Kozacki Tomasz
Institute of Micromechanics and Photonics, Warsaw University of Technology, 8 Świętego Andrzeja Boboli Street, 02-525 Warsaw, Poland.
Appl Opt. 2011 Jul 10;50(20):3579-88. doi: 10.1364/AO.50.003579.
In this paper, we analyze a holographic display system utilizing a phase-only spatial light modulator (SLM) based on liquid crystal on silicon (LCoS). An LCoS SLM works in reflection, and, in some applications, it is convenient to use with an inclined illumination. Even with a highly inclined illumination, the holographic display is capable of good-quality image generation. We show that the key to obtain high-quality reconstructions is the tilt-dependent calibration and algorithms. Typically, an LCoS SLM is illuminated with a plane wave with normal wave vector. We use inclined illumination, which requires development of new algorithms and display characterization. In this paper we introduce two algorithms. The first one is designed to process a digital hologram captured in CCD normal configuration, so it can be displayed in SLM tilted geometry, while the second one is capable of synthetic hologram generation for tilted SLM configuration. The inclined geometry asymmetrically changes the field of view of a holographic display. The presented theoretical analysis of the aliasing effect provides a formula for the field of view as a function of SLM tilt. The incidence angle affects SLM performance. Both elements of SLM calibration, i.e., pixel phase response and wavefront aberrations, strongly depend on SLM tilt angle. The effect is discussed in this paper. All of the discussions are accompanied with experimental results.
在本文中，我们分析了一种基于硅基液晶（LCoS）的纯相位空间光调制器（SLM）的全息显示系统。LCoS SLM工作在反射模式下，并且在某些应用中，使用倾斜照明很方便。即使采用高度倾斜照明，全息显示仍能够生成高质量图像。我们表明，获得高质量重建的关键在于与倾斜相关的校准和算法。通常，LCoS SLM用具有法向波矢的平面波照明。我们使用倾斜照明，这需要开发新的算法和显示表征方法。在本文中，我们介绍了两种算法。第一种算法旨在处理在电荷耦合器件（CCD）正常配置下捕获的数字全息图，以便它可以在SLM倾斜几何结构中显示，而第二种算法能够为倾斜的SLM配置生成合成全息图。倾斜几何结构会不对称地改变全息显示的视场。所呈现的关于混叠效应的理论分析提供了一个视场作为SLM倾斜函数的公式。入射角会影响SLM性能。SLM校准的两个要素，即像素相位响应和波前像差，都强烈依赖于SLM倾斜角度。本文将讨论这种效应。所有讨论都伴有实验结果。
