Liu Boyang, Sang Xinzhu, Yu Xunbo, Ye Xiaoqian, Gao Xin, Liu Li, Gao Chao, Wang Peiren, Xie Xinhui, Yan Binbin
Opt Express. 2021 Mar 1;29(5):7435-7452. doi: 10.1364/OE.418132.
Time-multiplexed light-field displays (TMLFDs) can provide natural and realistic three-dimensional (3D) performance with a wide 120° viewing angle, which provides broad potential applications in 3D electronic sand table (EST) technology. However, current TMLFDs suffer from severe crosstalk, which can lead to image aliasing and the distortion of the depth information. In this paper, the mechanisms underlying the emergence of crosstalk in TMLFD systems are identified and analyzed. The results indicate that the specific structure of the slanted lenticular lens array (LLA) and the non-uniformity of the emergent light distribution in the lens elements are the two main factors responsible for the crosstalk. In order to produce clear depth perception and improve the image quality, a novel ladder-type LCD sub-pixel arrangement and a compound lens with three aspheric surfaces are proposed and introduced into a TMLFD to respectively reduce the two types of crosstalk. Crosstalk simulation experiments demonstrate the validity of the proposed methods. Structural similarity (SSIM) simulation experiments and light-field reconstruction experiments also indicate that aliasing is effectively reduced and the depth quality is significantly improved over the entire viewing range. In addition, a tabletop 3D EST based on the proposed TMLFD is presented. The proposed approaches to crosstalk reduction are also compatible with other lenticular lens-based 3D displays.
时分复用光场显示器(TMLFDs)能够在120°宽视角下提供自然逼真的三维(3D)性能,这在3D电子沙盘(EST)技术中具有广泛的潜在应用。然而,当前的TMLFDs存在严重的串扰问题,这可能导致图像混叠和深度信息失真。本文对TMLFD系统中串扰产生的机制进行了识别和分析。结果表明,倾斜柱面透镜阵列(LLA)的特定结构以及透镜元件中出射光分布的不均匀性是导致串扰的两个主要因素。为了产生清晰的深度感知并提高图像质量,提出了一种新颖的梯形液晶显示子像素排列方式,并将一种具有三个非球面表面的复合透镜引入到TMLFD中,以分别减少这两种类型的串扰。串扰模拟实验证明了所提方法的有效性。结构相似性(SSIM)模拟实验和光场重建实验也表明,在整个视角范围内,混叠得到有效减少,深度质量显著提高。此外,还展示了基于所提TMLFD的桌面3D EST。所提出的减少串扰的方法也与其他基于柱面透镜的3D显示器兼容。