Multi-Wavelength Multifocal Metasurface with Polarization Multiplexing

A polarization multiplexed metasurface is designed to focus red, green and blue light. This metasurface adjusts the rotation angle of titanium dioxide nano-pillars to achieve the modulation of incident light based on the geometric phase principle. The high polarization conversion efficiency can be achieved by only three different nanopillar sizes. This metasurface can focus three-color light on the different positions of the same focal plane and thus to realize the control of focus position based on the polarization response characteristics. The metasurface device designed here can be used as a compact optical device in the fields of portable imaging systems, polarized devices, encrypted information transmission, and so on.