo-loop effect is used to further adjust the light entering the LCD module 260 and to more efficiently utilize light to increase the brightness and uniformity of the display 200 having the backlight. The exiting light 230 exits the backlight 220 from the front surface 222 and enters the optical loop
作用的光學膜組合240。光學膜組合240可以包含一對相交 的BEF棱鏡膜244，棱鏡膜244的棱鏡面朝向LCD模組260。 如所顯示的，光學膜組合還可以包含可選的散射片242和可 選的DBEF反射式偏振片246,它們被置於在相交的BEF棱鏡 20 膜244的兩側。可以將可選的散射片242放置在相交的BEF 棱鏡膜244和背光源220之間。在一些情況下，可選的具有 光迴圈作用的光學膜組合240可以另外包含其他用於進一 步調節光的膜片，如散射片、濾光片等。進入具有光迴圈 作用的光學膜組合240的一部分出射光230能夠在朝向LCD 16 200916904 模組260的方向上透射出該光學膜組合。進入光學膜組合 240的另一部分出射光230作爲再迴圈光235穿過前表面222 返回到背光源220中。如在別處所描述的，再迴圈光235進 入貼合型導光板210的前表面222,並且通過厚度大於衍射 5 條件的導光板212傳播。再迴圈光235最終由反射片216再次 反射向前表面222。 可以使用幾種不同類型的厚度大於衍射條件的黏合劑 層214，例如乾膜熱熔性黏合劑、乾膜壓敏黏合劑' 輻射固 化性黏合劑或溶劑基黏合劑組裝貼合型導光板21 〇。厚度大 10 於衍射條件的黏合劑層214的折射率小於導光板212的折射 率。在一些情況下’折射率之差大於〇 〇〇5，例如大於〇 〇1、 0.1、0.2或以上。 所述黏合劑可以在導光板212和反射片216之間形成連 續或不連續層。在一些情況下，厚度大於衍射條件的黏合 15 20 劑214的連續層可以保證顯示器的均勻性，並且提高背光的 性能。對於這種詳細描述來說，「連續層」指該層基本上 覆蓋厚度大於衍射條件的導光板212和反射片216之間的整 個空間’巾「*連續層」彳旨在厚度大於衍射條件的導光板 212和反射片216之間的空間的至少某些部分沒有被該層所 覆蓋。在-些情況下，例如通過在厚度大於衍射條件的導 光板212或反射片216上沈積不連續的黏合劑圖案，可以使 厚度大於衍射條件的黏合劑214不連續。在一些情況下，可 以使用均句的不連續黏合劑圖案，如均勻分佈^導光板1 的多個黏合劑部分。在-些情況下，不連續塗層在遠小於 17 200916904 導光板尺寸的範圍内是不連續的，而在使用導光板時，黏 合劑層的圖案是不可見的。 圖2顯示了光在貼合型導光板21〇中傳播的光路。如在 圖2中由L〇所示’光源218將光以多個角度射入到厚度大於 5 衍射條件的導光板212的側邊211。厚度大於衍射條件的導 光板212的側邊211與折射率n=l的空氣形成介面。射入到導 光板212中的光線L〇在導光板212内以小於側邊211的法線 的臨界角ecg的角度開始傳播。爲簡單起見，在下面只論述 C ' 朝厚度大於衍射條件的導光板212和厚度大於衍射條件的 10黏合劑214之間的介面213傳播的那些光線，所述光線在圖2 中疋以光線L顯示的。然而，應理解，射入的光線也可以朝 導光板212的前表面222傳播’在前表面222經過全反射，而 在導光板212内繼續以小於側邊211的法線的臨界角ecg的角 度傳播。 15 如在圖2中所示’光線L中的一些如光線通過TIR反射 回到導光板212中。光線L中的一些如光線12被折射到黏合劑 ， 層214中。由0cga=arcsin(nadh/ng)得到介面213的臨界角，並 且導光板212的折射率大於黏合劑層214的折射率。光線L 以大於ecga的角度與介面213相交，因此被反射回到厚度大 20 於衍射條件的導光板212中。光線12以小於0cga的角度與介面 213相交’因此被折射到厚度大於衍射條件的黏合劑214 中。在前表面222爲空氣介面的情況下，光線h在厚度大於 何射條件的導光板212内以大於兩個介面的臨界角的角度 傳播’因此在厚度大於衍射條件的導光板212内經歷全反 18 200916904 射。 在-些情況下’入射到介面如前表面222的光在該介面 處或附近與起出光作用的微結構(在圖2中沒有顯示），從而 導致至少一部分光從導光板以圖^所示的出射光230的形 5式出射。可以引起光出射的微結構可以是在本說明書中別 f公的引出特徵中的任何一種。例如，微結構可以位於 前表面222、介面213、導光板212的内部或它們的組合。 所述光線可以在厚度大於衍射條件的導光板212内反 射數百次。由此，射入導光板中的光L在第一次相交時折射 10進入黏合劑層214中的那部分（丨2)可以是在導光板内傳播的 全部光中的一小部分。折射到黏合劑層214中的光線匕通過 黏合劑層214傳播至反射片216,並且通過該反射片向前表 面222反射。 如果每一層的相對折射率遵循總的關係：（導光板212 15 的折射率）2(在反射片216内的最低折射率）^(黏合劑層 214的折射率），則光線l2可以被反射片216反射。在不滿足 不等式的情況下，一部分光線12可以透射穿過反射片216, 特別是在與非空氣的介質環繞在反射片216兩侧時。 與光線L〇進入邊緣211的方式類似，再迴圈光235以多 20 個角度進入導光板212的前表面222。導光板212的前表面 222與空氣也形成介面，因此光線在前表面222的法線的臨 界角ecg以内在導光板212内傳播。一部分再迴圈光235可以 在介面213經歷TIR，並且另一部分可以以對光線L所述的方 式被折射進入黏合劑層214中。然而，因爲ecg<ecga，大部分 19 200916904 將被折射到厚度大於衍射條件的黏合劑層214中，然後通過 反射片反射向前表面222反射。 現在將在下列說明性實施例中描述示例性實施方案， 在所述實施例中，除非另外說明，否則所有部分和百分比 5 是以重量計的。 實施例 實施例1:來自使用和不使用層壓的聚碳酸酯導光板的光 損耗 10 使用〜3mil (.075 mm)厚的光學黏合劑（Opt-1層塵黏合 劑，也稱爲Bonding Systems Division 9483黏合劑，可獲自 3M Company)，將20mil (0.51mm)厚的薄膜型聚碳_酸醋導光 板（LEXAN®聚碳酸酯膜 8010，可獲自 GE Polymershapes， Seattle WA)黏貼到一片Vikuiti ESR™薄膜（可獲自3M 15 Company)上。聚碳酸S旨導光板的折射率爲1.586，而所述光 學黏合劑的折射率爲1.47。使用台式（benchtop)層壓機 (Catena 35，可獲自 General Binding Corporation，Northbrook IL)，在室溫以1.5英呎/分鐘（0.76 cm/秒）進行貼合。’然後將 貼合樣品和未貼合的薄膜型聚碳酸酯導光板切割成約6cm 20 寬和3 0cm長度的樣品用於測試。 