Metasurface-based polarization color routers

Abstract

Polarization, an attribute of light, carries a lot of vital information independent of intensity and color content. Polarization imaging is very useful in applications including diffuse/specular component separation, material classification and reflectance estimation. Color routers applied in color imaging provide an efficient way to sort and guide different color lights to the corresponding output ports. Here, we report the design and experimental realization of a compact metasurface-based polarization color router. This color router shows a micron Bayer pattern (RGGB distribution) under the illumination of white light with any polarization. In addition, the green light intensity at the corresponding pixel changes regularly depending on the polarization light, illustrating the polarization color router can act as a polarizer at the same time. The measured light utilization efficiency of the polarization color router reaches a value of 88%. A correlation coefficient of 0.98, which is defined as the fitting effect between the measured and theoretical illuminating light polarization angles, was achieved. This device possesses the advantages of a lightweight, high light utilization efficiency and polarization-integrated detection functions, which could provide a new way for its applications in integrated CMOS image sensors.