經濟部中央標準局貝工消费合作社印製 321736 A7 -- —-.. ____B7_ 五、發明説明（1 ) 本發明係有關於一種投影銀幕及其製作方法，特別係 有關於一種利用全像干涉法製作的投影銀幕及其製作方 法其係一種具有可將投射光散射成非對稱分佈之細微橢 圓狀凹凸結構的投影銀幕；利用此投影銀幕之細微橢圓狀 凹凸結構的散光特性可使得投影銀幕具有高亮度及寬視角 的效果《 —般的下拉式投影銀幕，底材多為塑膠材料，表面再 链上層白漆或金屬以增加散射反光率，此種銀幕的散光 方式疋圓對稱的。也就是說，當光源1投射光束5打在銀 幕表面10後會向四面八方均勻散射，如第1圖所示，此種 銀幕可以將投影的影像均勻地在垂直和水平方向散射，適 用於觀眾較多且觀賞位置分布寬廣的場所，例如電影院。 但疋也因為這種銀幕的水平與垂直的散射角都很大，故其 具有影像报暗的缺點，必須在暗室中才能觀赏影像。 不過’由於有些場所觀賞位置分布較為集中，所以並 非所有的場所都希望所用的銀幕以此均勻圓對稱的方式散 射影像°以會議室為例，其觀眾的位置分布便較為集中， 所· Μ $需將光散射到特定的位置上即可 。如此，因為光的 散射分布較為集中，故也就同時可改善習知投影影像太暗 的缺點。 習知技藝中，有下列幾種方式用來製作這種特殊的投 影銀幕。第一、請參閱第2圖，其係以一 Fresnel透鏡20 將光準直’並用複數個凸透鏡狀（lenticular)的柱形透鏡25 將光作單方向的擴散，以得到成形（shaping)的效果。然而， 本紙張尺度適用中國國家榡準（CMS ) A4規格（210X297公釐） -----------^------tT------^ (請先閲讀背面之注意事項再填寫本頁) 經濟部中央橾準局貝工消费合作社印装 321736 A7 ---------B7 五、發明説明（2 ) ~~---- 此種方式卻具有製作成本高 取不w、量產不易及成形效果控制困 難等缺點。 凊參閱第圖’第一種習知技藝係揭露於美國專利第 5,365,354號中’其係利用將特殊結構的細小物質30，以 體積型（V〇lume)方式植入基材％巾形成小斑點⑽㈣) 以使其具有垂直於表面的漸變折射率’藉以得到成形的效 果C疋此種I知技藝製作成本極高且極不容易進行量 產，產業上的實用性有限。 請參閱第4圖，第三種習知技藝係揭露於中華民國專 利第228577號中’其主要係以一金屬板材4〇之銀幕經多 次壓延抽拉或報壓研磨，以使銀幕表面產生高密度之條紋 41，而形成銀幕之反射面呈高低起伏狀，使得垂直方向之 入射光可以定向反射，水平方向之入射光可以擴散反射， 因而可以產生水平視角寬廣，而垂直增益提高的效果。另 外，銀幕形成為沿垂直方向弩曲的柱面形，以使亮度分佈 均勻’同時排斥外來光的干擾。雖然，此種機械加工的方 式可以將投影銀幕的製作控制在較低的成本，不過，由於 加工時須製作在曲面上，所以較難進行量產，且由於其高 密度條紋係利用多次壓延抽拉或輥壓研磨而形成，故其非 常不易控制成形的效果。 有鑑於此，為了改進習知技藝的缺點，提昇此類產品 的實用性，本發明之目的即在於提出一種以全像干涉法製 作的投影銀幕及其製作方法’其係一種以全像干涉法在感 光物質上曝光，來製作可將投射光散射成非對稱分佈的細 本紙張尺度適用中國國家標準（CNS ) A4规格（2丨〇x297公釐） -----------餐------、tr------0 (請先閲讀背面之注意事項再填寫本頁) 經濟部中央標準局員工消费合作社印裝 321736 A7 B7 五、發明説明（3 ) 微橢圓狀凹凸結構的方法，以及利用此微小橢圓狀凹凸結 構之散光特性所製作出高亮度、寬視角、高效率的投影銀 幕。可做為投影機、液晶投影電視、幻燈機，甚至是電影 等的反射幕。 本發明之另一目的即在於提出一種以全像干涉法製作 的投影銀幕及其製作方法，其在量產時可先製成模具後用 熱壓的方式大量生產，製程簡單，可降低製作成本。 本發明之再一目的即在於提出一種以全像干涉法製作 的投影銀幕及其製作方法，其可隨意控制曝光的模式來製 作出不同散射角比例的銀幕，以製作適用於不同規格、不 同場合要求的投影銀幕。 下面就配合附圖說明本發明的較佳實施例，藉以進一 步說明本發明之步驟、優點及特點，其中： 第1圖係繪示應用習知下拉式投影銀幕之散射光分佈 情形的圖式； 第2圖係繪示一習知的投影銀幕之架構的圖式； 第3圖係繪示另一習知的投影銀幕之架構的圖式； 第4圖係繪示再一習知的投影銀幕之架構的圖式； 第5圖係繪示本發明用以製作一投影銀幕的裝置之架 構圖式； 第6圖係繪示本發明之投影銀幕的示意圖；及 第7圖係繪示本發明之投影銀幕的散射光分佈強度的 圖式。 較佳實施例的說明： 本紙張尺度適用中國國家標準（CNS ) A4规格（210 X 297公釐） . 裝 訂 線 (請先閲讀背面之注意事項再填寫本頁) 經濟部中央揉準局貝工消費合作社印装 321736 A7 B7 五、發明説明（4 ) 請參閱第5圖，本發明用以製作一投影銀幕的裝置係 包括：一雷射光源50、一快門52、一第一柱狀透鏡54、 一第二柱狀透鏡56、一光罩58、一毛玻璃60及感光底片 62。其中，快門52係用以控制感光底片62的曝光時間； 而第一柱狀透鏡54及第二柱狀透鏡56則係用以將圓形口 徑的光束調整成橢圓形口徑的光束；毛玻璃60係用以將橢 圓形口徑的光束散射成複數個微小橢圓形光點；而光罩58 係用以遮去光束周圍不必要的雜訊。 在本發明用以製作一投影銀幕的裝置之一較佳實施例 中，第一柱狀透鏡54的焦距為75mm，第二柱狀透鏡56 的焦距為25.4mm，且毛玻璃60與第一柱狀透鏡54、第 二柱狀透鏡56以及感光底片62之間的設置關係為毛玻璃 60與第一柱狀透鏡54相距60cm ;毛玻璃60與第二柱狀 透鏡56相距47cm ;而毛玻璃60與感光底片62間則相距 26.5cm 。 利用如前述第5圖之設置，並按照下述方法可製作出 本發明之投影銀幕，其包含下列步驟：（1)使雷射光50 通過一快門52，藉以利用快門52控制曝光時間，以使感 光底片62得到適當的曝光量；（2)利用一第一柱狀透鏡54 及一第二柱狀透鏡56水平及垂直地設置於雷射光的路徑 上，藉以對雷射光作垂直方向及水平方向的擴展，並可縮 短曝光時間；（3)使擴展成一橢圓狀的雷射光打在一覆蓋有 長方形光罩58的毛玻璃60上，藉以形成複數個微細橢圓 形光點，並用以使位於毛玻璃60後方的感光底片62曝光； 6 本紙張尺度適用中國國家標準（CNS ) A4規格（210X297公釐） !|, I I I 裝 I I I I 訂 I I 線 (讀先閱讀背面之注意事項再填寫本頁) 321736 經濟部中央揉準局貝工消費合作社印製 A7 —_____B7___五、發明説明（5 ) (4)將曝光完成的底片62顯影，藉以在底片62上面形成複 數個高低起伏的微細橢圓顆粒，如第6圖所示；（5)將此底 片電鑄成鎳板，然後架在滚筒上以滾壓於一金屬鍍膜上。 在前述步驟（5)中電鱗後所得的鎳板，也可以利用平壓 法或射出法，先將細小的橢圓形凹凸結構製作於熱塑性材 料後，再作金屬鍍膜。由於模具製作完成後，便可利用熱 壓的方式進行量產，製程簡單，可減少產品的成本。 再者，在上述的製作方法中，藉由調整第一柱狀透鏡 54和第二柱狀透鏡56的組合，以及毛玻璃60的粗細’可 以改變橢圓顆粒的形狀，藉以製作出具不同規格發散角的 銀幕。換句話說，本發明可隨意控制曝光的模式來製作出 具不同散射角比例的銀幕，亦即町製作適用於不同場合之 要求的不同規格的銀幕。 對利用前述方法之步驟（5)所製作出的鎳板進行散射 光強度分布的量測，並將其與市面上可取得的投影銀幕 (3M公司的Wall Screen)的散射光強度分布加以比較。量測 時係採用照度計（SEK〇NIC公司的DIGI LITE Model L-318B)在距離中心約1公尺的弧上進行量測，另外須注意投 影區域要限制在有效的散光區域，真投影在前述鎳板及投 影銀幕上的光量必須相同。