Liquid crystal and metasurface combined continuous zooming super lens

Abstract

The invention relates to the field of imaging and optical information processing, and discloses a design scheme of a lens capable of continuously zooming from a visible light band to an infrared band.The design scheme comprises the steps of designing a superlens with a fixed focal length by utilizing excellent phase modulation capability of a metasurface; additionally arranging a layer of liquidcrystal and a composite layer below the super lens in a clinging manner; providing paraboloid-type voltage for the liquid crystal layer through the composite layer so as to generate paraboloid-type phase modulation in the liquid crystal layer, superposing the phase to the phase of the super lens to jointly determine the focal length of the lens, and changing paraboloid-type phase distribution in the liquid crystal layer by changing the voltage so as to achieve the zooming effect. The invention provides a method for continuously zooming a super lens by adopting a method of combining the super lens and liquid crystal. According to the method, only a single electrode is used on the premise of realizing continuous zooming, the processing complexity is reduced, the advantage of ultra-micro andultra-thin metasurface is maintained structurally, and the super lens is particularly suitable for a mobile phone lens.

Description

technical field [0001] The invention relates to the fields of imaging and optical information processing, in particular to a structural design of a continuously variable focus superlens combined with liquid crystals and metasurfaces. Background technique [0002] Metasurface is a planar structure that can effectively manipulate the wavefront. Its advantages are that it can be ultra-thin and precise in modulation. Since it was proposed, it has been used in the design and manufacture of various optical components, including lenses, wave sheets, polarizers, etc. However, so far, there are few reports about tunable metasurface devices. For the existing reports, the structure is slightly complicated and the effect is not ideal. This is due to the lack of effective modulation methods and precise processing techniques. [0003] Lenses are the simplest optical device, but also the most widely used and studied device, even so, the work on variable focus metalens is still very little...

AI Technical Summary

Problems solved by technology

At present, there is a zoom lens based on an elastic substrate, which can be continuously changed, but the structure is relatively complicated and requires a high voltage, which is very inconvenient in actual use and the focusing effect is not ideal.

The zoom lens based on the liquid crystal spatial light modulator is very complex in structure, requires a lot of electrodes, and because the pixel size is too large, there is multi-level diffraction, and the energy utilization rate is low

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