41834 B7 五、發明說明（/ ) 習知技術之說明 應用於背面式(rear-type)影像系統之投影螢幕，通常被 用於觀看一物體投影至後表面並發散至前表面之影像。背 面式影像系統之實例包括：背面式投影大螢幕電視接收器 、背面式幻燈片投影機，以及背面式微影片閱讀機。 如圖1所示，在習知技術系統中，一具有單獨薄板之 Fresnel透鏡10被放置在一位於輸入面11之投影機制與影 像螢幕12之間。Fresnel透鏡之主要目的，係增強中心至 .邊緣亮度的均勻度。如熟習此項技藝者所知，Fresnel透鏡 10之Fresnel面(facets)會聚集入射光並平行射入影像螢幕 12。影像螢幕12包含一大型散光器(diffuseOM，其可將光 發散成特定的增益剖面。前表面層16通常係由丙烯酸 (acrylic)或玻璃所組成，其配置於影像螢幕12之觀看端 (viewing side)，以保護散光器14。 由於Fresnel透鏡之第二重內反射與折射的效應，如 上之配置將會在螢幕上產生「鬼影」（ghost images)。如此 之鬼影在高解析度系統中將更爲顯著。此現象將參閱圖2 ，以做更加詳盡的說明。出現在影像螢幕上的鬼影，係一 種正常影像之次要且較暗淡的影像。例如，當螢幕的背景 是黑暗的，且間隔很大的文字字體顯示在螢幕之角落時， 鬼影的現象將更爲明顯。吾人可見這些字體之次要的影像 或鬼影較爲暗淡，並且向螢幕中央偏移。 一光線通過A點，與Fresnel透鏡10之扁平的一面相 交於B點，並折射至C點。在C點，大部分的光係透過 3 紙張尺度適^中國國家標準(CNS)A4規格.(210 X 297公釐） (請先閲讀背面之注意事項再填寫本頁) ^--------訂---------.線- 經濟部智慧財產局員工消費合作社印製 4ί§341 μ __B7___ 五、發明說明（立）41834 B7 V. Description of the Invention (/) Description of Conventional Technology A projection screen applied to a rear-type imaging system is usually used to view an image of an object projected on the rear surface and divergent to the front surface. Examples of back-type imaging systems include: rear-projection large-screen TV receivers, rear-type slide projectors, and rear-type micro-film readers. As shown in FIG. 1, in the conventional technology system, a Fresnel lens 10 having a separate thin plate is placed between a projection mechanism located on the input surface 11 and an image screen 12. The main purpose of Fresnel lenses is to enhance the uniformity of brightness from the center to the edges. As known to those skilled in the art, the Fresnel facets of the Fresnel lens 10 collect incident light and enter the image screen 12 in parallel. The image screen 12 includes a large diffuser (diffuseOM), which can diffuse light into a specific gain profile. The front surface layer 16 is usually composed of acrylic or glass, and is arranged at the viewing side of the image screen 12 ) To protect the diffuser 14. Due to the second internal reflection and refraction effect of the Fresnel lens, the above configuration will produce "ghost images" on the screen. Such ghost images are used in high-resolution systems It will be more prominent. This phenomenon will be described in more detail with reference to Figure 2. The ghost image that appears on the image screen is a secondary and faint image of a normal image. For example, when the screen background is dark When the spaced text font is displayed at the corner of the screen, the ghost phenomenon will be more obvious. We can see that the secondary image or ghost image of these fonts is dim and shifts toward the center of the screen. A light passes through Point A intersects with the flat side of the Fresnel lens 10 at point B and is refracted to point C. At point C, most of the light is transmitted through 3 paper standards ^ China National Standard (CNS) A4 specifications. (210 X 297 mm) (Please read the precautions on the back before filling out this page) ^ -------- Order --------- .. Line-Printed by Employee Consumer Cooperatives of the Intellectual Property Bureau of the Ministry of Economic Affairs 4ί §341 μ __B7___ V. Explanation of the Invention (Li)