所得到的結果如第7圖所示， 其中’曲線A及曲線B分別表示前述錄板的水平及垂直散 射光的分佈，而曲線C則係表示一般投影銀幕的散射光強 度分佈。由圖中可知本發明之投影銀幕，其散射光強度的 分布在水平方向視角為100。（1/10峰值處的全角），可提供 7 本紙張纽適用中關(CNS) A4^ (21GX297公麓） — (請先閲讀背面之注意事項再填寫本頁) 裝. 訂 線 321736 A7 B7 經濟部中央梯準局負工消費合作社印製 五、發明説明（6 ) 足夠的寬視角；在垂直方向則為40°，使散射光集中，其 峰值較習知的投影銀幕提高約5倍。 (請先閱讀背面之注意事項再填寫本頁) -裝_ 訂 本紙張尺度適用中國國家標準（CNS〉A4規格（210X297公釐）Printed by Beigong Consumer Cooperative of the Central Bureau of Standards of the Ministry of Economic Affairs 321736 A7 ---- .. ____B7_ V. Description of the invention (1) The present invention relates to a projection screen and its production method, in particular, it relates to a method using holographic interference The manufactured projection screen and the manufacturing method thereof are projection screens with a fine elliptical concave-convex structure that can scatter the projected light into an asymmetric distribution; using the astigmatism characteristics of the fine elliptical concave-convex structure of the projection screen can make the projection screen have a high The effect of brightness and wide viewing angle is "a general pull-down projection screen, the substrate is mostly plastic material, and the surface is chained with white paint or metal to increase the scattering reflection rate. This screen's astigmatism is circularly symmetrical. In other words, when the light source 1 projects the light beam 5 on the screen surface 10, it will be evenly scattered in all directions. As shown in Figure 1, this type of screen can evenly scatter the projected image in the vertical and horizontal directions, which is suitable for audiences. There are many places with wide viewing positions, such as movie theaters. However, because the horizontal and vertical scattering angles of this screen are very large, it has the disadvantage of reporting dark images, and the images must be viewed in a dark room. However, 'as some places have more concentrated viewing positions, not all places want the screens used to scatter images in a uniformly circularly symmetrical way. Taking the conference room as an example, the location of the audience is more concentrated, so Μ $ The light needs to be scattered to a specific location. In this way, because the scattering distribution of light is relatively concentrated, it can also improve the disadvantage that the conventional projection image is too dark. In the conventional art, there are several ways to make this special projection screen. First, please refer to Figure 2, which uses a Fresnel lens 20 to collimate the light and use a plurality of lenticular cylindrical lenses 25 to diffuse the light in one direction to obtain the shaping effect . However, this paper scale is applicable to the Chinese National Standard (CMS) A4 specification (210X297mm) ----------- ^ ------ tT ------ ^ (please read first (Notes on the back and then fill out this page) Printed 321736 A7 --------- B7 of the Beigong Consumer Cooperative of the Central Bureau of Economic Affairs of the Ministry of Economic Affairs V. Invention description (2) ~~ ---- It has the disadvantages of high production cost, difficulty in mass production and difficult control of forming effect. Refer to the figure "The first type of conventional art is disclosed in US Patent No. 5,365,354" which uses a small structure 30 of a special structure to implant into a base material in a volumetric (Vlume) way to form small