201037415 六、發明說明： 【發明所屬之技術領域】 本發明是有關於一種液晶顯示器之背光模組， 是有關;^ __ π〜 '〜種提供極化光源的液晶顯示器之背光模組。 【先前技術】 面液曰9顯示器（liquid crystal display ; LCD)中的液晶顯示 ❹ 、、本身為非自發光顯示元件，需藉由背光模組提供所需 的光源並利用偏光板(Polarizer)將光源產生的光轉換成偏 ，光，以供液晶顯示器利用。由於背光模組與偏光板的性 倉b優劣會直接影響到液晶顯示器的品質，因此背光模組與 偏光板疋液晶顯示模組中的關鍵零組件。 一般而言，背光模組可概分為直下光源式(direct light tyPe)及侧向光源式(edge light type)二種形式。傳統上，背 光模組之光源係使用冷陰極管（CCFL)之類之燈管。然而， Q ^陰極T之色彩飽和度並不佳，無法呈現晝面之真實色 形。為達到較佳之色彩飽和度，近年來背光模組之光源係 傾向使用發光二極體(Light Emitting Diode ; LED)取代冷陰 極f。由於發光二極體具有體積小、壽命長、低驅動電壓、 耗電量低、耐震性佳、環保等優點，既可提供比冷陰極螢 光燈更豐富的色階，又可降低顯示器厚度，基於諸多優勢， 發光二極體儼然成為背光源中後起之秀。 . 偏光板通常設於液晶顯示面板的入光處和出光處，其 中位於背光模組光源和液晶顯示面板之間的偏光板，稱之 為‘下偏光板(polarizer)” ，用以將光源產生的光轉換成偏 3 201037415 極光，以供液晶顯示面板利用。而位於液晶顯示面板上相 對於下偏光板之一側的偏光板稱之為“上偏光板(analyzer or polarizer)” ，用以決定液晶顯示面板出光的極化方向和 大小。傳統上，上偏光板和下偏光板係統稱為偏光板，可 由一個以上的光學薄板所組成，除了原本的偏光功能外， 可更兼具例如防窺、光學補償等其他功能。 然而’習知偏光（膜）板所產生的極化光頻譜並不一 致，縱使利用其他方式改善，舉凡加入DBEF之類的偏光 〇 或增亮膜材，均會因為偏光(膜）板吸收光源能量而大幅影 響出光效率。此外，偏光板之設置亦造成液晶顯示器朝薄 型化發展上的侷限。 【發明内容】 因此，本發明之一態樣是在提供一種背光模組，其係 藉由k供極化光源直接提供偏振光，不僅毋需使用習知之 偏光(膜)板，更可提升光源之發光效率並純化出光頻譜。 ❹ 本發明另一態樣則是在提供一種液晶顯示器，其係藉 由提供具有極化光源之背光模組，不僅省略習知之下偏光 (膜）板，所提供頻譜純化之偏振光更提升液晶顯示器之色 彩表現。 根據本發明之上述態樣，提出一種背光模組，在無需 使用偏光（膜）板之情形下可直接提供偏振光並提升發光效 率。在一實施例中，此背光模組包含極化光源、面下式稜 ， 鏡片及擴散片。極化光源之出光面設有光子晶體層，使極 化光源產生之入射光轉變為具有第一偏振(p〇larized)態之 4 201037415 極化光。面下式稜鏡片設於極化光源之上方。擴散片設於 ' 面下式稜鏡片之上方。 根據本發明一實施例，上述光子晶體層包括複數層之 二維周期性晶格，每一層二維周期性晶格至少包含第一晶 格結構及第二晶格結構，其中第一晶格結構與第二晶格結 構為立體結構且以上下前後左右交替設置。經由第一晶格 結構與第二晶格結構的排列配置，可以僅讓具有第一偏振 態之入射光通過，並阻隔具有第二偏振態之入射光。在一 實施例中，第一偏振態可為橫向電場(transverse electric; Ο ΤΕ)偏振態’而第二偏振態可為橫向磁場（transverse magnetic ; TM)偏振態。 在本發明另一實施例中，上述背光模組可為直下式背 光模組或側光式背光模組。當上述背光模組為側光式背光 模組時’極化光源之出光處更可設有導光板，其中導光板 上可設有複數個V型（v-cut)微溝槽。 根據本發明之其他態樣’另提出一種液晶顯示器，藉 由提供具有極化光源之背光模組，可省略習知之下偏光(膜) ® 板，且所提供頻譜純化之偏振光進而提升液晶顯示器之色 彩表現。在一實施例中’此液晶顯示器包含背光模組及設 於背光模組上方之液晶層。此背光模組包含極化光源、面 下式稜鏡片及擴散片。極化光源之出光面設有光子晶體 層，使極化光源產生之入射光轉變為具有第一偏振態之極 化光。面下式稜鏡片設於極化光源之上方’擴散片設於面 . 下式稜鏡片之上方，而液晶層則設於該擴散片之上方，其 中液晶層的上方設置一上偏光(膜）板。 201037415 由上述可知，應用本發明之背光模組及其液晶顯： 器，其具有極化光源之背光模組，能於光源之出光面上= 由β史§十光子晶體層以直接提供偏振光，故毋需使用習知之 下偏光(膜）板，故可解決因習知之下偏光（膜）板吸收光溽能 量的問題，並可達成提升光源之發光效率、純化出光頻譜、 提升液晶顯示器之色彩表現的功效，進而提供薄型化液晶 顯示器。 θ9 0 【實施方式】 承前所述，本發明提供具有極化光源的液晶顯示器之 背光模組，藉由於光源之出光面上設計光子晶體層以直接 提供偏振光。當應用具有極化光源的背光模組及其液晶顯 示器時，可毋需使用習知之下偏光（膜）板，故可解決因習 知之下偏光（膜）板吸收光源能量的問題，並可達成提升光 源之發光效率、純化出光頻譜、提升液晶顯示器之色彩表 現的功效，進而提供薄型化液晶顯示器。以下藉由數個實 Q 施例說明本發明的細節。 請參照第1圖，其繪示依照本發明一實施例的一種用 於液晶顯示器之背光模組的結構分解圖。大體而言，此液 晶顯示器10包含背光模組100及設於背光模組100上方之 液晶層200。此背光模組100包含極化光源110、反射板 105、面下式稜鏡片170及擴散片180，其中面下式稜鏡片 170之下方可設有複數個V型（v-cut)微溝槽。依照本發明 •一實施例，面下式稜鏡片170可設於極化光源11〇之上方， - 擴散片180設於面下式稜鏡片170之上方，而液晶層200 201037415 則没於擴散片180之上方，其中液晶層200的上方可設置 一上偏光板220 ’且此上偏光板220可具有例如吸收軸225。 在本發明一實施例中，上述背光模組可為直下式背光 模組’然而在其他實施例中，上述背光模組亦可為侧光式 背光模組’如第1圖所示。當上述背光模組為側光式背光 模組時，極化光源110之出光處更可選擇性設有導光板 210，其中導光板210之下方亦可設有複數個v型微溝槽。 請參照第2圖，其繪示依照本發明另一實施例的一種 0 極化光源的立體示意圖。在此實施例中，極化光源110可 例如為發光二極體’其結構可包括但不限於在基材112上 堆疊緩衝層113、第一電性半導體層114及至少一層之主動 層12卜其中主動層121可例如為習知的多重量子井結構， 並覆蓋部分之第一電性半導體層114。主動層121上更可 堆疊第二電性半導體層122、透明導電層123、光子晶體層 124及第一電極127’其中透明導電層123可例如為銦錫氧 化物(ITO)’而第二電性半導體層122與第一電性半導體層 ❹ 114則具有相反之電性。第一電性半導體層114、主動層121201037415 VI. Description of the Invention: [Technical Field] The present invention relates to a backlight module for a liquid crystal display, relating to a backlight module of a liquid crystal display that provides a polarized light source. [Prior Art] The liquid crystal display in the liquid crystal display (LCD) ❹, itself is a non-self-luminous display element, which needs to provide the required light source by the backlight module and uses a polarizer (Polarizer) The light generated by the light source is converted into partial light and light for use by the liquid crystal display. Since the advantages and disadvantages of the backlight module and the polarizer of the polarizing plate directly affect the quality