Abstract: A design method for a diffractive optical element for beam splitting, comprising: S11, determining an input light field distribution and a target output light field distribution of a diffractive optical element; S12, constructing a beam splitting lattice of the diffractive optical element, wherein the light splitting lattice is used for performing array replication on light sources to realize the speckle lattice in a specific field of view, and the arrangement mode of the beam splitting lattice is regular arrangement or longitudinal and/or transverse periodic staggered arrangement; S13, disturbing the beam splitting lattice to reduce a deviation between an actual output light field and the target output light field, and limiting the disturbance quantity to ensure that there is no obvious overlap or gap between adjacent blocks in the speckle lattice; and S14, designing the diffractive optical element according to the disturbed beam splitting lattice.

Abstract: A design method for a diffractive optical element for beam splitting, comprising: S11, determining an input light field distribution and a target output light field distribution of a diffractive optical element; S12, constructing a beam splitting lattice of the diffractive optical element, wherein the light splitting lattice is used for performing array replication on light sources to realize the speckle lattice in a specific field of view, and the arrangement mode of the beam splitting lattice is regular arrangement or longitudinal and/or transverse periodic staggered arrangement; S13, disturbing the beam splitting lattice to reduce a deviation between an actual output light field and the target output light field, and limiting the disturbance quantity to ensure that there is no obvious overlap or gap between adjacent blocks in the speckle lattice; and S14, designing the diffractive optical element according to the disturbed beam splitting lattice.

Abstract: A periodic optimization method for a diffractive optical element includes converting coordinates of individual target spots of a target spot array into angular spectrum coordinates, selecting an initial period, calculating diffraction orders of individual target spots, rounding the diffraction order, calculating the coordinates of actual projection spots by using the rounded diffraction orders, calculating evaluation indicator of period optimization, adjusting the period, and repeating the steps, and comparing the evaluation indicators to determine an optimal period for the diffractive optical element. With the periodic optimization method, an actual spot array is made to match a target spot array to the greatest possible extent with a small amount of calculations, thereby improving the design quality and accuracy of a diffractive optical element.

Abstract: A periodic optimization method for a diffractive optical element includes converting coordinates of individual target spots of a target spot array into angular spectrum coordinates, selecting an initial period, calculating diffraction orders of individual target spots, rounding the diffraction order, calculating the coordinates of actual projection spots by using the rounded diffraction orders, calculating evaluation indicator of period optimization, adjusting the period, and repeating the steps, and comparing the evaluation indicators to determine an optimal period for the diffractive optical element. With the periodic optimization method, an actual spot array is made to match a target spot array to the greatest possible extent with a small amount of calculations, thereby improving the design quality and accuracy of a diffractive optical element.

Abstract: A diffractive optical element (10) comprises a microstructure plane provided thereon with at least one microstructural pattern unit. The diffractive optical element (10) can receive a light beam emitted from a partitioned light source array (20) and project a light field on a target surface (OB), wherein the partitioned light source array (20) comprises a plurality of light source arrays (20-1, 20-2, ..., 20-n) spaced along a first direction, and the microstructural pattern unit is configured to be capable of diverging and light homogenization-modulating a light beam emitted from a light source in the plurality of light source arrays (20-1, 20-2, ..., 20-n) along the first direction such that light field regions projected by adjacent light source arrays (20-1, 20-2, ..., 20-n) on the target surface are adjoined or overlapped with each other in the first direction. In the embodiments of the invention, there are gaps between adjacent partitions. The light source partitions are lightened in turn.