Fresnel面折射至D點，其在漫射螢幕(diffusion screen)上 形成吾人所需之主要影像。然而，在C點，有相當部分的 光自Fresnel面反射回來，並導回至Fresnel透鏡10之內部 的E點。由於在E點的入射角大於臨界角，光線中所有的 能量將藉由全內部反射(total internal reflection)反射回來。 而後，該光線通過Fresnel透鏡10之豎板表面（draft surface)18，並射出至F點。此次要的光線較爲暗淡’並且 在C點自主要光線偏移開來，其係形成鬼影的來源。 例如在運送過程中，習知技術的結構亦由於影像螢¥ 刮擦Fresnel透鏡所造成之有害效應而更形惡化。Fresnel 透鏡之刻面化（faceted)光學表面非常脆弱且輪廓鮮明。在 搬運過程中的震動將可能造成Fresnel透鏡摩擦螢幕’而損 害其一或兩者之零件。當透鏡與螢幕暴露於能導致表面白勺 損害之極端溫度及/或溼度的環境時，將造成變形扭曲成$ 均句態。 發明槪要 一種投影螢幕，其包含一具有第一面與第二面之散光 .器，以及一位於第一面之整合光學元件。一前表面層配置 於該散光器之第二面。在一實施例中，該前表面層係層壓 (laminated)於該散光器之第二面。 光學元件(optical element)可包括一 Fresnel透鏡、一 雙凸透鏡陣列（lenticular array)，以及複數個稜鏡或其相似 物，其可使照射光線準直或轉向。光線穿過光學元件與育女 光器更佳。The Fresnel surface is refracted to point D, which forms the main image we need on the diffusion screen. However, at point C, a considerable portion of the light is reflected back from the Fresnel surface and guided back to point E inside the Fresnel lens 10. Since the angle of incidence at point E is greater than the critical angle, all energy in the light will be reflected back by total internal reflection. The light then passes through the draft surface 18 of the Fresnel lens 10 and exits to point F. The main light this time is relatively dim 'and shifted away from the main light at point C, which is the source of ghost images. For example, during the transportation process, the structure of the conventional technology is further deteriorated due to the harmful effects caused by scratching the Fresnel lens. The faceted optical surface of Fresnel lenses is very fragile and well-defined. Vibration during handling may cause the Fresnel lens to rub the screen ’and damage one or both of its parts. When the lens and screen are exposed to extreme temperature and / or humidity conditions that can cause damage to the surface, distortion will result in distortion. The invention requires a projection screen, which comprises a diffuser having a first surface and a second surface, and an integrated optical element on the first surface. A front surface layer is disposed on the second side of the diffuser. In one embodiment, the front surface layer is laminated on the second side of the diffuser. The optical element may include a Fresnel lens, a lenticular array, and a plurality of chirps or the like, which can collimate or turn the irradiated light. It is better for light to pass through optics and childcare devices.
•V 本紙張尺度適用中國國家標準（CNS)A4規格（210 X 297公釐） (諳先閲讀背面之注意事項再填寫本頁) ^1 ^1 ί ·1 n n I n n n I i~ 經濟部智慧財產局員工消費合作社印製 418341 ___—_ B7 五、發明說明（$ ) 散光器包括一聚合承載基質（polymeric carrier substrate)以及散佈於整個承載基質之聚合小透鏡(lenslet)粒 子。該小透鏡粒子可爲球形、橢圓形，或其他會直接影響 增益剖面（gain profile)之幾何形狀。小透鏡粒子和承載基 質最好分別具有不同的折射率。在一實施例中，小透鏡粒 子的折射率約介於1.55至1.60之間，而承載基質的折射 率則小於約1.54。 前表面層可包含一抗反射塗層（anti-reflective coating) 或在其上之硬塗層(hardcoat)。前表面層亦可包含一表面粗 糖化（matte)或反亮光（anti-glare)加工處理。前表面層含有 中性密度色調(neutral density tint)，以增強對比。在另一 實施例中，前表面層包含一反射表面，其可使通過光學元 件與散光器之光線改變方向。此反射表面可包括線性或立 方體包角（cube-corner)之稜鏡。 本發明之投影螢幕可用於前面式或背面式影像投影系 統，且本發明之投影螢幕可大大地降低或消除Fresnel式鬼 影。此投影螢幕亦具有輕巧之優點，其與習知的系統比較 之下僅需較少的組裝步驟，因而其成本較低。 圖式簡單說明 藉由以下本發明之較佳實施例更加詳盡的說明’本發 明之前述與其他的目的、技術特徵以及各項優點將更加顯 而易見。如附加圖式所示，相同的參考符號係指各個不同 視角之同一零件。所附圖式不一定需要按照比例’而著重 於闡明本發明之原理。 5 本紙張尺度適用中國國家標準（CNS)A4規格（210 X 297公餐） <請先閲讀背面之注意事項再填寫本頁) i--------訂---------線. 經濟部智慧財產局員工消費合作社印製 416341 A7 B7 五、發明說明（Ψ ) (請先閱請背面之注意事項再填寫本頁) 圖1係用於背面式影像系統之習知影像螢幕的側視圖 圖2係圖1中區域的放大圖，用以圖解鬼影效應 9 圖3係依照本發明應用於背面式影像系統之影像螢幕 的側視圖； 圖4係圖3中區域”B"的放大圖； 圖5係一影像螢幕之等軸觀視(isometric view)圖，其 圖解用於測量，從影像螢幕而來之光輸出量的第一參考點； 圖6係一圖表，其圖解從一影像螢幕之中心所觀察到 的水平與垂直角度之增益分佈； 圖7係一影像螢幕之等軸觀視圖，其圖解用於測量從 影像營幕而來之光輸出量的第二參考點； 線- 圖8係一圖表，其圖解從一影像螢幕之外部邊緣所觀 察到的增益分佈。 