of the liquid crystal display, the backlight module and the polarizing plate are key components in the liquid crystal display module. In general, the backlight module can be divided into two types: a direct light tyPe and an edge light type. Traditionally, the light source of the backlight module uses a lamp such as a cold cathode tube (CCFL). However, the color saturation of the Q ^ cathode T is not good enough to present the true color of the face. In order to achieve better color saturation, in recent years, the light source of the backlight module has tended to use a Light Emitting Diode (LED) instead of the cold cathode f. Since the light-emitting diode has the advantages of small volume, long life, low driving voltage, low power consumption, good shock resistance, environmental protection, etc., it can provide a richer color gradation than the cold cathode fluorescent lamp, and can reduce the thickness of the display. Based on many advantages, the light-emitting diode has become a rising star in the backlight. The polarizing plate is usually disposed at the light entrance and the light exiting portion of the liquid crystal display panel, wherein the polarizing plate between the backlight module light source and the liquid crystal display panel is called a 'lower polarizer' for generating the light source. The light is converted into a polarized light of 201037415 for use by the liquid crystal display panel, and the polarizing plate located on one side of the liquid crystal display panel relative to the lower polarizing plate is called an "analyzer or polarizer" for determining The polarization direction and size of the light emitted by the liquid crystal display panel. Traditionally, the upper polarizing plate and the lower polarizing plate system are called polarizing plates, and may be composed of more than one optical thin plate, and in addition to the original polarizing function, Other functions such as optical compensation. However, the spectrum of polarized light generated by the conventional polarized film (film) is inconsistent. Even if it is improved by other means, polarized or brightened film such as DBEF will be polarized. The (film) plate absorbs the energy of the light source and greatly affects the light-emitting efficiency. In addition, the arrangement of the polarizing plate also causes the development of the liquid crystal display to be thinner. Therefore, an aspect of the present invention provides a backlight module that directly supplies polarized light by a polarized light source, which not only requires the use of a conventional polarizing (film) plate, but also enhances the light source. Luminous efficiency and purification of the optical spectrum. 另一 Another aspect of the present invention provides a liquid crystal display by providing a backlight module having a polarized light source, not only omitting a conventional polarized (film) plate, but also providing a spectrum. The purified polarized light further enhances the color performance of the liquid crystal display. According to the above aspect of the invention, a backlight module is provided, which can directly provide polarized light and improve luminous efficiency without using a polarizing (film) plate. In an example, the backlight module comprises a polarized light source, a sub-surface edge, a lens and a diffusion sheet. The light-emitting surface of the polarized light source is provided with a photonic crystal layer, so that the incident light generated by the polarized light source is converted into the first polarization (p 〇 larized state 4 201037415 polarized light. The subsurface cymbal is placed above the polarized light source. The diffuser is placed