使用光源和積分球測定貼合樣品和未貼合樣品的總光 損耗（由於洩漏、吸收和散射）。使用擴束器擴展543nm的雷 射，然後通過枉面透鏡將其變爲平行光束，然後聚焦在導 光板邊緣上。通過積分球捕獲穿過3〇cm長導光板並且由其 25 遠邊出射的光。使用連接到積分球上的光電探測器測量光 20 200916904 強度。然後將膜削減5 cm，並且重復該過程直至最初的3 0cm 只剩下10cm。使用下列關係計算損耗係數：損耗係數 =(-loglO(Ix/I〇))/(光程長度X)，其中Ix是每次切除連續的5cm 部分後通過積分球測得的強度，1〇是在樣品只剩下l〇cm時 5 通過積分球測得的強度，並且X是在每一次測量時的總長 度。對於未貼合和貼合的樣品中的任何一個，總光損耗測 量重覆兩次。在未貼合和貼合的樣品中測量的損耗基本上 相等，從而表明沒有由於將ESR膜貼合到聚碳酸酯導光板上 而引起的顯著的光損耗。Acting optical film combination 240. The optical film assembly 240 can include a pair of intersecting BEF prism films 244 with the prism faces of the prism film 244 facing the LCD module 260. As shown, the optical film assembly can also include an optional diffuser 242 and an optional DBEF reflective polarizer 246 that are placed on either side of the intersecting BEF prism 20 film 244. An optional diffuser 242 can be placed between the intersecting BEF prism film 244 and the backlight 220. In some cases, an optional optical film assembly 240 having a photo-loop effect may additionally include other membranes for further adjusting the light, such as diffusers, filters, and the like. A portion of the exiting light 230 entering the optical film assembly 240 having the optical loop effect is capable of transmitting the optical film combination in a direction toward the LCD 16 200916904 module 260. Another portion of the exiting light 230 entering the optical film assembly 240 is returned as re-circular light 235 through the front surface 222 to the backlight 220. As described elsewhere, the loop light 235 enters the front surface 222 of the conformal light guide plate 210 and propagates through the light guide plate 212 having a thickness greater than the diffraction 5 condition. The recirculating light 235 is finally reflected again by the reflective sheet 216 to the forward surface 222. Several different types of adhesive layers 214 having a thickness greater than the diffraction conditions may be used, such as a dry film hot melt adhesive, a dry film pressure sensitive adhesive 'radiation curable adhesive or a solvent based adhesive assembly to fit the light guide plate 21 Hey. The refractive index of the adhesive layer 214 having a thickness greater than 10 in the diffraction condition is smaller than the refractive index of the light guide plate 212. In some cases, the difference in refractive index is greater than 〇 〇〇 5, such as greater than 〇 〇 1, 0.1, 0.2 or more. The adhesive may form a continuous or discontinuous layer between the light guide plate 212 and the reflective sheet 216. In some cases, a continuous layer of adhesive 15 20 214 having a thickness greater than the diffraction conditions can ensure uniformity of the display and improve the performance of the backlight. For the detailed description, "continuous layer" means that the layer substantially covers the entire space between the light guide plate 212 and the reflection sheet 216 having a thickness larger than the diffraction condition, and the thickness of the sheet is larger than the diffraction condition. At least some portion of the space between the light guide plate 212 and the reflective sheet 216 is not covered by the layer. In some cases, the