光學膜結構3D漂浮影像系統設計

Abstract

隨著科技的演進，顯示技術也扶搖直上，從早期的平面2D顯示器，發展到現在的各式裸眼3D顯示器，近年來，3D技術的應用更加的多元與廣泛。例如:使用遮光板讓人接收左右眼不同的光以合成3D影像的顯示器、用圓錐狀擴散板讓光在垂直方向擴散以合成具水平視差影像的顯示器等裸眼3D顯示技術。這些3D技術提供了模擬真實世界物體的影像，讓人們在遊戲或是電影中更能身歷其境地享受視覺體驗。 為了讓3D影像看起來更為真實，影像浮出顯示器的距離，景深、視角的大小以及視角範圍內影像的連續性都是系統設計中所需要考慮的重要因素。部分的顯示器視角只包含了螢幕法線方向的小角度範圍且影像也只浮出屏幕表面約略一公分的距離，導致立體視覺效果微弱。而漂浮影像顯示系統產生漂浮在空氣中的3D影像，其視角可高達360度，能改善景深與視角所產生的問題，提升影像的真實性。 本篇論文提出一套基於一維疊加水平視差影像成像原理的漂浮影像系統，利用多台微投影機排列成二維陣列提供環場水平視差的光場，並在其上疊加針孔陣列層與環形透鏡陣列層進行光場分布的重新配置，讓投影機的光通過這兩層光學膜後，產生360度環場水平視差的漂浮影像。

As the progress of technology, display technology improves every day. In the preliminary, there were just 2D displays, but only took few decades, various 3D display technologies contend for attention. In recent years, the applications of 3D display technologies are practicable and comprehensive. For examples, some kinds of display use light barrier to block right eye signal to left eye, and block left eye signal to right eye, which makes two eyes receive different light signal to blend into 3D images. Other kinds use diffuser of cone appearance to diffuse light in vertical direction but keep the discontinuity in horizontal direction, which let users view images of horizontal parallax. These technologies provide images similar to real objects, which gives users a virtual feeling as if it were really happening in movies or computer games. However, to enhance the reality of 3D images, the main factors, depth of view, magnitude of viewing angle, and the continuity of images in viewing angle, are needs to consider. In some displays, the viewing angle just includes small segment in normal direction of display, and images merely emerge 1 cm in front of the screen, which severely weakens the stereo vision and depresses users. The 3D floating display systems generate 3D images floating in the air, and viewing angle are able to get to360 degrees, which mends the issues arising from depth of view and small viewing angle, and further it can enhance image quality. In this study, a floating image display system on account of imaging principle of one-dimensional integral image with horizontal parallax is proposed. In the system, we use multiple micro projector as light source of horizontal parallax system. Each micro projector counts for a portion of viewing angle in azimuthal direction of 360 degrees. On the above of projector layer, we pile up pinhole layer and toroidal lens layer, and the two optical films play the function of rearranging light from projectors. After light passes through them, users move in azimuthal direction are able to see floating image with smooth horizontal parallax.