Precise analysis of combination homogeneous-inhomogeneous-material superresolution filters with double-tunable modes

By using a Jones matrix, the precise expression for the pupil function of a two-adjustable-mode superresolving filter, a combination of a radial birefringent plate and a glass annular plate, is obtained. This filter can provide superresolution in both radial and axial adjustment operations, which can supplement each other in setting accuracy and superresolution range in practical use. As an adjustable filter, it is less dependent on wavelength. With the relative radius of the inner plate set to be epsilon=0.52 and the rotating angle set to be 45 degrees , this type of filter can achieve better superresolution performance than the continuous-phase filters reported in Opt. Lett.28, 607 (2003).