空间光调制器曲面拼接实现全息三维显示视角拓展

本文对多空间光调制器不同拼接方式拓展全息三维再现像视角的方法进行了分析,基于多片空间光调制器拼接拓展视角的思想,利用平面反射镜、分光镜和两片透射式空间光调制器设计了曲面拼接系统,进行了全息三维再现像的视角拓展实验研究。用该系统对四棱锥物体的层析菲涅尔衍射全息图进行再现,结果表明,总视角由基于单片空间光调制器的1.7°增大到3.2°,即拓展到约1.9倍,分光镜能够消除两片空间光调制器间的间隙,实现无缝拼接。该方法同样适用于更多空间光调制器的曲面拼接中,可以有效地拓展全息再现像的视场角大小。

Viewing angle enlargement in holographic 3D display by spatial light modulators tiling in curved configuration

In this paper, we analyzed the principles of tiling SLMs to enlarge the viewing angle of holographic 3D reconstructions. Based on the idea of tiling multi-SLMs, we designed a holographic 3D display system using planar mirrors, beam splitters and two transmission-type SLMs tiled in curved configuration to enlarge the viewing angle of reconstructed image. We calculated computer-generated holograms of a pyramid using slice-based Fresnel diffraction algorithm, and reconstructed it with self-setup holographic display system. The results indicate that, in contrast to 1.7° of viewing angle obtained by a single SLM, the viewing angle of holographic reconstructed images is enlarged to 3.2° with 2 tiling transmission-type SLMs by about 1.9 times. The beam splitter can remove the gap of two SLMs' active areas to realize seamless tiling. This method is also applicable to tile more SLMs in curved configuration and can effectively enlarge the viewing angle of holographic display.