Tsang P W M, Poon T-C, Zhou C
Department of Electronic Engineering, City University of Hong Kong, Hong Kong China.
Opt Express. 2013 Jul 29;21(15):17586-91. doi: 10.1364/OE.21.017586.
In this paper, a fast method for displaying a digital, real and off-axis Fresnel hologram on a lower resolution device is reported. Preserving the original resolution of the hologram upon display is one of the important attributes of the proposed method. Our method can be divided into 3 stages. First, a digital hologram representing a given three dimensional (3D) object is down-sampled based on a fix, jitter down-sampling lattice. Second, the down-sampled hologram is interpolated, through pixel duplication, into a low resolution hologram that can be displayed with a low-resolution spatial light modulator (SLM). Third, the SLM is overlaid with a grating which is generated based on the same jitter down-sampling lattice that samples the hologram. The integration of the grating and the low-resolution hologram results in, to a good approximation, the resolution of the original hologram. As such, our proposed method enables digital holograms to be displayed with lower resolution SLMs, paving the way for the development of low-cost holographic video display.
本文报道了一种在较低分辨率设备上显示数字、真实且离轴菲涅耳全息图的快速方法。在显示时保留全息图的原始分辨率是该方法的重要特性之一。我们的方法可分为三个阶段。首先，基于固定的抖动下采样晶格对表示给定三维（3D）物体的数字全息图进行下采样。其次，通过像素复制将下采样后的全息图插值为可由低分辨率空间光调制器（SLM）显示的低分辨率全息图。第三，在SLM上叠加一个基于对全息图进行采样的相同抖动下采样晶格生成的光栅。光栅与低分辨率全息图的结合在很大程度上近似于原始全息图的分辨率。因此，我们提出的方法能够使用较低分辨率的SLM来显示数字全息图，为低成本全息视频显示的发展铺平了道路。
