Electrically Control of Transverse Superresolution and Axial Focal Shift with Radial Birefringent Filter
电控径向滤波器的横向超分辨与轴向焦移

The electrically control of polarization-assisted transverse superresolution and axial focal shift utilizing electrically control radial birefringent pupil filter has been proposed in this paper. The structure of the filter consists of two parallel polarizers, an electrically controllable azimuth optical rotator including two quarter-wave plates and one liquid crystal or electro-optical variable wave plate and a symmetric birefringent element. Variation of light polarization caused by electro-optical effect provides the feasibility controlling the superresolution and focal capability. Polarization states transformation on the Poincar~ Sphere and Jones calculus for transmitted intensity are involved in this system. The most interesting and useful advantage of such a structure is that its transverse superresolution and axial focal shift quality can be changed merely controlling the applied-voltage on the electro-optical element. So no mechanic rotation is involved such as applied in the former design, and the vibration noise can also be avoided. Different structure parameters for obtained double effect such as azimuth angles of radial birefringent element and electro-optical modulation range are also given.