經濟部智慧財產局員工消費合作社印製 元件符號說明 10 Fresnel 透鏡 11輸入面 12影像螢幕 14散光器 16前表面層 18豎板表面 20影像螢幕 22光學元件 ( 6 本紙張尺度適用_國國家標準（CNS)A4規格（2ΐα X 297公釐） 4 183 4 1 A7 B7 五、發明說明（夕） 24散光器 26表面層 ' 28輸入端 30觀看端 32背面式投影螢幕電視_ 34投影系統 36透鏡系統 38面鏡 40面鏡 較佳實施例之詳細說明 本發明之較佳實施例的詳細說明如下。圖3係圖解一 影像螢幕20之較佳實施例，其係用於如前面式與背面式投 影系統。影像螢幕20包括一光學元件22整體形成於散光 器24上，且該散光器最好層壓於前表面層26。光學元件 22可包含一 Fresnel透鏡、一雙凸透鏡陣列、稜鏡或其相 似物，該光學元件使照射光線平行行進或轉向。光線最好 能夠通過光學元件22以及散光器24。 位於影像螢幕20之輸入端2S的投影系統，在其上形 成一藉由光學元件22而得之準直影像。此準直影像係藉由 散光器24漫射一特定的增益剖面至一輸出端，即觀看端 30。含有丙烯酸、玻璃或其相似物之前表面層26可包含一 中性密度色調，以增強對比。前表面層26亦可包含一抗反 射塗層及/或一經過加工處理之硬塗層，且上述塗層最好位 於朝向觀看端30之最外層。前表面層26亦可包含一表面 7 本紙張尺度適用中國國家標準（CNS)A4規格（210 X 297公釐） <請先閲讀背面之注意事項再填寫本頁) ^--------訂---------線. 經濟部智慧財產局員工消費合作社印製 -I ί a— <1 n a— u n ί 418341 A7 B7 五、發明說明（έ ) 粗糖化或反売光加工處理。 在另一實施例中，前表面層26包含一反射表面，其可 使通過光學兀件22與散光器24之光線改變方向。在一_實 施例中，反射表面可包括線性稜鏡，如1974年11月5日 授予Brown之美國專利第3,846,012號，以及19W年4月 7日授予Whitehead之美國專利第4,260,220號所揭露者。 在此納入上述兩核准專利案所揭露者，係作爲參考。在另 一實施例中，反射表面包含立方體包角之稜鏡，如1973年 .1月23日授予Stamm之美國專利第3,712,706號、1972年 8月14日授予Rowland之美國專利第3,684,348號，以及 1972年9月5日授予Rowland之美國專利第3,689,346號 所揭露者。在此納入每一個核准專利案所揭露者，係作爲 參考。 圖4爲依照本發明在散光器24上所形成之光學元件 22的圖解。在此實施例中，該光學元件面朝向從投影系統 而來的入射光線，以使光線通過A點。通過A點之光線照 射至光學元件22上的B點，且透鏡將該光線折射至一平 行方向。而後該光線照射到散光器24上的C點；在此處 ，該光線以較廣之立體角發散至輸出空間D。光學元件22 的斜面部分，並不會產生任何鬼影。光學元件22之聱板 (draft or riser)部分的確會造成光線的損失與散射，但此散 射光係凌亂且不會形成任何第二重影像。 散光器24可由依照專利合作協定於1996年7月4臼 出版之國際出版編號第WO 96/20419號所揭露之材料來形 8 本紙張尺度適用中國國家標準（CNS)A4規格（210 x 297公釐） (請先閱讀背面之注意事項再填寫本頁) ^-------1訂---------線. 經濟部智慧財產局員工消費合作社印製 418341 A7 B7 五、發明說明（7) 成。在此納入上述出版品所揭露者，係作爲參考。更具體 而言，散光器24含有主材料中之懸浮粒子。該粒子具有與 主材料不同的折射率且係作爲小透鏡。 爲了形成散光器24，可將聚合粒子或小透鏡散佈於整 個第二聚合物’該第二聚合物可視爲主材料或承載基質。 小透鏡粒子和承載基質最好分別具有不同的折射率。在一 實施例中，小透鏡粒子的直徑介於約10至100微米 (micnm)。小透鏡粒子可爲球形、橢圓形，或其他會直接影 響增益剖面之幾何形狀。在一實施例中，小透鏡粒子係由 聚苯乙烯（polystyrene)所構成，以美國測量暨材料學會 (American Society for Testing and Materials, ASTM)所訂定 之D542標準而言，其折射率約介於1.55至1.60之間。承 載基質則可由聚丙嫌（polypropylene)、聚乙嫌 (polyethylene)、多碳酸脂(polycarbonate)或其相似物來形成 ，且其折射率不同於小透鏡粒子。以D542 ASTM標準而 言，承載基質的折射率以小於約1.54較佳。 小透鏡粒子可以許多種方式散佈於整個承載基質。例 如，小透鏡粒子與聚合前之單體(monomer)溶液混合，而後 使該溶液聚合成一遍佈小透鏡粒子之固體承載物。.在一種 情況當中，小透鏡粒子之聚合物的熔解溫度與承載基質的 熔解溫度相差很大，且承載基質在較低的溫度下熔解，固 體狀小透鏡粒子或小顆粒狀物(pellet)即與承載基質相混合 。例如，承載物藉由擠壓（extrusion)或射出（injection)而熔 化或液化，且不需熔化小透鏡粒子。在另一種方式中，小 9 本紙張尺度適用中國國家標準（CNS)A4規格（210 X 297公釐） (請先閲讀背面之沒意事項禹填寫本買> 經濟部智慧財產局負工消費合作社印製 H ϋ ^eJI If n n n I —^r ϋ t— n n 418341 Α7 Β7 五、發明說明（g) 透鏡粒子可以固體型態噴塗於與一液體膠黏劑相混合之襯 墊層(backing layer)上，而後該液體膠黏劑即成爲承載基質 〇 光學兀件22以擠壓塑造(compression molded)或雕凸 於散光器24較佳。有許多種方法可精確地形成Fresnei微 細構造之摺疊於散光器24。在較佳的實施方法中，散光器 與Fresnel透鏡壓型(tooling)係在強壓下（damp pressure)進 行加熱或冷卻階段。 在加熱階段中，散光器材料被軟化或使其溫度上升至 大於或等於散光器基質的玻璃轉變溫度（glass transition temperature，Tg);在一實施例中，此溫度係介於約攝氏49 度至191度之間(華氏12〇度至375度之間）。強壓的範圍 則最好介於約 689.5 至 17,926.4 kPa (100 至 2,600psi)，以 使散光器材料與壓型在整個摺疊複製的過程中能夠保持接 觸，並且迫使散光器基質塡入或準確地摺疊複製微細的 Fresnei透鏡面。在最後的冷卻階段中，降低散光器基質與 Fresnel壓型的溫度至小於散光器之玻璃轉變溫度，以使透 鏡從Fresnel壓型表面釋出。 散光器24可加以修改，使其適於提供對稱或非對稱的 剖面。例如，對於一家庭劇場背面式投影電視而言，吾人 希望擁有非常寬廣的水平視野圓錐體，以便觀賞者能夠坐 在室內中的任何位置。此外，吾人亦希望提供高亮度影像 ，使其在良好地光照條件下提供足夠的對比。提供寬廣的 垂直視野圓錐體則非吾人所需，因爲照射在地板或天花板 10 本紙張尺度適用中國國家標準（CNS)A4規格（210 X 297公釐） <請先閲讀背面之注意事項再填寫本頁) 訂- --線· 經濟部智慧財產局員工消費合作杜印製 A7 經濟部智慧財產局貝工消費合作社印製 418341 _______B7___ 五、發明說明（？） .的光線在實質上係一種浪費。在此例中，散光器被修改使 其最高增益値以及水平視角得以增強，但緊縮垂直視角。 舉例而言，非對稱增益性能可經由利用擠壓或吹氣鑄造法 (blow molding)，將所產生的散光器24延展至一優先的方 向，或經由模壓(pressing)該材料並藉由抑制其流向其它方 向而使其流向一較優先的方向。其它提供非對稱增益性能 的方法，包括利用非圓形小透鏡透過重力、離心力或其他 方法以選擇性地定其方向。額外的微細表面，例如稜鏡與 雙凸透鏡，可配合影像螢幕20 ’以提供如觀看面範圍內之 非對稱性能以及其他特別訂製之增益分布的偏斜補整 (compensation) ° .