Design and fabrication of circularly polarized light metalens

Circularly polarized light is polarization-preserving and sensitive to special substances and has great application potential in cloud removal and target recognition. Traditional circularly polarized light imaging equipment requires a variety of optical devices such as a linear polarizer, wave plate, and focusing lens, which increases the complexity of the system and affects the volume and weight of the system. In this paper, we present a compact circularly polarized light camera, which realizes the extraction and focusing of circularly polarized light by using multifunctional planar metalens. The design material of the metalens is amorphous silicon, with an operating wavelength of 800 nm, a diameter of 2 mm, and a focal length of 20 mm. The test results show that the circularly polarized light camera has a good imaging effect and meets the design requirements. This paper explores the further application of metalens and promotes the wide application of polarizing imaging in machine vision, remote sensing, and other fields.