关键词: 自适应光学, 数字全息, 形位误差校正, 分布式成像, 投影变换, 菲涅尔衍射

Abstract: Distributed holographic aperture digital imaging technology is an active imaging technology which uses digital holographic technology to record sub-aperture complex amplitude information, and then realizes comprehensive imaging through complex amplitude stitching between apertures. In engineering applications, it is well known that the assembly error of the imaging system will cause the shape and position errors between the sub-aperture complex amplitudes, and then blur the image after aperture synthesis. While in the existing methods, the shape and position errors are mostly corrected by the similar transformation model, but the relationship between the complex amplitude and ideal complex amplitude is complex projection transformation, so the method based on the similar transformation model is no longer applicable. Firstly, a method for correcting the shape and position errors between complex amplitudes on the image plane is proposed. In this method, projection transformation correction on the image plane complex amplitude is performed firstly through image registration, and then inverse Fresnel diffraction is performed on the corrected image plane complex amplitude to obtain the complex amplitude of the pupil plane corrected for shape and position errors. Then a distributed holographic aperture imaging system is built, and the shape and position errors are effectively corrected by correcting the shape and position errors between complex amplitudes on the image plane as suggested in this work.

Key words: adaptive optics, digital holography, shape and position error correction, distributed imaging; projection transformation, Fresnel diffraction