Wide-incident angle and low polarization aberration edge filter

Nowadays, optical elements are often shared in order to improve compactness of optical system and edge filter is one of the core parts. For same spectral system, when half convergence light incidents on edge filter, Sagittal and meridian will have different incident angle range, which cause different polarization characterization for the two directions and is harmful to the optical system’ MTF. In order to improve image quality, all factors affecting MTF are analyzed. When light incidents on edge filter, the difference between P and S polarization’s reflection phase can cause MTF drop. The design process of edge filter is optimized. Optical spectrum and reflection phase are optimized together. The variation is kept in a certain range for reflection phase of P and S polarization when edge filer attains spectrum requirement. The newly designed edge filter is sticked to optical system and carried out simulation. The calculation results showed that the newly designed edge filter has little effect on MTF. Ion-assisted e-beam evaporation method is used to deposit edge filter multilayer and the measurement result is in good accordance with that of the design. We think that a new design method is raised for design wide-incident angle and low polarization aberration edge filter.