论文标题
基于增强的Na菲涅尔全息图的广泛观看角度全息显示
Wide viewing-angle holographic display based on enhanced-NA Fresnel hologram
论文作者
论文摘要
全息图像的观察角扩大是实现全息显示的关键因素。已知数字全息图的数值孔径（Na）已知以确定图像的角场范围。在这里，我们通过数学上研究采样点扩散函数的内部结构，表明其调节曲线的自相似性，从而为视角对全息图数值光圈的依赖性提供了有效的基础。增强的Na菲涅尔全息图通过全息图像素倾斜以大于衍射角的视角重建图像，在该角度上，其角度值按整个全息图孔的NA表示，这是通过光学全息图成像系统地观察到的。最后，我们发现在增强的NA菲涅尔衍射状态下产生的溶副复制噪声通过数字化像素在衍射范围内有效抑制。这种特征使我们能够克服降低图像并去除高阶图像的干扰，从而导致广泛的观看角度全息显示。光学实验显示与数值模拟的结果一致。
The viewing-angle enlargement of a holographic image is a crucial factor for realizing the holographic display. The numerical aperture (NA) of digital hologram other than a pixel specification has been known to determine the angular field extent of image. Here, we provide a valid foundation for the dependence of viewing angle on the hologram numerical aperture by investigating mathematically the internal structure of the sampled point spread function showing a self-similarity of its modulating curves. The enhanced-NA Fresnel hologram reconstructs the images at a viewing angle larger than a diffraction angle by a hologram pixel pitch where its angle value is expressed in terms of the NA of whole hologram aperture, which is systematically observed by optical hologram imaging. Finally, we found that the aliased replica noises generated in the enhanced-NA Fresnel diffraction regime are effectively suppressed within the diffraction scope by a digitized pixel. This characteristic enables us to overcome the image reduction and to remove the interference of high-order images, which leads to the wide viewing-angle holographic display. Optical experiments are shown to be consistent with the results of numerical simulation.