adhesive 214 having a thickness greater than the diffraction condition may be discontinuous, for example, by depositing a discontinuous adhesive pattern on the light guide plate 212 or the reflection sheet 216 having a thickness larger than the diffraction condition. In some cases, a uniform pattern of discontinuous adhesives may be used, such as uniformly distributing a plurality of adhesive portions of the light guide plate 1. In some cases, the discontinuous coating is discontinuous in the range of much smaller than the 17 200916904 light guide plate size, and the pattern of the adhesive layer is invisible when the light guide plate is used. Figure 2 shows the optical path of light propagating in the conformal light guide plate 21A. The light source 218, as shown by L 〇 in Fig. 2, projects light at a plurality of angles into the side 211 of the light guide plate 212 having a thickness greater than 5 diffraction conditions. The side 211 of the light guide plate 212 having a thickness larger than the diffraction condition forms an interface with the air having a refractive index n = 1. The light ray L 射 incident into the light guide plate 212 starts to propagate in the light guide plate 212 at an angle smaller than the critical angle ecg of the normal line of the side 211. For the sake of simplicity, only those rays propagating through the interface 213 between the light guide plate 212 having a thickness greater than the diffraction condition and the 10 adhesive 214 having a thickness greater than the diffraction condition will be discussed below, and the light is rayed in FIG. L is displayed. However, it should be understood that the incident light may also propagate toward the front surface 222 of the light guide plate 212. The front surface 222 is totally totally reflected, and continues in the light guide plate 212 at an angle smaller than the critical angle ecg of the normal of the side edge 211. propagation. 15 As shown in Fig. 2, some of the ray L, such as light, is reflected back into the light guide plate 212 by TIR. Some of the light L, such as light 12, is refracted into the adhesive, layer 214. The critical angle of the interface 213 is obtained by 0cga = arcsin (nadh / ng), and the refractive index of the light guide plate 212 is greater than the refractive index of the adhesive layer 214. The light L intersects the interface 213 at an angle greater than ecga and is therefore reflected back into the light guide plate 212 having a thickness greater than 20 diffraction conditions. The ray 12 intersects the interface 213 at an angle less than 0 cga' and is thus refracted into the adhesive 214 having a thickness greater than the diffraction condition. In the case where the front surface 222 is an air interface, the light ray h propagates at an angle greater than the critical angle of the two interfaces in the light guide plate 212 having a thickness greater than the incident condition, thus experiencing a full reflex in the light guide plate 212 having a thickness greater than the diffraction condition. 