Mixed-order or fractional-order vortex beam modal identification device and method

Abstract

The invention discloses a mixed-order or fractional-order vortex light beam modal identification device and method. The device comprises a light beam generation device used for processing stray fundamental mode Gaussian light to generate Gaussian light in a horizontal polarization direction, and converting the Gaussian light into a horizontally-polarized mixed-order or fractional-order vortex light beam; a characteristic sample preparation device used for carrying out turbulence phase and two-dimensional fork-shaped vortex grating phase loading on the mixed-order or fractional-order vortex light beam, obtaining a far-field diffraction array after far-field diffraction, extracting a characteristic sample by utilizing a characteristic parameter extraction device, and obtaining a distortion characteristic sample required by full-connection neural network training and testing; anda network training and recognition device used for carrying out iterative training on the full-connection neural network through the distortion feature sample to obtain an optimal model, and then detecting the mixed-order or fractional-order vortex light mode in the test set through the optimal model. The invention aims to realize high-speed, high-precision and large-range vortex light mode detection, thereby improving the performance of OAM communication.

Description

technical field [0001] The invention relates to the fields of artificial intelligence and optical technology, in particular to a mixed-order or fractional-order vortex beam mode recognition device and method. Background technique [0002] Vortex light is a light beam carrying orbital angular momentum OAM (Orbital Angular Momentum, OAM, the angular momentum of moving in space). There is a phase singularity in the center of the beam, and it has a "doughnut" structure in the spatial distribution. These properties make vortex light widely used in optical manipulation, quantum information processing, photonic computer, and free-light space communication. In the field of communication, since different OAM beams are orthogonal to each other, a new physical dimension is provided, which can be combined with traditional multiplexing technology as a carrier for multiplexing, which greatly improves the communication capacity and spectrum efficiency of the system. At present, a lot of r...

AI Technical Summary

Problems solved by technology

However, shift keying and multiplexing communication, which manifest as fast switching of OAM modes, encounter great obstacles due to the lack of efficient and accurate identification of mixed-order or fractional-order vortex light.

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