Broadband angle selection laser filter

Abstract

The invention discloses a broadband angle selection laser filter, which comprises a first surface grating used for performing first diffraction on incident laser, and a Bragg grating for performing second diffraction on diffraction light transmitted from the surface grating, wherein the grating period of the surface grating is two times that of the Bragg grating. The broadband angle selection laser filter is fundamentally different from the traditional spatial filter which employs a lens and a pin hole, and the laser filter is compact in structure; the filter is wider in diffraction spectrum,has excellent low-pass filtering capacity on various spectral components, and can meet the requirement of short pulse and ultra-short pulse laser spatial filtering; and the bearable laser power is higher, and the possibility of causing a plugged hole effect and burning a filter component due to focused laser is eliminated.

Description

technical field [0001] The invention relates to the field of optical filtering, and more specifically relates to a broadband angle-selective laser filter with both angle-selective filtering capability and broadband output capability. Background technique [0002] High-power lasers are sensitive to various spatial disturbances, and the diffraction caused by various disturbances will reduce the spatial uniformity of the laser. Improving the near-field uniformity of the laser will help improve the load capacity of high-power laser devices. [0003] In high-power laser devices, spatial filters are essential key components. The traditional pinhole filter ("4f" system) is one of the most commonly used spatial filters. It first focuses the beam, uses the Fourier transform of the lens to separate the different spatial frequency components in the laser, the divergence angle of the high spatial frequency is large, and then uses the pinhole (or single-mode fiber) to select the require...

AI Technical Summary

Problems solved by technology

Spatial filters are mostly used in the field of information and communication. In the field of laser technology, most of the reported filters are narrow-band filters, while broadband spatial filters (supporting 100nm output bandwidth) that can be used in high-power pulsed laser systems have not yet been reported.

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