光子学报, 2013, 42 (12): 1454, 网络出版: 2013-12-16
计算机与光学全息术结合制作大侧视角周视全息图
Circularviewing Hologram with Large Side Viewing Angle Generated by Combining Computer with Optical Holography
摘要
周视全息能够显示物体360°的再现像,因而极具应用价值.为提高平板型周视全息再现像的观看侧视角,并能够白光再现,结合计算全息,提出了制作大侧视角周视全息图的新方法——计算机与光学全息术结合两步法.研究了计算机制平板周视全息的算法原理,推导了物光波的传播规律,并得到它在记录面上的分布图样.讨论了参物夹角对全息图空间频率的影响,设计了第二步光学像面全息拍摄光路,推导了全息图空间频率与物体尺寸及观察视角的关系式,并计算出关系曲线;选用建模的三维灰度物体,用两步法制作了能够实现白光再现的大侧视角周视全息图,从而验证了原理和设计.对于平板型周视全息来说,该设计不仅可以突破光学全息对记录物体的限制,进行虚拟物体或自然场景的全息图的制作,同时又可以提高再现像的侧视角.
Abstract
The circularviewing hologram can show 360° reconstruction of a object, so it has a great application value. For the purpose of increasing the viewingangle of the image and reconstructing it by white light, a new two steps method, Which combined computer with optical holography for making the circularviewing hologram, was proposed considering of the computer generated hologram. First, the algorithm of computer generated circularviewing plane hologram was studied, the propagation principle of object wave was derived, and the distribution pattern of the object wave on the recording plane was obtained meanwhile. Next, the influence of the angle between reference light and object light on spatial frequency of the hologram was discussed, the spatial frequency could be decreased by using a point reference light source, so it could increase the viewingangle. However, the image could only be viewed by laser. To solve this problem and to reconstruct the hologram by white light, optical setup for imageplane hologram was designed as the second step. Then, the relationship between spatial frequency of the hologram and the size of object, and the relationship between spatial frequency of the hologram and the viewing angle were deduced, and the curves of the relationships were also calculated. Finally, a 3D modeling gray object was used and the circularviewing hologram with large side viewing angle which could be reconstructed by white light was made. Therefore, the calculation method and optical design were verified. For circularviewing plane hologram, the technique can record realexisting objects and virtual objects and achieve the image by white light, and it can increase the viewingangle of the reconstruction at the same time.
毋东元, 王辉, 谢裕涛, 杨鑫. 计算机与光学全息术结合制作大侧视角周视全息图[J]. 光子学报, 2013, 42(12): 1454. WU Dongyuan, WANG Hui, XIE Yutao, YANG Xin. Circularviewing Hologram with Large Side Viewing Angle Generated by Combining Computer with Optical Holography[J]. ACTA PHOTONICA SINICA, 2013, 42(12): 1454.