spots ⑽ (iv) To make it have a graded refractive index perpendicular to the surface, so as to obtain the effect of molding C. This kind of know-how is extremely expensive to manufacture and extremely difficult to mass-produce, and its industrial applicability is limited. Please refer to Fig. 4, the third type of conventional art is disclosed in the Republic of China Patent No. 228577, which mainly uses a metal sheet 40 screen through multiple calendering or press grinding to make the screen surface The high-density fringes 41 and the reflection surface forming the screen are undulating, so that the incident light in the vertical direction can be directionally reflected, and the incident light in the horizontal direction can be diffused and reflected, thereby producing a wide horizontal viewing angle and an increase in vertical gain. In addition, the screen is formed into a cylindrical shape that crosses in the vertical direction to make the brightness distribution uniform 'while repelling interference from external light. Although this type of mechanical processing can control the production of projection screens at a lower cost, it is difficult to mass-produce due to the fact that it must be made on a curved surface during processing, and because of its high-density stripe system, multiple calendering is used It is formed by drawing or rolling grinding, so it is very difficult to control the forming effect. In view of this, in order to improve the shortcomings of the conventional techniques and enhance the practicality of such products, the purpose of the present invention is to propose a projection screen manufactured by holographic interferometry and its manufacturing method 'which is a method of holographic interferometry Expose on the photosensitive material to make thin paper that can scatter the projected light into an asymmetric distribution. The size of the paper is applicable to the Chinese National Standard (CNS) A4 specification (2 x 297mm) ----------- Meal ------, tr ------ 0 (please read the precautions on the back before filling in this page) Printed 321736 A7 B7 by the Employees Consumer Cooperative of the Central Bureau of Standards of the Ministry of Economy V. Description of Invention (3) Micro The method of the elliptical concavo-convex structure, and the use of the astigmatism characteristics of the tiny elliptical concavo-convex structure to produce a projection screen with high brightness, wide viewing angle and high efficiency. Can be used as a reflective screen for projectors, LCD projection TVs, slide projectors, and even movies. Another object of the present invention is to propose a projection screen manufactured by holographic interference method and its manufacturing method, which can be made into a mold and then mass-produced by hot pressing in mass production. The manufacturing process is simple and the manufacturing cost can be reduced . Another object of the present invention is to propose a projection screen made by holographic interference and its manufacturing method, which can control the exposure mode at will to make screens with different ratios of scattering angles to make them suitable for different specifications and different occasions The required projection screen. The following describes preferred embodiments of the present invention with reference to the accompanying