Adaptive imaging system using image quality metric based on statistical analysis of speckle fields

This paper describes an Opto-Silicon Adaptive Imaging (OSAI) system capable of operating at low light intensities with high resolution, high accuracy, wide dynamic range, and high speed. The system consists of three major subsystems: (1) an adaptive imaging system in which a liquid crystal wavefront corrector measures image quality based on statistical analysis of a speckle field; (2) an image quality analyzer (IQA); (3) an opto-silicon multi-chip module combining a high-resolution ferroelectric liquid crystal SLM, CCD photodetector array, field-programmable gate array, and digital signal processor. The OSAI wavefront control applies adaptive optoelectronic feedback for iterative wavefront restoration and distortion compensation, suing an image quality metric based on statistical properties of the speckle field produced by moving a diffuser in the Fourier transform plane of a IQA optical system. A prototype IQA system was designed, manufactured, and tested using an input liquid crystal SLM, a Fourier lens, a light-shaping diffuser, and an output photodiode.

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