Method of Directly Writing MPA on Photosensitive Surface of Detector Based on FIB.

The division of focal plane (DoFP) polarization detector has great potential for the development of aerospace polarimeters, but the existing commercial DoFP polarization detector cannot satisfy all the missions due to the diversity of satellite payloads. Here, we propose a method of directly writing a micro-polarizer array (MPA) on the detector surface based on focused ion beams (FIB) and fabricating a push-broom scanning DoFP polarization detector. The feasibility and low crosstalk of the solution were proved through testing, and the reasons for the low extinction ratio caused by oxidation were explained through characterization and numerical calculations. This scheme is not only applicable to DoFP polarization detectors but also provides ideas for the integration of other metasurface structures and detectors.

Numerical study of a high-extinction-ratio micro-polarizer array with a metal grid substrate.

In this paper, a complete investigation and simulation of the extinction ratio (ER) in a setup with a micro-polarizer array (MPA) is performed. A metal grid substrate structure, which can effectively reduce optical crosstalk and improve the ER, is proposed. The numerical calculation results show that the ER of our proposed structure is more than 10-fold higher than that of the traditional structure. Moreover, the effect of its structural parameters to the ER has been researched, and the results showed that when the substrate is thicker, the incident angle of light is less than 15°, the metal width is larger than 900 nm, and a complete grating with more than 20 periods on a single pixel can obtain a high ER.