Ma Shitu, Lou Yimin, Hu Juanmei, Wu Fengmin
Appl Opt. 2020 Apr 1;59(10):3165-3173. doi: 10.1364/AO.385768.
A method to enhance the performance of an integral imaging system is demonstrated using the time-multiplexed convergent backlight technique. The backlight increases the space bandwidth of the integral imaging system. As a result, the resolution, depth of field, and viewing angle of the integral imaging system are increased simultaneously. The cross-talk noise is also decreased without using any optical barrier. One part of the added space bandwidth comes from the optimized illumination. The other part is converted from the time bandwidth of the system by time-multiplexing. The time-multiplexed convergent backlight modulates the direction of the backlight in time sequence to illuminate the elemental images. Then, the elemental images synthesize the 3D images using a microlens array. An elemental images rendering method using a conjugate pinhole camera and pinhole projector model is designed to dynamically match the illumination direction. The rendering method eliminates the distortion and maximizes the viewing angle and viewing zone. A field programmable gate array (FPGA)-based controller is used to manage and synchronize the time sequence of the backlight and the display devices. Using this technique, high-performance 3D images are realized. Comparison experiments of the integral imaging system using diffused backlight and convergent backlight are performed. The results show the effectiveness of the proposed technique.
利用时分复用会聚背光技术展示了一种提高积分成像系统性能的方法。该背光增加了积分成像系统的空间带宽。结果，积分成像系统的分辨率、景深和视角同时得到提高。在不使用任何光学屏障的情况下，串扰噪声也会降低。增加的空间带宽的一部分来自优化照明。另一部分通过时分复用从系统的时间带宽转换而来。时分复用会聚背光按时间顺序调制背光方向以照亮基元图像。然后，基元图像使用微透镜阵列合成3D图像。设计了一种使用共轭针孔相机和针孔投影仪模型的基元图像渲染方法，以动态匹配照明方向。该渲染方法消除了失真，并最大化了视角和视区。基于现场可编程门阵列（FPGA）的控制器用于管理和同步背光与显示设备的时间序列。利用该技术实现了高性能3D图像。对使用漫射背光和会聚背光的积分成像系统进行了对比实验。结果表明了所提技术的有效性。
