超短脉冲激光电子学全息选通透过散射介质成象系统的噪音分析

本文详细分析了超短脉冲激光电子学全息选通透过散射介质成象系统的噪音因素,其噪音来源主要有电子学全息图的记录过程、再现过程以及CCD自身的噪音、系统光学元件产生的噪音等等,提出了相应的噪音处理措施.

NOISE ANALYSIS FOR THE IMAGING SYSTEM THROUGH SCATTERING MEDIUM USING ULTRASHORT PULSE LASER ELECTRONIC HOLOGRAPHY

In this article,noises of the imaging system through scattering medium using ultrashort pulse-laser electronic holography is analyzed in detail.The main noise sources are the recording and reconstructing processes of electronic holograms,and the noise of CCD camera and optical system components.In the recording process,there are white noise produced from later-arriving-light and noise from the shoulder of fs laser-pulse,multiple reflections of reference light,unstable optical system and scattering medium.Besides,if the fringes of holograms are not straight and vertical,or the angle between object and reference light is too small,it is possible that noise is produced.In reconstructing process,the overlap between +1 order and 0 order of spatialfrequency spectrum of holograms is a main reason for noise.CCD camera noise includes thermal noise,shot noise,sensitivity variation, sampling error etc.Also dust and the defect of optical system components can produce noise.The relevant processing measures of all noises are put forward.