Diffraction simulation method for generating hollow beam

Abstract

The invention discloses a diffraction simulation method for generating a hollow beam, and the method comprises the steps: obtaining light parameters of a to-be-simulated Gaussian beam at different positions after the to-be-simulated Gaussian beam passes through a spiral phase plate, and calculating a corresponding to-be-simulated phase difference based on the light parameters; based on the to-be-simulated phase difference, calculating the topological charge of the corresponding vortex beam; obtaining the ring number of the Fresnel zone plate to be simulated as the ring number to be simulated, and calculating the ring radius corresponding to the ring number to be simulated; calculating the light spot intensity of the Gaussian beam to be simulated on the focal plane based on the radius of the ring number to be simulated and the topological charge number of the vortex beam; simulating the to-be-simulated Gaussian beam based on the light spot intensity and the radius of the to-be-simulated ring number, obtaining a diffraction simulation light spot, it can be seen through the diffraction simulation light spot that the method converts the incident beam into the hollow beam, so that energy loss caused by center shielding of the Cassegrain antenna is avoided.

Description

technical field [0001] The invention belongs to the technical field of diffractive optical device design, and in particular relates to a diffraction simulation method for generating a hollow beam. Background technique [0002] Inter-satellite laser communication usually uses the Cassegrain optical antenna as the transmitting antenna. The Gaussian beam emitted by the laser is pre-collimated and the parallel beam of the beam expander enters the Cassegrain optical antenna. After being focused, it is reflected by the hyperboloid secondary mirror for the first time, and then it is reflected by the parabolic primary mirror for the second time and then emitted with a very small divergence angle. However, due to the occlusion of the secondary mirror of the antenna, part of the beam at the center of the Gaussian beam cannot be emitted. The energy at the center of the Gaussian beam accounts for the largest proportion, and if it cannot be launched, it will cause a huge loss of beam en...

AI Technical Summary

Problems solved by technology

[0003] The technical problem to be solved by the present invention is that when the Gaussian beam is incident on the Cassegrain optical antenna, due to the center blocking, the energy in the center of the beam cannot be transmitted through the antenna, resulting in a huge loss of beam energy

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