above the subsurface cymbal. According to an embodiment of the invention The photonic crystal layer includes a two-dimensional periodic lattice of a plurality of layers, each of the two-dimensional periodic lattices including at least a first lattice structure and a second lattice structure, wherein the first lattice structure and the second lattice structure It is a three-dimensional structure and is arranged alternately above and below, and the arrangement of the first lattice structure and the second lattice structure allows only incident light having a first polarization state to pass, and blocks incident light having a second polarization state. In an embodiment, the first polarization state may be a transverse electric field (transverse electric; Ο ΤΕ) polarization state and the second polarization state may be a transverse magnetic field (TM) polarization state. The backlight module may be a direct backlight module or an edge backlight module. When the backlight module is an edge-lit backlight module, the light-emitting source of the polarized light source may further be provided with a light guide plate, wherein the light guide plate may be provided with a plurality of V-cut micro-grooves. According to another aspect of the present invention, a liquid crystal display can be omitted. By providing a backlight module having a polarized light source, the polarized light (film) ® plate can be omitted, and the spectrally purified polarized light is provided to enhance the liquid crystal display. The color performance. In an embodiment, the liquid crystal display comprises a backlight module and a liquid crystal layer disposed above the backlight module. The backlight module comprises a polarized light source, a sub-surface cymbal and a diffusion sheet. The light-emitting surface of the polarized light source is provided with a photonic crystal layer, so that the incident light generated by the polarized light source is converted into polarized light having a first polarization state. The subsurface type cymbal is disposed above the polarized light source. The diffusion sheet is disposed on the surface of the lower type cymbal, and the liquid crystal layer is disposed above the diffusion sheet, wherein an upper polarizing film (film) is disposed above the liquid crystal layer. board. 201037415 It can be seen from the above that the backlight module and the liquid crystal display device thereof have the backlight module with polarized light source, which can directly provide polarized light on the light exit surface of the light source. Therefore, it is necessary to use a polarizing (film) plate under conventional knowledge, so that the problem of absorbing the optical energy of the polarizing (film) plate can be solved, and the luminous efficiency of the light source can be improved, the optical spectrum can be purified, and the color of the liquid crystal display can be improved. The performance of the performance, in turn, provides a thinned liquid crystal display. Θ9 0 [Embodiment] As described above, the present invention provides a backlight module for a liquid crystal display having a polarized light source, by designing a photonic crystal layer on the light exit surface of the light source to directly provide polarized light. When a backlight module having a polarized light source and a liquid crystal display thereof are applied, it is not necessary to use a conventional polarizing (film) plate, so that the problem of absorbing the light source energy by the polarized (film) plate can be solved and the improvement can be achieved. The luminous efficiency of the light source, the purification of the optical spectrum, and the improvement of the