18 200916904 Shoot. In some cases, the light incident on the interface, such as the front surface 222, at or near the interface is associated with a light-emitting microstructure (not shown in Figure 2), resulting in at least a portion of the light from the light guide plate. The outgoing light 230 is shaped as a shape 5 . The microstructure that can cause the light to exit can be any of the extraction features that are not disclosed in this specification. For example, the microstructures can be located on the front surface 222, the interface 213, the interior of the light guide plate 212, or a combination thereof. The light may be reflected hundreds of times in the light guide plate 212 having a thickness greater than the diffraction condition. Thus, the portion of the light L incident into the light guide plate refracting 10 into the adhesive layer 214 at the time of the first intersection (丨2) may be a small portion of the total light propagating within the light guide plate. Light ray refracted into the adhesive layer 214 propagates through the adhesive layer 214 to the reflective sheet 216 and is reflected by the reflective sheet toward the front surface 222. If the relative refractive index of each layer follows the general relationship: (the refractive index of the light guide plate 212 15) 2 (the lowest refractive index in the reflective sheet 216) ^ (the refractive index of the adhesive layer 214), the light ray l2 can be reflected Sheet 216 is reflected. In the event that the inequality is not satisfied, a portion of the ray 12 can be transmitted through the reflective sheet 216, particularly as it circumscribes the non-air media around the reflective sheet 216. Similar to the manner in which the light ray L 〇 enters the edge 211, the loop light 235 enters the front surface 222 of the light guide plate 212 at an additional 20 angles. The front surface 222 of the light guide plate 212 also forms an interface with air, so that light propagates within the light guide plate 212 within the critical angle ecg of the normal of the front surface 222. A portion of the recirculating light 235 can undergo TIR at interface 213 and another portion can be refracted into the adhesive layer 214 in the manner described for ray L. However, because ecg <ecga, most of the 19 200916904 will be refracted into the adhesive layer 214 having a thickness greater than the diffraction condition and then reflected by the reflective sheet to the front surface 222. Exemplary embodiments will now be described in the following illustrative examples in which all parts and percentages 5 are by weight unless otherwise indicated. EXAMPLES Example 1: Optical loss from polycarbonate light guides with and without lamination 10 Using ~3 mil (.075 mm) thick optical adhesive (Opt-1 dust binder, also known as Bonding Systems) Division 9483 adhesive available from 3M Company), 20 mil (0.51 mm) thick film-type polycarbonic acid vinegar light guide (LEXAN® polycarbonate film 8010, available from GE Polymershapes, Seattle WA) Vikuiti ESRTM film (available from 3M 15 Company). The refractive index of the polycarbonate S-guide plate was 1.586, and the refractive index of the optical binder was 1.47. The laminate