Open AccessHigh-quality laser beam diagnostics using modified coherent phase modulation imaging
Author(s) -
Xiaoliang He,
Hua Tao,
Xingchen Pan,
Cheng Liu,
Jianqiang Zhu
Publication year - 2018
Publication title -
optics express
Language(s) - Uncategorized
Resource type - Journals
SCImago Journal Rank - 1.394
H-Index - 271
ISSN - 1094-4087
DOI - 10.1364/oe.26.006239
Subject(s) - optics , speckle pattern , modulation (music) , speckle noise , image quality , phase modulation , detector , laser , image resolution , noise (video) , phase retrieval , iterative reconstruction , beam (structure) , laser beam quality , computer science , physics , laser beams , phase noise , artificial intelligence , image (mathematics) , fourier transform , quantum mechanics , acoustics
Coherent modulation imaging (CMI) is a promising technique for online laser beam diagnostics; however, obvious speckle noise is always generated in the reconstruction, seriously degrading the spatial resolution and, accordingly, the accuracy. To solve this problem, both the optical setup of the common CMI and its reconstruction algorithm are slightly modified, and the performance of CMI in laser beam diagnostics can be obviously improved. By adding the second detector to record additional intensity distribution and using it to strengthen the intensity constraint of common CMI algorithm, the speckle noise in the reconstructed image can be distinctively reduced, and thus both the spatial resolution and the measurement accuracy are improved significantly. The feasibility of this proposed method is verified by proof-of-principle experiments.