實例一： 吾人可得到下列對稱與非對稱之增益剖面。 最高增益(Peak Gain) 水平半角(Horizontal Half Angle) 垂直半角(Vertical Half Angle) 1.0 54° 50。 1.5 45。 45〇 2.5 40。 10。 3.5 30。 15。 5.0 40。 7° 實例二： ~ Fre.sne丨透鏡塑成於一以懸浮於聚丙烯之聚苯乙烯 珠（bead)所製成之散光器中。光輸出係利用光測角器 <請先閱讀背面之注意事項再填寫本頁)• V This paper size is in accordance with Chinese National Standard (CNS) A4 (210 X 297 mm) (谙 Please read the notes on the back before filling in this page) ^ 1 ^ 1 ί · 1 nn I nnn I i ~ Ministry of Economic Affairs Wisdom Printed by the Consumer Cooperative of the Property Bureau 418341 _____ B7 V. Description of the Invention ($) The diffuser includes a polymeric carrier substrate and polymeric lenslet particles dispersed throughout the carrier substrate. The lenslet particles can be spherical, elliptical, or other geometric shapes that directly affect the gain profile. The lenslet particles and the carrier substrate preferably have different refractive indices, respectively. In one embodiment, the refractive index of the lenslet particles is between about 1.55 and 1.60, and the refractive index of the carrier matrix is less than about 1.54. The front surface layer may include an anti-reflective coating or a hardcoat thereon. The front surface layer may also include a surface matte or anti-glare processing. The front surface layer contains a neutral density tint to enhance contrast. In another embodiment, the front surface layer includes a reflective surface that redirects light passing through the optical element and the diffuser. This reflective surface may include either a linear or a cube-corner. The projection screen of the present invention can be used in a front-type or rear-type image projection system, and the projection screen of the present invention can greatly reduce or eliminate Fresnel-type ghosting. This projection screen also has the advantage of being lightweight. Compared with the conventional system, it requires fewer assembly steps and therefore has a lower cost. Brief Description of the Drawings A more detailed description of the foregoing preferred embodiments of the present invention will be used to illustrate the foregoing and other objects, technical features, and advantages of the present invention. As shown in the attached drawings, the same reference symbols refer to the same part from different perspectives. The drawings are not necessarily required to emphasize the principle of the present invention in proportion to the scale. 5 This paper size applies to China National Standard (CNS) A4 specification (210 X 297 meals) < Please read the notes on the back before filling this page) i -------- Order ------ --- line. Printed by the Consumer Cooperatives of the Intellectual Property Bureau of the Ministry of Economic Affairs 416341 A7 B7 V. Description of the invention (Ψ) (Please read the precautions on the back before filling this page) Figure 1 is for the back-type imaging system 2 is an enlarged view of the area in FIG. 1 to illustrate the ghost effect 9 FIG. 3 is a side view of an image screen applied to a back-type imaging system according to the present invention; FIG. 4 is an area in FIG. 3 "B " enlarged view; Figure 5 is an isometric view of an image screen, which illustrates the first reference point for measuring the light output from the image screen; Figure 6 is a graph , Which illustrates the gain distribution of the horizontal and vertical angles observed from the center of an image screen; Figure 7 is an isometric view of an image screen, which illustrates the first measurement of the light output from the image screen. 