was applied at room temperature at 1.5 inches per minute (0.76 cm/sec) using a benchtop laminator (Catena 35, available from General Binding Corporation, Northbrook IL). The bonded sample and the unattached film type polycarbonate light guide plate were then cut into samples of about 6 cm 20 width and 30 cm length for testing. The total light loss (due to leakage, absorption, and scattering) of the bonded and unbonded samples was determined using a light source and an integrating sphere. A beam expander is used to spread the 543 nm laser, which is then converted into a parallel beam by a facet lens and then focused on the edge of the light guide. The light passing through the 3 cm long light guide plate and emitted from the far side of the 25 is captured by the integrating sphere. The light is measured using a photodetector attached to the integrating sphere 20 200916904 Intensity. The membrane was then cut 5 cm and the process was repeated until only 10 cm remained in the original 30 cm. The loss factor is calculated using the following relationship: loss factor = (-loglO(Ix/I〇)) / (path length X), where Ix is the intensity measured by the integrating sphere after each successive 5 cm portion is removed, 1〇 The intensity measured by the integrating sphere when the sample is only l〇cm, and X is the total length at each measurement. For any of the unattached and conformed samples, the total optical loss measurement was repeated twice. The losses measured in the unattached and conformed samples were substantially equal, indicating no significant optical loss due to the bonding of the ESR film to the polycarbonate light guide.
10 然後重復上述總光損耗實驗，不同之處在於使用LED 光源代替雷射。LED光源由從Nokia 7270行動電話（可獲自 Nokia Group，Finland)中取出的四個LED組成。LED在裝置 中並排排列並且相互間隔幾毫米。以13.7V和20mA的條件 驅動LED光源。總光損耗測量表明沒有由於將ESR膜層壓到 15 聚碳酸酯導光板上而引起的顯著的光損耗。 實施例2:貼有ESR膜的聚碳酸酯導光板的透射光譜 使用可獲自Perkin/Elmer的Lambda 900分光光度計’在 不同的入射角測量貼有ESR膜的聚碳酸酯導光板的透射光 2〇 譜。該實施例證明將ESR膜層壓到聚碳酸酯導光板上不會引 起ESR膜反射率的顯著降低。入射到每一個樣品中的光由與 ESR膜相對的聚碳酸酯薄板的表面進入。在400nm至700nm 的可見光譜區中測量每一個樣品的透射率。實施例1的貼合 樣品在0、15、30、45、60、和75°入射角下的光譜示於圖3 25 中。實施例1的未貼合樣品，ESR膜懸置於樣品底面（即，沒 21 200916904 有貼合，而是代之以空氣間隙），在0、15、30、45 ' 60和 75°入射角下的光譜示於圖4中。在大入射角下，透射光譜 朝藍-綠光譜一側略微偏移，但是貼合後的ESR膜的反射率 沒有顯著降低。 5 實施例3:使用貼合到聚碳酸酯導光板上的ESR的背光系 統的亮度和均勻性 利用厚聚碳酸醋膜（Panlite 115 1，可獲自Teijin Kasei， Alpharetta GA)加工成兩個15mil(381微米）厚的導光板。兩 10 個導光板在一個表面上具有相同的微結構（extractor)，以使 光能夠從導光板上的3 2 mm X 40 mm區域中出射。根據在實 施例1中描述的方法，使用厚度大於衍射條件的OPT-1黏合 劑將ESR膜在與微結構相對的一側貼合到其中一個導光板 上。 15 將每一個導光板放置於鋁外殼中，所述鋁外殼具有沿 著導光板的一個邊緣的第一開口，用於接受來自光源的 光，並且在導光板微結構一側所朝向的方向上具有約32 mm 寬和40mm長的第二開口。光源是在實施例1中描述的4個側 發光LED，所述LED的工作條件是13.7V和20 mA，與第一 20 開口對齊。導光板被在鋁外殼内側邊固定。 在鋁框架中的第二開口上覆蓋三張光學薄膜：一個散 射片（散射型聚碳酸酉旨，可獲自GE Polymershapes，Seattle WA)和兩個相交的棱鏡膜（TBEF和BEF-II，均可獲自3M Company)。沒有與ESR膜貼合的導光板在其下方放置一張 25 可以自由浮動的ESR膜。 22 200916904 用於測量光度的成像系統（PM-1600，可獲自Radiant Imaging Inc” Duvall WA)安置於第二開口上方，測量導光 板的空間亮度分佈。