Open AccessDiffuser screen with flat-top angular distribution of scattered light realized by a dual-beam holographic speckle
Author(s) -
Chaoxiong Yang,
Hao Jiang,
Jinyu Wang,
Xiuhui Sun,
Yang Zheng,
Jianjun Chen,
Yongmo Lv,
Shi Yin
Publication year - 2021
Publication title -
optics express
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.394
H-Index - 271
ISSN - 1094-4087
DOI - 10.1364/oe.420910
Subject(s) - optics , speckle pattern , holography , physics , brightness , diffuser (optics) , scattering , beam splitter , laser , light source
Holographic speckle screens with the Gaussian type distribution of scattered light, which are used to increase the viewing angle of the image in projection display systems, result in nonuniform image brightness in different observing positions. In this study, based on Helmholtz-Kirchhoff theory, a dual-beam scattering theory of rough surface is derived. By analyzing the spatial frequency spectrum of the scattered light, it is found that when two laser beams irradiated the ground glass at a certain angle, the resulting speckles recorded on the photoresist can generate a flat-top angular distribution of the scattered light. Speckle screens are fabricated by two light beams at different angles, and the angular intensity distribution of scattered light is measured. The results are in good agreement with the theory. Compared with the Gaussian type diffuser, the energy efficiency of the speckle screen proposed has a 46% increase when the angular luminance uniformity is set to be 80%, which effectively improves the brightness when used in a head up display system.