color performance of the liquid crystal display, thereby providing a thinned liquid crystal display. The details of the invention are illustrated below by a number of actual Q examples. Referring to FIG. 1 , an exploded view of a backlight module for a liquid crystal display according to an embodiment of the invention is shown. In general, the liquid crystal display 10 includes a backlight module 100 and a liquid crystal layer 200 disposed above the backlight module 100. The backlight module 100 includes a polarized light source 110, a reflective plate 105, a subsurface crotch plate 170, and a diffusion sheet 180. The V-cut micro-groove can be disposed under the sub-surface crotch plate 170. . According to an embodiment of the invention, the face-down cymbal 170 may be disposed above the polarized light source 11 ,, the diffusion sheet 180 is disposed above the face-down cymbal 170, and the liquid crystal layer 200 201037415 is absent from the diffusion sheet. Above the 180, an upper polarizing plate 220' may be disposed above the liquid crystal layer 200 and the upper polarizing plate 220 may have, for example, an absorption axis 225. In one embodiment of the present invention, the backlight module may be a direct-lit backlight module. However, in other embodiments, the backlight module may also be an edge-lit backlight module as shown in FIG. When the backlight module is an edge-lit backlight module, the light-emitting plate 210 can be selectively provided with a light guide plate 210. The plurality of v-shaped micro-grooves can also be disposed under the light guide plate 210. Please refer to FIG. 2, which is a perspective view of a 0-polarized light source according to another embodiment of the invention. In this embodiment, the polarized light source 110 can be, for example, a light emitting diode. The structure thereof can include, but is not limited to, stacking the buffer layer 113, the first electrical semiconductor layer 114, and at least one active layer 12 on the substrate 112. The active layer 121 can be, for example, a conventional multiple quantum well structure and covers a portion of the first electrical semiconductor layer 114. The second electrically conductive layer 122, the transparent conductive layer 123, the photonic crystal layer 124, and the first electrode 127' may be stacked on the active layer 121. The transparent conductive layer 123 may be, for example, indium tin oxide (ITO) and the second The semiconductor layer 122 and the first electrical semiconductor layer 114 have opposite electrical properties. First electrical semiconductor layer 114, active layer 121
以及第二電性半導體層122構成發光二極體之發光磊晶結 構。此外，未覆蓋主動層121之第一電性半導體層114的 部分上可堆疊包括但不限於鈍化層125及第二電極129。 在本發明的一個例子中，第一電性半導體層114可例如N 型半導體，第二電性半導體層12；2可例如P型半導體，第 一電極127可例如正極電極，而第二電極129可例如負極 .電極。然而在本發明另一個例子中，第一電性半導體層U4 亦可例如P塑半導體，第二電性半導體層122亦可例如N 7 201037415 型半導體’第—電極127亦可例如負極電極’而第二電極 129亦可例如正極電極。And the second electrical semiconductor layer 122 constitutes a light emitting epitaxial structure of the light emitting diode. Further, the portion of the first electrical semiconductor layer 114 that does not cover the active layer 121 may be stacked including, but not limited to, the passivation layer 125 and the second electrode 129. In one example of the present invention, the first electrical semiconductor layer 114 may be, for example, an N-type semiconductor, the second electrical semiconductor layer 12; 2 may be, for example, a P-type semiconductor, the first electrode 127 may be, for example, a positive electrode, and the second electrode 129 For example, a negative electrode. However, in another example of the present invention, the first electrical semiconductor layer U4 may also be, for example, a P-plastic semiconductor, and the second electrical semiconductor layer 122 may also be, for example, a N 7 201037415 type semiconductor 'electrode 127 may also be, for example, a negative electrode' The second electrode 129 can also be, for example, a positive electrode.
