| CPC G02B 27/0012 (2013.01) [G02B 27/0944 (2013.01)] | 20 Claims |

|
1. A design method of a diffractive optical element, characterized by comprising:
S101: determining a parameter of a light source and a target light field of the diffractive optical element;
S102: determining a distribution of a plurality of first microstructure pattern units on the diffractive optical element based on the parameter of the light source, wherein the parameter of the light source comprises a width along a first direction and a length along a second direction of each light source array of the light source, and a number of light source arrays of the light source;
S103: dividing the target light field into a plurality of target maps, a superimposition of the plurality of target maps forming the target light field, and each of the first microstructure pattern units corresponding to one of the target maps;
S104: performing distortion pre-correction on the plurality of target maps respectively, wherein the distortion comprises pincushion distortion; and
S105: designing corresponding phase distributions of the plurality of first microstructure pattern units respectively, based on the plurality of corrected target maps and the parameter of the light source, wherein the parameter of the light source further comprises a distance between the target light field and the light source, and a field of view of projection,
wherein the diffractive optical element further comprises a plurality of second microstructure pattern units arranged at a periphery of the plurality of first microstructure pattern units, such that all of an incident light spot from the light source is irradiated on the diffractive optical element, wherein the plurality of first microstructure pattern units is taken as a main region, and the plurality of second microstructure pattern units is taken as an anti-leakage region to prevent light leakage that occurs when the incident light spot is irradiated on first microstructure subunits at an edge of the main region.
|