Study On The Imaging Theory Of The Optical Synthetic Aperture Imaging Systems

Optical synthetic aperture imaging technique is a new imaging technology toachieve higher spatial resolution of the optical system. It uses several of thesmall-aperture optical system to get the spatial resolution and image quality of asingle large-aperture optical system. This can solve the heavy weight, testingdifficulties and high cost problem of making a single large aperture system. Opticalsynthetic aperture system is a effective means to make large optical system. So it willpromote the optical space remote sensing technology and the further development ofastronomical optical technology.This dissertation derives and demonstrates the aperture optimization, aberrationanalysis, design method and three design examples. The main research contents are asfollows:1. The principle of the optical synthetic aperture system’s improvement in spatialresolution of the optical system is analyzed from space domain and frequency domain,and the system’s imaging model is designed in Matlab and ZEMAX software. Thetypical entrance aperture configurations of the optical synthetic system are analyzedby the imaging model. A new aperture configuration including9sub-apertures isgiven and analyzed in the dissertation.2. The aberration of the optical synthetic aperture is analyzed and its imagingmodel with aberration is designed. Aberration effect in two-aperture system isanalyzed by adding different aberration type and different aberration value to eachaperture. The phase diversity based on genetic algorithm is used to sense the measurethe wavefront error of the system. As an example, this method is used in athree-aperture system to measure the piston error of each aperture. The results showsthat the method is of high precision and stabilization.3. design method of two kinds of optical synthetic aperture system is analyzedand the design process of the multiple-telescope system is given. Three opticalsynthetic aperture systems are designed based on the design process. One is acatadioptric system and the rest are reflective system. The sub-telescope, beamcombiner and the system’s integration and optimization are described in detail. Spotdiagram, MTF and strehl ratio are used to evaluate the performance of the system.4. An experiment is carried out to validate the imaging principle of the optical synthetic aperture system. The effects of the fill factor and aperture configuration tothe system are analyzed. The experiment results and the theory simulation results areanalyzed, and the two results are consistent. This shows the theoretical analysis andsimulation are correct.