明再參照第2圖，極化光源11〇 一般係以透明導電層 123之上表面為出光面111，在此出光面111上設有光子晶 體層124，使極化光源n〇產生之入射光通過光子晶體層 124以產生具有第一偏振態而不包含第二偏振態之極化 光，藉以取代習知之下偏光（膜）板。申言之，此光子晶體 層124包括以間隔週期性排列之複數層二維周期性晶格， 其層數不拘。在—實施例中，光子晶體層124可包括例如 2層至15層之二維周期性晶格。在另一實施例中，光子晶 體層124可包括例如5層至9層之二維周期性晶格。 在光子晶體層12”，每一層二維周期性晶格至少包 含第一晶格結構13la及第二晶格結構133a。一般而古，第 -晶格結構ma與第二晶格結構133a之獨立向量^形成 之平面以垂直於上述發光遙晶結構的方向為宜。在本發明 的一個例子中，因為第一晶格結構131 =二f :率’進而省略習知之下偏光(膜)板的 ，用。上这之4 -偏振態可例如為橫向電麵咖 融1C;TE)偏振態’而第二偏振態可例如為橫向磁場 (tiansvetse magnetic ; TM)偏振態。 如第2圖之所示 W 本發明之極化光源110的第-電極 ”第一電極129雖分別位於光子晶體層m與鈍化芦 125之約中心處，然而本發明並不限於此。 曰 中’為獲致更佳的出光效率，第—電極127與第1電極129 8 201037415 亦可分別設於光子晶體層124與鈍化層125之近邊緣處、 或光子晶體層124與鈍化層125之其他位置（圖未緣示）。 ο 根據本發明一實施例，光子晶體層124之第一晶格結 構131a及第二晶格結構133a可進一步利用下列製程形 成。請參閱第3A圖至第3E圖，其係繪示依照本發明又一 實施例形成光子晶體層之不同製程階段之剖面示意圖。請 參閱第3A圖，首先，形成材料層131於光源11〇之出光面 U1上，例如透明導電層123之上表面，其中材料層131 之材質可包括但不限於矽、磊晶、二氧化矽、非晶矽或三 五族化合物。接著，進行一微影製程，其係利用紫外光UV 透過具有預設圖案之光罩14〇對材料層131曝光、顯影及 藉以形成-層周期性之第—晶格結構ma，其中第 Γ晶格結構13la係暴露出複數個開口 132,如第3B圖所 二。然後’將材料層133沉積於上述開口 132中，其中材 〇 可包括但不限於環氧樹脂或陽離子聚合樹 二二曰133經過平坦化製程後形成第二晶格結構 維周期i日i格結構l3ia與晶格結構i33a形成第一層二 構133a在曰曰同L1】1 ’意即第一晶格結構131a與第二晶袼結 °平面以前後左右交替設置，如第3C圖所示。 製程述第3A圖至第3C圖之微影製程及研磨 周期=格It圖，形成材料層131於第-層二維 之光罩$上，並利用紫外光UV透過具有預設圖案 九罩142對材料層131 料層133並平“ 竭⑥關/儿積材 153。以笛ip二匕後，形成至少二層之二維周期性晶格 圖為例，其中第二層二維周期性晶格153與 9 201037415 第-層二維周期性晶格⑸中之第—晶格結構13u盘第二 晶格結構咖係以上下前後左右交替設置，如第3e、圖所 不〇 曰大體而言’第-晶格結構l31a與第二晶格結構咖 之晶格常數(lattice constant)可介於1〇〇奈米至15〇奈米之 Ο ❹ 間，其係適用於將波長介於約380奈米至約72〇奈間 ^入射光，極化成激發光譜半寬度料、波長介^ 5〇Β〇 不米至約59〇奈米之間的極化光。第一晶格結構⑶&鱼第 了晶格結構man由間隔關性㈣，以提供_純化之 偏振光。誠如上述’第-晶格結構13la 但不限_、蟲晶、二氧切、非晶梦、三五族化= 2族化合物’第二晶格結構133a之材質一般可包括但不 限於環氧樹脂或陽離子聚合樹脂。 在本發明的一個例子中，第一晶格結構131&與 化=I%均為iL體結構’且二者以間隔週期性排列於極 〜之出光面上，藉此提供頻譜純化之偏振光。第一曰日 =構ma與第二晶格結構133a均為立體結構，一般包 ^不限於例如多角柱體(例如：三角柱體、立方柱體、長 桂體、五角柱體、六角柱體、七角柱體 ^種多角柱體)、圓柱體等各種立體== 。藉由第一晶格結構131a與第二晶 門 =性排列，上下前後左右交替之週期：= 匕先源之出光面上，可提供頻譜純化之偏振光。 ^參照第4圖’赌示依照本發明再—實施例的一種 日日體月b隙圖’其中橫轴代表波向量（wave彻㈣，縱轴 201037415 代表標準化頻率（normalized frequency ; a/λ)，而標準化頻 率係指晶格常數(lattice constant) a與入射光波長χ之比 例。以第4圖為例，第一晶格結構與第二晶格結構可例如 立方柱體結構，且彼此以上下前後左右交替之週期性設置 於極化光源之出光面。根據第4圖之結果，從波向量γ_μ 方向及從波向量Γ·χ方向可以得知，本發明極化光源之光 子晶體層其橫向磁場偏振態的光子能隙波段介於標準化頻 率（a/λ)約0.20至約0 27之範圍時，可有效阻隔橫向磁場偏 〇 振態之入射光通過，藉此提供頻譜純化之偏振光、提升發 光效率，進而省略習知偏光(膜)板之使用。 由前述說明可知’藉由挑選合適的晶格常數(a為晶格 常數）之材質形成第一晶格結構131a與第二晶格結構 133a ’並且搭配特定的入射光波長(λ)，可以得到特定的光 +能隙波段’藉以提供頻譜純化之偏振光。舉例而言，當 入射光波長為介於約38G奈米至約480奈米之間的藍光 時’可以適用晶格常數約1〇〇奈米之材質作為第一晶格結 〇構131a與第二晶袼結構133a。S其他例子中，f入射光波 長為介於約480奈米至約58〇奈米之間的綠光時，可以適 用，格常數❸120奈米之材質作為第-晶格結才冓131a與第 一的格、、、"構133a。或者，在其他例子中，當入射光波長為 ’I於約580奈米至約72q奈米之間的紅光時，可以適用晶 格本數、約150奈米之材質作為第一晶格結構131a與第二晶 格結構13 3 a。 、$本發明上述實施例可知，應用本發明之背光模組及 ’其具有極化光源之背光模組，能緩於光源 11 201037415 之出光面上藉由設計光子晶體層以直接提供偏振光，故毋 ' 需使用習知之下偏光（膜）板，故可解決因習知之下偏光（膜) 板吸收光源能量的問題，並可達成提升光源之發光效率、 純化出光頻譜、提升液晶顯示器之色彩表現的功效，進而 提供薄型化液晶顯示器。 雖然本發明已以數個實施例揭露如上，然其並非用以 限定本發明，在本發明所屬技術領域中任何具有通常知識 者，在不脫離本發明之精神和範圍内，當可作各種之更動 q 與潤飾，因此本發明之保護範圍當視後附之申請專利範圍 所界定者為準。 【圖式簡單說明】 為讓本發明之上述和其他目的、特徵、優點與實施例 能更明顯易懂，所附圖式之詳細說明如下： 第1圖係繪示依照本發明一實施例的一種用於液晶顯 示器之背光模組的結構分解圖； Ο 第2圖係繪示依照本發明另一實施例的一種極化光源 的立體示意圖； 第3A圖至第3E圖係繪示依照本發明又一實施例形成 光子晶體層之不同製程階段之剖面示意圖；以及 第4圖係繪示依照本發明再一實施例的一種光子晶體 能隙圖。 