2 reference points; line-Figure 8 is a diagram illustrating the diagram from the outer edge of an image screen Observed gain distribution. Symbol description for printed components of the Consumer Cooperatives, Intellectual Property Bureau, Ministry of Economic Affairs 10 Fresnel lens 11 Input surface 12 Image screen 14 Diffuser 16 Front surface layer 18 Vertical plate surface 20 Image screen 22 Optical components (6 papers Applicable standards_National Standards (CNS) A4 specifications (2ΐα X 297 mm) 4 183 4 1 A7 B7 V. Description of the invention (Evening) 24 Diffuser 26 Surface layer '28 Input end 30 Viewing end 32 Rear projection screen TV _ 34 Projection system 36 Lens system 38 Face mirror 40 Face mirror Detailed description of the preferred embodiment of the invention The detailed description of the preferred embodiment of the present invention is as follows. Figure 3 illustrates a preferred embodiment of an image screen 20, which is used for Like the front and rear projection systems. The image screen 20 includes an optical element 22 integrally formed on the diffuser 24, and the diffuser is preferably laminated on the front surface layer 26. The optical element 22 may include a Fresnel lens, a pair of Convex lens array, chirped or similar, the optical element allows the irradiated light to travel or turn in parallel. The light preferably passes through the optical element 22 and the diffuser 24. The projection system at the input 2S of the curtain 20 forms a collimated image obtained by the optical element 22. The collimated image diffuses a specific gain profile to an output end through a diffuser 24, that is, Viewing end 30. The front surface layer 26 containing acrylic, glass, or the like may contain a neutral density hue to enhance contrast. The front surface layer 26 may also include an anti-reflective coating and / or a hard coating after processing Layer, and the coating is preferably located on the outermost layer facing the viewing end 30. The front surface layer 26 may also include a surface 7 The paper size is applicable to the Chinese National Standard (CNS) A4 specification (210 X 297 mm) < Please read the precautions on the back before filling this page) ^ ------ --Order --------- line. Printed by the Consumer Cooperatives of the Intellectual Property Bureau of the Ministry of Economic Affairs-I ί a— < 1 na— un 418341 A7 B7 V. Description of the invention (ruded) Crude saccharification or anti-売 Light processing. In another embodiment, the front surface layer 26 includes a reflective surface that redirects light passing through the optical element 22 and the diffuser 24. In one embodiment, the reflective surface may include linear chirps, as disclosed in U.S. Patent No. 3,846,012, issued to Brown on November 5, 1974, and U.S. Patent No. 4,260,220, issued to Whitehead on April 7, 19W. The disclosures of the two approved patent cases are incorporated herein for reference. In another embodiment, the reflective surface comprises a cube of angled cubes, such as US Patent No. 3,712,706 issued to Stamm on January 23, 1973, US Patent No. 3,684,348 issued to Rowland on August 14, 