使用點測型亮度計（PR_65〇，可獲自10 Then repeat the above total optical loss experiment, except that the LED light source is used instead of the laser. The LED light source consists of four LEDs taken from the Nokia 7270 mobile phone (available from Nokia Group, Finland). The LEDs are arranged side by side in the device and are spaced apart from each other by a few millimeters. The LED light source is driven at 13.7V and 20mA. The total optical loss measurement showed no significant optical loss due to lamination of the ESR film onto the 15 polycarbonate light guide. Example 2: Transmission Spectrum of Polycarbonate Light Guide Plates with ESR Films The transmitted light of a polycarbonate light guide plate with an ESR film was measured at different incident angles using a Lambda 900 spectrophotometer available from Perkin/Elmer. 2 〇 spectrum. This example demonstrates that laminating an ESR film onto a polycarbonate light guide does not cause a significant reduction in the reflectance of the ESR film. Light incident into each sample enters the surface of the polycarbonate sheet opposite the ESR film. The transmittance of each sample was measured in the visible spectrum region of 400 nm to 700 nm. The spectrum of the bonded sample of Example 1 at 0, 15, 30, 45, 60, and 75° incident angles is shown in Figure 3 25. For the unattached sample of Example 1, the ESR film was suspended from the bottom surface of the sample (ie, no 21 200916904 fits, but instead air gap), at 0, 15, 30, 45 '60 and 75° angle of incidence The lower spectrum is shown in Figure 4. At large angles of incidence, the transmission spectrum shifted slightly toward the blue-green spectrum side, but the reflectance of the bonded ESR film did not decrease significantly. 5 Example 3: Brightness and uniformity of a backlight system using ESR bonded to a polycarbonate light guide plate. A thick polycarbonate film (Panlite 115 1, available from Teijin Kasei, Alpharetta GA) was processed into two 15 mils. (381 microns) thick light guide. The two 10 light guide plates have the same extractor on one surface to enable light to exit from the 3 2 mm X 40 mm area on the light guide plate. According to the method described in Example 1, the ESR film was attached to one of the light guide plates on the side opposite to the microstructure using an OPT-1 adhesive having a thickness larger than the diffraction condition. 15 placing each of the light guide plates in an aluminum housing having a first opening along one edge of the light guide plate for receiving light from the light source and in a direction in which the light guide plate microstructure side faces There is a second opening that is about 32 mm wide and 40 mm long. The light source is the four side-emitting LEDs described in Example 1, which operate at 13.7V and 20 mA, aligned with the first 20 opening. The light guide plate is fixed on the inner side of the aluminum casing. The second opening in the aluminum frame is covered with three optical films: a diffuser (scattered polycarbonate, available from GE Polymershapes, Seattle WA) and two intersecting prism films (TBEF and BEF-II, both Available from 3M Company). A light guide plate that is not attached to the ESR film is placed underneath a 25-degree free floating ESR film. 22 200916904 The imaging system for measuring luminosity (PM-1600, available from Radiant Imaging Inc. Duvall WA) is placed above the second opening to measure the spatial brightness distribution of the light guide. Using a spot-type luminance meter (PR_65〇, Obtained from