【主要元件符號說明】 100:背光模組 131a:第一晶格結構 12 201037415 105 :反射板 110 :極化光源 111 :出光面 112 :基材 113 :緩衝層 114 :第一電性半導體層 121 :主動層 122 :第二電性半導體層 123 :透明導電層 124 :光子晶體層 125 :鈍化層 127 :第一電極 129 :第二電極 131 :材料層 132 :開口 133 :材料層 133a :第二晶格結構 140/142 :光罩 151 :第一層二維周期性晶格 153 :第二層二維周期性晶格 160 :偏振光 170 :面下式稜鏡片 180 :擴散片 200 :液晶層 210 :導光板 UV :紫外光 220 :上偏光板 225 :吸收軸Referring to FIG. 2 again, the polarized light source 11A generally has a light-emitting surface 111 on the upper surface of the transparent conductive layer 123, and a photonic crystal layer 124 is disposed on the light-emitting surface 111 to make the incident light generated by the polarized light source n〇. The photonic crystal layer 124 is passed through to generate polarized light having a first polarization state and not including a second polarization state, thereby replacing the conventional polarized (film) plate. In other words, the photonic crystal layer 124 includes a plurality of layers of two-dimensional periodic lattices periodically arranged at intervals, the number of layers being independent. In an embodiment, photonic crystal layer 124 can comprise, for example, a two-dimensional periodic lattice of two to fifteen layers. In another embodiment, photonic crystal layer 124 can comprise, for example, a two-dimensional periodic lattice of five to nine layers. In the photonic crystal layer 12", each of the two-dimensional periodic lattices includes at least a first lattice structure 13la and a second lattice structure 133a. Generally, the first-lattice structure ma is independent of the second lattice structure 133a. The plane formed by the vector ^ is preferably perpendicular to the direction of the above-mentioned luminescent crystal structure. In one example of the present invention, since the first lattice structure 131 = two f: rate ', the conventional polarized (film) plate is omitted. The 4-polarization state can be, for example, a lateral electrical surface melting 1C; a TE) polarization state and a second polarization state can be, for example, a transverse magnetic field (tiansvetse magnetic; TM) polarization state. The first electrode 129 of the polarized light source 110 of the present invention is located at approximately the center of the photonic crystal layer m and the passivation reed 125, respectively, but the present invention is not limited thereto. In order to achieve better light extraction efficiency, the first electrode 127 and the first electrode 129 8 201037415 may also be disposed at the near edge of the photonic crystal layer 124 and the passivation layer 125, or the photonic crystal layer 124 and the passivation layer 125, respectively. Other locations (not shown). According to an embodiment of the invention, the first lattice structure 131a and the second lattice structure 133a of the photonic crystal layer 124 may be further formed by the following processes. Please refer to FIGS. 3A-3E, which are schematic cross-sectional views showing different process stages of forming a photonic crystal layer according to still another embodiment of the present invention. Referring to FIG. 3A, first, a material layer 131 is formed on the light-emitting surface U1 of the light source 11 , for example, the upper surface of the transparent conductive layer 123 . The material of the material layer 131 may include, but not limited to, germanium, epitaxial, and hafnium oxide. , amorphous or tri-five compounds. Next, a lithography process is performed, which exposes, develops, and forms a layer-periodic first-lattice structure ma by ultraviolet light UV through a photomask 14 having a predetermined pattern, wherein the first crystal The lattice structure 13la exposes a plurality of openings 132, as shown in Fig. 3B. Then, a material layer 133 is deposited in the opening 132, wherein the material may include, but is not limited to, an epoxy resin or a cationic polymeric tree 222. After the planarization process, a second lattice structure is formed. L3ia forms a first layer two structure 133a with the lattice structure i33a. In the same way, the first lattice structure 131a and the second crystal lattice junction plane are arranged