改良型反射式虛像圓錐複合全像術

黃令杰(ling-chieh huang)

指導教授 ： 鄭益祥

國立中央大學/理學院/光電科學與工程學系/碩士(2015年)

摘要

圓錐型複合全像術是由Okada於1989年領導日本研究團隊所提出，將二維的物體資訊以垂直條紋記錄在全像片上，在重建時會有一條一條垂直的條紋在影像上面，我們稱為「柵欄效應」。本實驗室在先前的研究當中，以「成像面」方式解決了此問題。近年，郭博裕學長提出反射式成像面圓錐型複合全像術，在拍攝之物光與參考光系統加入柱狀透鏡，改善全像片因彎折成圓錐曲面所產生的「像散效應」，增加單張全像片可觀賞影像的範圍，並在觀賞全像影像時，以準值之LED白光光束重建出形變量較小的三維立體影像，但還是會有少許的形變。為了完全解決形變問題，林斯巖學長提出「彎折物面之反射成像面圓錐型複合全像術」，利用影像回推的概念，在拍攝中直接彎折底片成圓錐，避免掉全像片因彎折所產生的「像散效應」，以期能使重建之方塊影像沒有形變。
本論文的重點在於，利用「單步驟反射式成像面圓錐型複合全像術」的概念，將其改良。改良有三大方向：第一、增加全像片的記錄範圍，使記錄物體資訊變大，增加重建影像的大小。第二、保留「彎折物面之反射成像面圓錐複合全像術」影像回推的方式避免影像變形的概念，修改原始物體資訊的圖案使得重建出的三維影像之形變量較小。第三、在重建時，將重建參考光源放置在圓錐頂點上方，利於環繞全像片四周的觀賞者同時觀賞。全像片拍攝完成後以反射式的方式重建，觀賞者將看到一個沉在圓錐內部下方的虛像三維影像。在論文中，我們以電腦模擬影像回推得出待記錄物體資訊的圖形，與重建影像時觀賞者改變位置所觀看到之三維影像的變化。

關鍵字

圓錐複合全像術 ； HASH(0xf9b5870) ； 反射式虛像 ； HASH(0xf9b59b0) ； 全像術

並列摘要

The conical holographic stereogram was developed in 1989 by Japanese research team led by K.Okada. They recoded 2D image information belongs to different angles of the original object in a sequence of long, thin and fan-shaped areas of the recoding film. As a result, the reconstructed image will beover laid by many black stripes. It looks like viewing an image through a fence, called the “picket-fence effect”. This problem can be amended by using the image-plane technique. In the previous study, cylindrical lenses were placed in both the object beam and the reference beam to compensate for the “astigmatic effect’’, produced when hologram is curved into a conical surface, in order to avoid deformation of the 3D image. But the this method still can’t produce perfect 3D image.
In the study, we focus on improving one-step reflection image-plane conic multiplex hologram. We come up with three means to improve it. First, increasing the recorded area of the individual hologram so as to increase the amount of 2D information and enlarge the reconstructed 3D image. Second, using ray tracing to redraw the original 2D image information in order to reduce deformation of the reconstructed 3D image. The last point, we set the white-light point source on the axis of hologram cone during reconstruction so that observer around the hologram can simultaneously watch the 3D image. The 3D virtue image is generated and displayed inside the hologram cone. We use computer to simulate the holographic process and the reconstructed 3D images observed at different positions. Using the propose fabrication method, we succeed in adding recorded range of hologram that used ray tracing to redraw information in order to reduce deformation of 3D image during reconstruction and observer can perceive 3D image more conveniently with flashlight on the axis of holographic cone. Finally, we propose some improved methods and the possibility in the future `development

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