Focusing light based on phase-controlled metasurface

Volume holograms can achieve concentration of sunlight, but it has shortcomings such as small concentration angle, dispersion, and complex production process of the volume holography material, which is difficult to mass produce. This paper proposes a method based on the metasurface concentrating sunlight. We analyzed the mechanism of volume holographic light focusing by Kogelnik coupling wave theory, which is greatly limited by wavelength selectivity. Utilizing the metasurface control mechanism on the wave front phase, the array arrangement that meets the light concentrating effect was designed. Simulation analysis shows that the metasurface can achieve light concentration in the visible light band with low dispersion.