Photo Research Inc.，Chatsworth CA)校準亮度。 將這些導光板的凴度和均勻性相互比較。貼合esr膜 的導光板的亮度和均勻性比具有未貼合的樣品分別大23% 和 14% » 除非另外說明，否則應該認爲在本說明書和專利範圍 中所用的表示特徵尺寸、量和物理性能的所有數位是被詞 10 15 20 “約”所修飾的。因此’除非有相反說明，否則在上述說明 和後附申請專利範圍令提到的數字參數都是近似值，可以 根據使用在此公開的教導的本領域技術人M所尋求獲得的 需要的性能而改變。 除可能與本發明内容直接抵觸的内容以外，在此引用 的所有參考文獻和出版物的全部内容在此均通過引用清楚 地結合到本發明内容中。儘管在此舉例並且描述了且體實 施方案，但是本領域技術人員應該理解，在不偏離本發明 内容的範圍的情況下，多種替換和/或等同的實施方案可以 代替所顯神描述的具时施方案。本巾請意在覆蓋在此 論述的具體實施方㈣任何修改錢化。因此，意圖是本 發明只受到申請專利範圍及其等價物的限制。 圖式簡單說明】 圖1疋背光照明的顯示器的示意性横截面圓 23 200916904 圖2是顯示在導光板中的光線的傳播路徑的示意圖。 圖3是顯示導光板的透射率光譜圖。 圖4是顯示另一種導光板的透射率光譜圖。 5 【主要元件符號說明】 顯示器200 導光板212 反射片216 前表面222 光學膜組合240 反射式偏振片246 光線L〇, L，li，丄2 貼合型導光板21〇 介面213 光源218 出射光230 散射片242 背光模組250 臨界角0cg，0cga 側邊211 黏合劑層214 背光220 再迴圈光235 BEF棱鏡膜244 LCD模組260 折射率ng, nadh 24Photo Research Inc., Chatsworth CA) Calibrate the brightness. The twist and uniformity of these light guide plates are compared with each other. The brightness and uniformity of the light guide plate affixed to the esr film is 23% and 14% greater than that of the unattached sample, respectively. Unless otherwise stated, the size, amount and amount of features used in this specification and patent range should be considered. All digits of physical properties are modified by the word 10 15 20 "约". Accordingly, unless otherwise indicated, the numerical parameters recited in the above description and the appended claims are intended to be in an approximation, and may vary depending upon the desired performance sought by those skilled in the art using the teachings disclosed herein. . The entire contents of all of the references and publications cited herein are hereby expressly incorporated by reference in their entirety in their entirety in their entireties in the entire disclosure. While the embodiments are described and illustrated herein, it will be understood by those skilled in the art that various alternative and/or equivalent embodiments may be substituted for the presently described embodiments without departing from the scope of the invention. Scheme. This towel is intended to cover the specific implementation of this discussion (4) any modification of the money. Therefore, it is intended that the invention be limited only by the scope of the claims BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic cross-sectional circle of a backlight-illuminated display. 23 200916904 FIG. 2 is a schematic view showing a propagation path of light rays in a light guide plate. Fig. 3 is a view showing a transmittance spectrum of a light guide plate. Fig. 4 is a graph showing the transmittance spectrum of another light guide plate. 5 [Description of main component symbols] Display 200 Light guide plate 212 Reflector 216 Front surface 222 Optical film combination 240 Reflective polarizer 246 Light L〇, L, li, 丄2 Alignment type light guide plate 21 〇 Interface 213 Light source 218 230 diffuser 242 backlight module 250 critical angle 0cg, 0cga side 211 adhesive layer 214 backlight 220 recircular light 235 BEF prism film 244 LCD module 260 refractive index ng, nadh 24