Author(s):
Quan, Jiale; Yan, Binbin; Sang, Xinzhu; Zhong, Chongli; Li, Hui; Qin, Xiujuan; Xiao, Rui; Sun, Zhi; Dong, Yu & Zhang, Huming
Abstract:
“In this paper, we propose a method to generate multi-depth phase-only holograms using
stochastic gradient descent (SGD) algorithm with weighted complex loss function and masked multi-
layer diffraction. The 3D scene can be represented by a combination of layers in different depths. In
the wave propagation procedure of multiple layers in different depths, the complex amplitude of
layers in different depths will gradually diffuse and produce occlusion at another layer. To solve this
occlusion problem, a mask is used in the process of layers diffracting. Whether it is forward wave
propagation or backward wave propagation of layers, the mask can reduce the occlusion problem
between different layers. Otherwise, weighted complex loss function is implemented in the gradient
descent optimization process, which analyzes the real part, the imaginary part, and the amplitude
part of the focus region between the reconstructed images of the hologram and the target images. The
weight parameter is used to adjust the ratio of the amplitude loss of the focus region in the whole
loss function. The weight amplitude loss part in weighted complex loss function can decrease the
interference of the focus region from the defocus region. The simulations and experiments have
validated the effectiveness of the proposed method.”
Issue/Year: Micromachines, Volume 14; Number 3; Pages 605; 2023
DOI: 10.3390/mi14030605