Scattering surface design method and scattering surface design apparatus

A scattering surface design apparatus for designing a scattering surface including unit scattering cells arranged on a substrate, the scattering surface design apparatus comprising:

• a memory storing a design method program for designing a scattering surface;
• and
• a processor configured to perform the design method program for designing the scattering surface,
• wherein the processor is configured to design a scattering surface on which super cells, each of which includes a plurality of unit cells, are regularly arranged, and
• wherein the processor is configured to perform:
• a step of setting a plurality of scattering surfaces defined with a parameter corresponding to beams formed by the super cells;
• a cost function evaluation step for the scattering surfaces;
• a genetic change step of changing the parameter using a genetic algorithm;
• a scattering characteristic evaluation step of computing a cost function from the parameter changed according to the genetic algorithm to evaluate a scattering characteristic;
• and
• a step of performing the genetic change step and the scattering characteristic evaluation step until an end condition for a targeting scattering characteristic is met.