关键词: 光参量放大/
光学增益/
外接圆模型/
峰值信噪比
English Abstract
Sensitive detection of ultra-weak infrared image using parametric frequency up-conversion and amplification
Zhang Teng-Fei1 2,Yang Jing1,
Hou Yan-Xue2,
Wang Wei-Wei1,
Zhao Wei1,
Zhang Jing-Yuan1,
Cui Da-Fu1,
Peng Qin-Jun1,
Xu Zu-Yan1
1.Research Center for Laser Physics and Technology, Key Lab of Functional Crystal and Laser Technology, Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, Beijing 100190, China;
2.College of Science, Yanshan University, Qinhuangdao 066004, China
Fund Project:Project supported by the Young Instructor Self-Topic Research Program of Yanshan University, China (Grant No. 13LGB031).Received Date:24 July 2015
Accepted Date:27 August 2015
Published Online:05 January 2016
Abstract:Optical parametric frequency up-conversion and amplification, used for ultra-weak infrared image detection, is investigated both numerically and experimentally. A circum-circle model of spatial filtering is proposed to suppress the parametric fluorescence background noise. Combining the spatial filter, image relay module and band-pass filter, the fluorescence noise is suppressed by 70%. Accordingly, the image quality is significantly improved and the peak signal-to-noise ratio is increased by 22%. Based on the 10 Hz, mJ-level, 355 nm picosecond pump laser, the weak infrared image is amplified and up-converted into the visible region, and over 1.3108 (82 dB) optical gain is obtained at the same time. Our experiment demonstrates that the detection sensitivity of the conventional uncooled CCD can be as high as 7.4 photons per pixel when the high gain OPA is used as an image preamplifier. The scheme in this paper is expected to be used in single-photon-level sensitive infrared imaging.
Keywords: optical parametric amplification/
optical gain/
circum-circle model/
peak signal-to-noise ratio
