The Design Of Electronically Controlled Tunable Superresolution Pupil Filter

Super-resolution technology , based on the requirement beyond the classical diffraction limit, is a technology that can attain the distribution of the three-dimension spatial intensity. At present, the super-resolution technology is already widely used in optical storage, optical communication, optical imaging, the modern optical systems design, ultra-large scale integrated circuit production and other fields. The main way to obtain super-resolution is the design of pupil filter to achieve the re-distribution of the filtered three-dimensional light field near the focus.Based on space-variant polarization manipulation and polarizing interference, combined with electro-optical modulation techniques, two kinds of electric tunable super-resolution optical pupil filter is presented in this paper.(1) Composite delayer-type electric control pupil filters: a two-zone composite delayer as the core, and electro-optical crystal, polariscope (crystal type), consisting of a full crystal-based pupil filter. The combination of composite wave plate and electro-optical crystal can achieve to control the difference of phase delay between the two zones through the voltage. The results show: This pupil filter can not only improve the super-resolution capabilities in the transverse, but also by adjusting the electro-optical phase delay and the right azimuth angle in two zones to achieve real-time control of axial focal shift or achieve focal depth on axial direction.(2) Composite electro-optic crystal-based electric control pupil filters: the two zones of composite electro-optic crystal as the core, andλ/ 4 retarder, polariscope (crystal type) combined to form another full crystal-based pupil filter. Compared with the former pupil filter, the space-variant polarization manipulation is different, from the homogeneous electro-optical phase-delay into the non-homogeneous electro-optical phase-delay between the two zones. The results show: This pupil filter can not only achieve the real-time control of the super-resolution capabilities by the voltage in transverse, but also can achieve the real-time control of axial shift by the voltage and achieve large axial focal depth on axial direction.