1972, and As disclosed in US Patent No. 3,689,346 issued to Rowland on September 5, 1972. The disclosures of each approved patent case are included here for reference. Fig. 4 is an illustration of an optical element 22 formed on a diffuser 24 according to the present invention. In this embodiment, the optical element face faces the incident light from the projection system so that the light passes through point A. The light passing through the point A is irradiated to the point B on the optical element 22, and the lens refracts the light to a parallel direction. The light then hits point C on the diffuser 24; here, the light diverges to the output space D at a wide solid angle. The bevel portion of the optical element 22 does not cause any ghosting. The draft or riser portion of the optical element 22 does cause loss and scattering of light, but this scattered light is messy and does not form any secondary image. The diffuser 24 can be shaped according to the materials disclosed in International Publication No. WO 96/20419 published on July 4, 1996 in accordance with the Patent Cooperation Agreement. 8 This paper size applies the Chinese National Standard (CNS) A4 specification (210 x 297 mm). Li) (Please read the notes on the back before filling out this page) ^ ------- 1 Order --------- line. Printed by the Consumer Cooperatives of the Intellectual Property Bureau of the Ministry of Economic Affairs 418341 A7 B7 5 2. Description of the invention (7). The disclosures of the above publications are incorporated herein by reference. More specifically, the diffuser 24 contains suspended particles in the host material. This particle has a refractive index different from that of the main material and acts as a lenslet. To form the diffuser 24, polymeric particles or lenslets can be dispersed throughout the second polymer ' which can be considered as a main material or a support matrix. The lenslet particles and the carrier matrix preferably have different refractive indices, respectively. In one embodiment, the lenslet particles have a diameter between about 10 and 100 micrometers (micnm). The lenslet particles can be spherical, elliptical, or other geometric shapes that directly affect the gain profile. In one embodiment, the lenslet particles are made of polystyrene. According to the D542 standard set by the American Society for Testing and Materials (ASTM), the refractive index is about Between 1.55 and 1.60. The support matrix can be formed from polypropylene, polyethylene, polycarbonate, or the like, and its refractive index is different from that of lenslet particles. In terms of the D542 ASTM standard, the refractive index of the support matrix is preferably less than about 1.54. Lenslet particles can be dispersed throughout the carrier matrix in a number of ways. For example, the lenslet particles are mixed with a monomer solution before polymerization, and the solution is polymerized to form a solid support throughout the lenslet particles. In one case, the melting temperature of the polymer of the lenslet particles is very different from the melting temperature of the carrier matrix, and the carrier matrix is melted at a lower temperature. The solid lenslet particles or pellets are Mix with carrier matrix. For example, the carrier is melted or liquefied by extrusion or injection without melting the lenslet