A STUDY ON REAL-TIME LOW-FREQUENCY SPATIAL FILTERING PROCESS OF AN OPTICAL IMAGE USING LiNbO3:Fe CRYSTAL
LIU SI-MIN (刘思敏), LU YI (陆猗)a, CHEN HAI-DONG (陈海东), LIU JUN-MIN (刘军民), XU JING-JUN (许京军), ZHANG GUANG-YIN (张光寅), YANG LI-SEN (杨立森)b, MEN LI-QIU (门丽秋), SUN QIAN (孙骞)
Department of Physics, Nankai University, Tianjin 300071, China; a Department of Physics, Branch College of Tianjin University, Tianjin 300193, China; b Department of Physics, Neimenggu Normal University, Huhhot 010020, China
Abstract The optimum image processing result of low-frequency filtering was obtained when LiNbO3:Fe crystal as a spatial filter was placed at a certain position behind the spatial-frequency spectral plane of an optical Fourier transform system, which corresponds to the minimum transmittance ratio in Z-scan curve. The experimental results show that self-defocusing due to photorefractive negative-lens effect is the main factor responsible for the low- frequency filtering.
Received: 02 September 1992
Revised: 30 August 1993
Accepted manuscript online:
(Other nonlinear optical materials; photorefractive and semiconductor materials)
Fund: Project supported by the National Natural Science Foundation of China and by the State Science and Technology Commission of China, through a grant for key research project in climbing program.
Cite this article:
LIU SI-MIN (刘思敏), LU YI (陆猗), CHEN HAI-DONG (陈海东), LIU JUN-MIN (刘军民), XU JING-JUN (许京军), ZHANG GUANG-YIN (张光寅), YANG LI-SEN (杨立森), MEN LI-QIU (门丽秋), SUN QIAN (孙骞) A STUDY ON REAL-TIME LOW-FREQUENCY SPATIAL FILTERING PROCESS OF AN OPTICAL IMAGE USING LiNbO3:Fe CRYSTAL 1994 Acta Physica Sinica (Overseas Edition) 3 506
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