Breaking diffraction limit of a small f-number compact camera using wavefront coding

Abstract

We propose a resolution enhancement method for mobile small f-number compact imaging systems based on wavefront coding and superresolution image processing. Wavefront coding increases the focus depth of an optical system and produces point spread functions (PSFs) with similar characteristics at different field and defocus positions. The designed target wavefront is realized as a combination of wavefront errors of each rotationally symmetric lens, without including an additional phase plate. Finally, using one deconvolution filter containing all the characteristics of the PSFs, we achieve high resolution, breaking the diffraction limit of small f-number and the resolution limit of the image sensor by super-resolution image processing.