particles. In another way, the small 9 paper size is applicable to the Chinese National Standard (CNS) A4 specification (210 X 297 mm) (please read the unintentional matter on the back first and fill in this purchase). Printed by the cooperative H ϋ ^ eJI If nnn I — ^ r ϋ t— nn 418341 Α7 Β7 V. Description of the invention (g) The lens particles can be sprayed in solid form on a backing layer mixed with a liquid adhesive ), And then the liquid adhesive becomes the carrier matrix. The optical element 22 is preferably compression molded or embossed on the diffuser 24. There are many ways to accurately form the fine-structured Fresnei fold on Diffuser 24. In a preferred implementation method, the diffuser and Fresnel lens tooling are heated or cooled under a damping pressure. During the heating phase, the diffuser material is softened or its temperature is increased. Rise to a glass transition temperature (Tg) greater than or equal to the diffuser substrate; in one embodiment, the temperature is between about 49 degrees and 191 degrees (between 120 and 375 degrees Fahrenheit) ). The range of strong pressure is preferably between about 689.5 to 17,926.4 kPa (100 to 2,600 psi), so that the diffuser material and the profile can maintain contact during the entire folding and copying process, and force the diffuser substrate to be inserted or accurate. The fine Fresnei lens surface is folded and copied. In the final cooling stage, the temperature of the diffuser substrate and the Fresnel profile is lowered to a temperature lower than the glass transition temperature of the diffuser, so that the lens is released from the Fresnel profiled surface. The diffuser 24 may Modify it to fit a symmetrical or asymmetrical profile. For example, for a home theater rear projection TV, I would like to have a very wide horizontal field of view cone so that viewers can sit anywhere in the room In addition, I also hope to provide high-brightness images to provide sufficient contrast under good lighting conditions. Providing a wide vertical field of view cone is not my need, because it is illuminated on the floor or ceiling. Standard (CNS) A4 specification (210 X 297 mm) < Please read the notes on the back before filling in this ) Set - -?. Line Ministry of Economic Affairs Intellectual Property Office staff consumer cooperatives printed A7 Ministry of Economic Affairs Intellectual Property Office HIGHLAND consumer cooperatives printed 418341 _______B7___ V. description of the invention () light in essentially a waste system. In this example, the diffuser was modified to increase its maximum gain and horizontal viewing angle, but tightened the vertical viewing angle. For example, asymmetric gain performance can be achieved by using extrusion or blow molding to extend the diffuser 24 produced to a preferred direction, or by pressing the material and suppressing it Flow in other directions to make it flow in a preferred direction. Other methods of providing asymmetric gain performance include the use of non-circular lenslets to selectively orient them through gravity, centrifugal force, or other methods. Additional micro-surfaces, such as 双 and lenticular lenses, can be used with the image screen 20 'to provide asymmetric compensation such as asymmetric performance in the viewing surface range and other customized gain distributions. Example 1: Myself The following symmetrical and asymmetric gain profiles can be obtained. Peak Gain Horizontal Half Angle Vertical Half Angle 1.0 54 ° 50. 1.5 45. 45〇 2.5 40. 10. 3.5 30. 15. 5.0 40. 7 ° Example 2: ~ Fre.sne 丨 The lens is molded in a diffuser made of polystyrene beads suspended in polypropylene. Light output uses a light goniometer < please read the notes on the back before filling this page)