drawings, so as to further illustrate the steps, advantages, and features of the present invention. Among them: FIG. 1 is a diagram showing the distribution of scattered light in a conventional pull-down projection screen; Figure 2 is a diagram showing the structure of a conventional projection screen; Figure 3 is a diagram showing the structure of another conventional projection screen; Figure 4 is a drawing of another conventional projection screen Figure 5 is a schematic diagram of an apparatus for manufacturing a projection screen of the present invention; Figure 6 is a schematic diagram of a projection screen of the present invention; and Figure 7 is a schematic diagram of the present invention The pattern of the scattered light distribution intensity of the projection screen. Description of the preferred embodiment: This paper standard is applicable to the Chinese National Standard (CNS) A4 (210 X 297 mm). Binding line (please read the precautions on the back before filling out this page) Ministry of Economic Affairs Central Bureau of Standardization and Development Printed by the consumer cooperative 321736 A7 B7 V. Description of the invention (4) Please refer to FIG. 5, the device for manufacturing a projection screen of the present invention includes: a laser light source 50, a shutter 52, a first cylindrical lens 54 , A second lenticular lens 56, a mask 58, a frosted glass 60 and a photosensitive negative film 62. The shutter 52 is used to control the exposure time of the photosensitive film 62; the first lenticular lens 54 and the second lenticular lens 56 are used to adjust the circular aperture beam to an elliptical aperture beam; the frosted glass 60 series It is used to scatter the elliptical aperture beam into a plurality of tiny elliptical light spots; and the mask 58 is used to block unnecessary noise around the beam. In a preferred embodiment of the device for manufacturing a projection screen of the present invention, the focal length of the first cylindrical lens 54 is 75 mm, the focal length of the second cylindrical lens 56 is 25.4 mm, and the frosted glass 60 and the first cylindrical shape The arrangement relationship between the lens 54, the second lenticular lens 56 and the photosensitive negative film 62 is that the ground glass 60 and the first cylindrical lens 54 are separated by 60 cm; the ground glass 60 and the second cylindrical lens 56 are separated by 47 cm; and the ground glass 60 and the photosensitive negative film 62 The distance between them is 26.5cm. The projection screen of the present invention can be made using the settings as shown in FIG. 5 and in accordance with the following method, which includes the following steps: (1) The laser light 50 is passed through a shutter 52, and the shutter 52 is used to control the exposure time so that The photosensitive film 62 is properly exposed; (2) A first lenticular lens 54 and a second lenticular lens 56 are arranged horizontally and vertically on the path of the laser light, so as to make the laser light vertical and horizontal Expansion, and can shorten the exposure time; (3) make the laser light expanded into an ellipse hit a frosted glass 60 covered with a rectangular mask 58 to form a plurality of fine elliptical light spots, and used to locate the frosted glass 60 The photosensitive film 62 on the rear is exposed; 6 