Method and device of designing metasurface and storage medium

A device of designing a metasurface, comprising:

• a determination module, a simulation module and an optimization module;
• the determination module is configured to determine a phase distribution of an initial metasurface according to a preset image and a light source function of a first light source;
• the preset image represents a distribution schematic of speckles to be projected on a projection plane, and the preset image comprises a plurality of projection points in an array;
• a position of each projection point in the preset image is the same as a position of a center of each pattern projected on the projection plane;
• the first light source refers to a light source used in a design of the initial metasurface;
• the simulation module is configured to perform a simulation based on the phase distribution of the initial metasurface and a second light source, so as to obtain a speckle image;
• the second light source refers to a light source used in a measurement of the initial metasurface;
• the speckle image represents speckle patterns projected on the projection plane, obtained by passing light emitted by the second light source through the initial metasurface;
• the optimization module is configured to optimize the phase distribution of the initial metasurface through adjusting the projection points on the preset image if the speckle image does not meet a preset standard, so as to determine a target phase distribution;
• and the optimization module is also configured to generate the metasurface according to the target phase distribution.