A Wavefront Detection Method Based on Nonlinear Interface Cerenkov Frequency Multiplication

Abstract

The invention relates to a wavefront detection method based on nonlinear interface Cherenkov frequency doubling, and belongs to the technical field of wavefront detection based on nonlinear optics. According to the material of a nonlinear interface, the incident angle of fundamental-frequency light to be detected is adjusted to guarantee that the fundamental-frequency light enters the nonlinear interface to generate nonlinear Cherenkov frequency-doubled light, and the wavefront distribution of the frequency-doubled light is received and reconstructed to deduce the wavefront distribution of thefundamental-frequency light. In the method, the phase matching relationship can be automatically met in a broad frequency spectrum based on nonlinear interface Cherenkov frequency doubling, and broadband frequency conversion is realized; meanwhile, the frequency-doubled light is automatically separated from the fundamental-frequency light, no filtering processing is needed, the light path is simplified, and measurement is facilitated; besides, the wavefront distribution relationship correspondence of the frequency-doubled light and the fundamental-frequency light is simple, and wavefront reconstruction of the fundamental-frequency light can be directly performed easily.

Description

technical field [0001] The invention belongs to the technical field of wavefront detection based on nonlinear optics, and in particular relates to a wavefront detection method based on nonlinear interface Cerenkov frequency doubling. Background technique [0002] During the propagation of light, its wavefront (phase) can carry a variety of physical information, such as atmospheric turbulence, surface error of optical components, aberration of optical imaging system, phase characteristics of biological structures, etc. Therefore, wavefront detection technology has a wide range of applications in astronomical observation, optical component surface shape detection, biomedical imaging and other fields, and has also played an important role in some frontier fields, such as quantum coherence detection, precision onlooker control, material detection, etc. . For the measurement of the time-domain distribution information of the wavefront, the most common methods are the frequency-r...

AI Technical Summary

Problems solved by technology

However, if the general collinear frequency doubling process is adopted, the following problems exist: only under the condition of strict phase matching, the wavefronts of the fundamental frequency light and the frequency doubling light will be consistent, and the common walk-off effect, beam Practical issues such as divergence and spectral width can cause phase mismatch

Therefore, the idea of ​​this wavefront detection is very limited, and it is difficult to measure directly, so researchers need to make new improvements

For example, the phase mismatch is obtained from the spectral intensity of the doubled frequency light and the spectral intensity of the fundamental frequency light, and then the wavefront distortion of the fundamental frequency light is obtained through the relationship between the phase mismatch and the propagation angle. However, these improvements make the measurement method or restoration algorithm become more complex

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