Dielectric metasurface-based polarization generator and design method thereof

Abstract

The invention provides a polarization generator based on a medium metasurface and a design method thereof. The designed polarization generator is integrated by three groups of double-vibration-state focusing metasurfaces; According to parabolic phase distribution, an x-line polarization component and a y-line polarization component of incident light, a 45-degree linear polarization component and a135-degree linear polarization component, and a left-hand circular polarization component and a right-hand circular polarization component are extracted and focused to six different positions of a transmission surface respectively. The transmission type metasurface is composed of a two-layer structure, a substrate and a rectangular column array with the sub-wavelength thickness. The transmissiontype resonance unit of the transmission type metasurface is composed of a rectangular nano antenna, and phase response to different polarization states is achieved by changing the length, the width and the rotation angle of an optical axis through a double-phase modulation method. According to the design method, for different incident wave lengths, high-transparency materials of corresponding wavebands can be selected to design the metasurface, so that the design method has very high flexibility, is simple in structural design and convenient to process, and has a wide application prospect.

Description

technical field [0001] The invention belongs to the technical field of integrated optical device design based on artificial composite material metasurface, and specifically relates to a medium-based metasurface plane lens and a dual-phase control method. Background technique [0002] The generation and processing of polarized light has traditionally utilized a series of well-arranged polarizers, such as polarimeters and waveplates, placed in succession along the optical path in front of the detector. Traditional discrete optical components are bulky, complex to measure, and costly, and cannot meet today's requirements for the integration of optical devices. The creation of artificial surface nanostructures—optical metasurfaces—has attracted a lot of attention due to their simplification in optical manipulation and the development of fabrication techniques. Metasurface has the characteristics of ultra-thin and miniature, which solves the disadvantages caused by the volume pr...

AI Technical Summary

Problems solved by technology

Most of these devices are used to generate linearly polarized light, and while the desired polarization state is obtained, other polarization states are directly filtered out, the corresponding energy is lost, and the transmitted brightness is also reduced.

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