The size of the paper is in accordance with the Chinese National Standard (CNS) A4 (210X297mm)! |, III Pack IIII Order II line (read the precautions on the back and then fill out this page) 321736 Ministry of Economic Affairs Printed by the Central Bureau of Precision Industry Beigong Consumer Cooperative A7 —_____ B7___ V. Description of the invention (5) (4) Develop the exposed negative film 62 to form multiple heights on the negative film 62 The undulating fine elliptical particles are shown in Figure 6; (5) The negative film is electroformed into a nickel plate, which is then placed on a roller to be rolled on a metal coating. The nickel plate obtained after electroscaling in the aforementioned step (5) can also be made of a thin elliptical concave-convex structure on a thermoplastic material by flat pressing or injection method, and then subjected to metal plating. After the mold is manufactured, mass production can be performed by hot pressing, and the manufacturing process is simple, which can reduce the cost of the product. Furthermore, in the above manufacturing method, by adjusting the combination of the first lenticular lens 54 and the second lenticular lens 56, and the thickness of the frosted glass 60 ', the shape of the elliptical particles can be changed to produce different specifications of divergence angles screen. In other words, the present invention can arbitrarily control the exposure mode to produce screens with different ratios of scattering angles, that is, to produce screens of different specifications suitable for different occasions. The scattered light intensity distribution of the nickel plate produced by the step (5) of the aforementioned method was measured, and compared with the scattered light intensity distribution of a commercially available projection screen (3M Company's Wall Screen). When measuring, an illuminance meter (DIGI LITE Model L-318B from SEK〇NIC) is used to measure on an arc about 1 meter away from the center. In addition, the projection area must be limited to the effective astigmatism area. The true projection is The amount of light on the aforementioned nickel plate and projection screen must be the same. The results obtained are shown in Figure 7, where 'curve A and curve B respectively represent the horizontal and vertical scattered light distributions of the aforementioned recording board, and curve C represents the scattered light intensity distribution of a general projection screen. It can be seen from the figure that the projection screen of the present invention has a scattered light intensity distribution with a viewing angle of 100 in the horizontal direction. (Full angle at 1/10 peak), 7 paper buttons are available for Zhongguan (CNS) A4 ^ (21GX297 foot) — (Please read the precautions on the back before filling out this page) Binding. 321736 A7 B7 Printed by the Ministry of Economic Affairs, Central Bureau of Preservation and Consumer Cooperatives V. Description of invention (6) Enough wide angle of view; 40 ° in the vertical direction, so that the scattered light is concentrated, and its peak value is about 5 times higher than that of the conventional projection screen. (Please read the precautions on the back before filling in this page) -Installation_ Order This paper size is applicable to China National Standard (CNS> A4 specification (210X297mm)