本紙張尺度適用中國國家標準（CNS)A4規格（210 X 297公釐） 經濟部智慧財產局員工消費合作社印製 418341 A7 B7 五、發明說明（r ) (goniophotometer)在不同的水平與垂直視角來加以量測’ 並定義垂直於螢幕者爲零度。首先，測量螢幕中央的光輸 出，如圖5所示。在螢幕的中央’ Fresnel透鏡之作用較小 。水平與垂直對稱增益剖面係繪製於圖6。 圖7所示者爲營幕邊緣之量測。圖8所不之結果係圖 解兩種情形：具有Fresnel透鏡之影像螢幕以及不具有 Fresnel透鏡之影像螢幕。在不具有Fresnel透鏡的情況下 ，在邊緣處，光從螢幕射出的角度並不垂直於螢幕。因此 ，坐於垂直於螢幕之觀看者，在朝向螢幕觀看時，將會在 螢幕的邊緣看到一黑暗的角落。藉由附加Fresnel透鏡，光 經過透鏡的準直作用而以垂直於螢幕的方式射入散光器中 。上述的結果係形成一以垂直於螢幕之方向爲中心的光輸 出分布，而其實用的益處係在於增加螢幕上的亮度均勻性 。以專門術語而言，其係被測量作爲降低「中心至邊緣減 少量」（“center-to-edge fall off’）。 圖9係圖示一示範性的背面式投影螢幕電視32，其包 含投影系統34，且投影系統34經過一透鏡系統36將一影 像投射出。而後該影像藉由面鏡38與4〇反射至影像螢幕 20 以上所揭露之本發明的較佳實施例僅係用以說明，熟 習此項技術者可根據以上所述之實施例進行變更、替換或 潤飾’但仍不脫離本發明所附之專利申請範圍所涵蓋的範 圍。 .. 12 本紙張尺度適用中國國家標準（CNS)A4規格（210x297公爱〉 {請先閲讀背面之注意事項再填寫本頁) V,--!1—訂------！ 線^This paper size is in accordance with Chinese National Standard (CNS) A4 (210 X 297 mm). Printed by the Consumer Cooperatives of the Intellectual Property Bureau of the Ministry of Economic Affairs. 418341 A7 B7. 5. Description of the invention (r) (goniophotometer) Measure it 'and define it as zero degrees perpendicular to the screen. First, measure the light output in the center of the screen, as shown in Figure 5. In the center of the screen, the Fresnel lens is less effective. The horizontal and vertical symmetrical gain profiles are plotted in Figure 6. Figure 7 shows the measurement of the edge of the camp screen. The results shown in Figure 8 illustrate two scenarios: an image screen with Fresnel lenses and an image screen without Fresnel lenses. Without a Fresnel lens, at the edges, the angle at which light exits from the screen is not perpendicular to the screen. Therefore, a viewer sitting perpendicular to the screen will see a dark corner at the edge of the screen when looking at the screen. With the addition of a Fresnel lens, light passes through the collimation of the lens and enters the diffuser perpendicular to the screen. The above results form a light output distribution centered on the direction perpendicular to the screen, and its practical benefit is to increase the brightness uniformity on the screen. In technical terms, it is measured as a reduction of "center-to-edge fall off". Figure 9 illustrates an exemplary rear projection screen television 32, which includes a projection System 34, and the projection system 34 projects an image through a lens system 36. The image is then reflected by the mirrors 38 and 40 to the image screen 20. The preferred embodiment of the present invention disclosed above is only for illustration Those skilled in the art can make changes, replacements, or retouches according to the embodiments described above, but still do not depart from the scope covered by the scope of the patent application attached to the present invention .. 12 This paper standard applies to the Chinese National Standard (CNS ) A4 specifications (210x297 public love) {Please read the precautions on the back before filling this page) V,-! 1—Order ------! Line ^