Deblur of radially variant blurred image for single lens system

Abstract

AbstractThis paper introduces a method to deblur a radially blurred image which is created by a single lens imaging system. Single lens imaging system does not create stronger lens aberrations around the center of an image, but stronger around the outside. One obvious phenomenon caused by this is the radially increased blurring effect along the radial line. Researchers have already studied one kind of radial blur caused by vertical motion between camera and object, but few have studied on the radial blur caused by inherent defect of a single lens system. Because of the radially variant property, a method is proposed in this paper that carries out the deconvolution using Polar coordinate system for both image and point spread functions (PSFs) converted from Cartesian coordinate system. By doing this the deblurring becomes a regular spatially invariant (SI) linear mathematical model for each circled region in the image that has same radial distance from the image center. Simulation results suggest the proposed method visually obtained the best deblurred image quality using four PSFs applied to four SI regions compared to deblurred images by other simulation conditions. However, segmenting the blurred image into more than four regions is undesirable because of the high β/n ratio. © 2010 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.