alternately before and after, as shown in FIG. 3C. The lithography process and the polishing cycle of the 3A to 3C processes are shown in FIG. 3, and the material layer 131 is formed on the first-layer two-dimensional photomask $, and is irradiated with ultraviolet light UV through a preset pattern nine cover 142. For the material layer 131, the material layer 133 is flattened and exhausted. The two-dimensional periodic crystal lattice pattern of at least two layers is taken as an example, wherein the second layer of two-dimensional periodic crystals is taken as an example. Grids 153 and 9 201037415 The first layer of the two-dimensional periodic lattice (5) - the lattice structure of the 13u disk, the second lattice structure, the coffee system is alternately arranged above and below, as in the case of 3e, the figure is generally The lattice constant of the first-lattice structure l31a and the second lattice structure may range from 1 nanometer to 15 nanometers, which is suitable for wavelengths of about 380. From nanometer to about 72 〇, the incident light is polarized into a polarized light with an excitation spectrum half-width material and a wavelength ranging from 5 〇Β〇 not meters to about 59 〇 nanometer. The first lattice structure (3) & fish The first lattice structure man is separated by (4) to provide _purified polarized light. As described above, the 'first-lattice structure 13la is not limited to _, insect crystal, Oxygen cut, amorphous dream, tri-five grouping = Group 2 compound 'The material of the second lattice structure 133a may generally include, but is not limited to, an epoxy resin or a cationic polymer resin. In one example of the present invention, the first lattice Structure 131 & ==I% is iL body structure' and both are periodically arranged at intervals on the exit surface of the pole to provide spectrally purified polarized light. The first day = configuration ma and second crystal The lattice structure 133a is a three-dimensional structure, and the general package is not limited to, for example, a polygonal cylinder (for example, a triangular cylinder, a cubic cylinder, a long cinnamon, a pentagonal cylinder, a hexagonal cylinder, a seven-corner cylinder, a polygonal cylinder), and a cylinder. The body and other various stereoscopic ==. By the first lattice structure 131a and the second crystal gate = sexual arrangement, the period of up, down, front, left, and right alternating: = 匕 the source of the light surface, can provide spectrally purified polarized light. Figure 4 is a diagram showing a daily body-month b-slot diagram in accordance with a further embodiment of the present invention, wherein the horizontal axis represents a wave vector (wave (4) and the vertical axis 201037415 represents a normalized frequency (a/λ), and Normalized frequency refers to lattice constant (lattice cons The ratio of tant) a to the wavelength χ of the incident light. Taking FIG. 4 as an example, the first lattice structure and the second lattice structure may be, for example, a cubic cylinder structure, and the periodicity of each of the front, back, left, and right sides is alternately set to the polarization. According to the result of Fig. 4, it can be known from the wave vector γ_μ direction and from the wave vector Γ·χ direction that the photonic crystal layer of the polarized light source of the present invention has a photonic energy gap band of the transverse magnetic field polarization state. When the normalized frequency (a/λ) is in the range of about 0.20 to about 0 27, the incident light of the transverse magnetic field yaw state can be effectively blocked, thereby providing spectrally purified polarized light, improving luminous