Inverse problem on Imaging and Imaging System

Abstract

In this thesis we try to provide novel solutions to key problems related to imaging and imaging system. Imaging is usually referred to as the technique for reproducing the information of the object. In optics, we usually refer the object information to the light field in the object plane due to the interaction of the illumination field and the object. Imaging technique allows the reproduced object information to be recorded by detectors such as human eye, photo resist, or CCD/CMOS sensor. In order to image an object, there must be light. We consider only un polarized quasi-monochromatic light illuminating the object and we approximate the field in the object plane by the multiplication of the transmittance / reflectance of the object and the illumination field (the first Born approximation). However, the results in this thesis can also be generalized to situations beyond the above scope. Here we mainly focus on two aspects: the aberrations, the errors of the imaging system, and the spatial coherence of the light field. In a typical imaging scenario, we consider the object plane field as a source consisting a series of point sources. The field generated by each point source propagates independently to the image plane through the imaging system. Ideally, these fields should all identically have the correct distribution and be centered at the correct location. However, this is not the case in presence of the aberrations. As a result, the image will become blurred.