| Traditional optical components use different thicknesses of the lens surface.When the light beam passes through the lens,the optical path difference is generated,so as to realize the control of the phase.Therefore,traditional optical components have large volume and weight,low design freedom,and curved contours,which are not conducive to the development of miniaturization and integration of modern optical systems.With the development of micro-nanofabrication technology,the use of metasurface unit structure to achieve precise control of phase has become popular in research fields.Metasurface refers to an artificial layered material with its thickness less than the wavelength,which combines the emerging technologies of optics and nanotechnology based on the interaction of light and matter,and can effectively control the wave amplitude,phase,polarization,propagation mode and other characteristics of electromagnetic.With the introduction to the concept of metasurface,domestic and foreign researchers have conducted extensive and in-depth research on it.At present,the research on metasurfaces has been extended to near-infrared and even visible light bands.It not only provides a huge breakthrough to the electromagnetic properties of traditional materials,but also overcomes the difficulty of processing the three-dimensional structure of metamaterials with two-dimensional planar structures,providing a theoretical basis for the miniaturization and integration of optical devices.Metalens constructed from micro-nano structure arrays are small in size and light in weight,and can be functionally expanded through composite structure design,which is one of the cuttingedge technologies in the current optical imaging field.The diameter of metalens reported so far is generally in the micro-nano scale.For metalens with a centimeter-scale diameter,the number of micro-nano structural units can reach billions.If these massive micro-nano structures are drawn one by one,the layout file will be too large,so that the drawing time will be long and the layout can not be opened.In order to solve this problem,based on the layout design software LEdit,this paper proposed a ring layout design method for metalens,and used a combination of binary and library calls to draw the metalens to construct a cell array in each ring.In this way,the effective compression of the layout file of the large-aperture metalens is realized.The research results showed that the designed metalens can achieve subwavelength focusing.On the other hand,for a metalens with a diameter of 50 mm,using the layout drawing method proposed in this paper,the layout file size is 176 MB,which is much smaller than the layout file size（3.70 TB）generated by the one-by-one modeling and drawing method.For a metalens with a diameter of120 mm,using this method,the size of the layout file is only 452 MB.This paper realizes the efficient compression of massive data of large-aperture metalens layout design files,thus ensuring the manufacturability of large-aperture metalens design.Finally,a systematic study of the tolerance characteristics of metalens focusing performance is carried out.The effects of the incident light error and the shape and parameter errors of the metalens building unit on the focusing performance of the metalens were mainly analyzed.The research results determine the range of the wavelength error of incident light,the angle error of incident light,the parameter error of the building unit and the shape error of the building unit.The designed metalens are manufacturable on the premise of ensuring good focusing properties. |