efficiency, and omitting conventional polarized light ( The use of membranes). It can be seen from the above description that the first lattice structure 131a and the second lattice structure 133a' are formed by selecting a material having a suitable lattice constant (a is a lattice constant) and matching a specific incident light wavelength (λ). The specific light + band gap ' is used to provide spectrally purified polarized light. For example, when the incident light wavelength is between about 38 G nm to about 480 nm, the material having a lattice constant of about 1 〇〇 nanometer can be applied as the first lattice junction structure 131a and the first The twin crystal structure 133a. In other examples, when the wavelength of incident light is between 480 nm and about 58 nm, it can be applied. The material with a lattice constant of 奈120 nm is used as the first-lattice 冓131a and the first A Grid,,, " Structure 133a. Alternatively, in other examples, when the incident light has a wavelength of 'I from about 580 nm to about 72 q nm, a material having a lattice number of about 150 nm can be applied as the first lattice structure. 131a and a second lattice structure 13 3 a. According to the above embodiment of the present invention, the backlight module of the present invention and the backlight module having the polarized light source can be used to directly provide the polarized light by designing the photonic crystal layer on the light exit surface of the light source 11 201037415. Therefore, it is necessary to use the polarized (film) plate under the conventional knowledge, so that the problem of absorbing the light source energy by the polarized (film) plate can be solved, and the luminous efficiency of the light source can be improved, the optical spectrum can be purified, and the color performance of the liquid crystal display can be improved. The effect, in turn, provides a thinned liquid crystal display. While the invention has been described above in terms of several embodiments, it is not intended to limit the scope of the invention, and the invention may be practiced in various embodiments without departing from the spirit and scope of the invention. The scope of protection of the present invention is defined by the scope of the appended claims. BRIEF DESCRIPTION OF THE DRAWINGS The above and other objects, features, advantages and embodiments of the present invention will become more <RTIgt; FIG. 2 is a perspective view showing a polarized light source according to another embodiment of the present invention; FIGS. 3A to 3E are diagrams showing the present invention A further cross-sectional view of a different process stage of forming a photonic crystal layer; and FIG. 4 is a photonic crystal energy gap diagram according to still another embodiment of the present invention. [Description of main component symbols] 100: backlight module 131a: first lattice structure 12 201037415 105: reflector 110: polarized light source 111: light-emitting surface 112: substrate 113: buffer layer 114: first electrical semiconductor layer 121 Active layer 122: second electrical semiconductor layer 123: transparent conductive layer 124: photonic crystal layer 125: passivation layer 127: first electrode 129: second electrode 131: material layer 132: opening 133: material layer 133a: second Lattice structure 140/142: photomask 151: first layer two-dimensional periodic lattice 153: second layer two-dimensional periodic lattice 160: polarized light 170: subsurface type wafer 180: diffusion sheet 200: liquid crystal layer 210: Light guide plate UV: Ultraviolet light 220: Upper polarizing plate 225: Absorption axis
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