A high stability and high repetition rate mode-locked pulsed fiber laser

Abstract

The invention discloses a high-stability and high-repetition frequency mode-locking pulse fiber laser. The high-stability and high-repetition frequency mode-locking pulse fiber laser comprises a laser amplification device, a pulse narrowing device, a first circulator, a second circulator, a narrow-reflective spectrum fiber grating string, a fiber coupler and a single-mode fiber, wherein the laser amplification device is sequentially connected with the pulse narrowing device, the first circulator, the single-mode fiber, the fiber coupler and the second circulator through an optical fiber, the second circulator is connected to the laser amplification device again through an optical fiber, and the narrow-reflective spectrum fiber grating string is connected with the first circulator and the second circulator through optical fibers. The high-stability and high-repetition frequency mode-locking pulse fiber laser is of a full-fiber structure, and the laser is more compact and stable; the reflection wavelength distance and number of the optical grating are adjustable, and the high-stability and high-repetition frequency mode-locking pulse fiber laser is high in controllability; and by controlling the intervals between wavelengths of the optical grating string, the working wavelength and the pulse repetition frequency can be flexibly controlled, and extremely high pulse repetition frequency and narrow pulse width can be achieved.

Description

technical field [0001] The invention relates to a fiber laser, in particular to a high stability and high repetition frequency mode-locked pulse fiber laser. Background technique [0002] Due to its extremely narrow pulse width and extremely high peak power, the mode-locked pulse laser has strong applications in laser processing and metal surface plasma excitation, and the high-repetition mode-locked laser has great applications in the field of high-precision laser processing. big demand. Due to the limitation of cavity length, ultrashort pulse fiber lasers usually work at a low pulse repetition frequency (MHz level). The technical difficulty in realizing high repetition frequency ultrashort pulse fiber lasers lies in: how to use controllable spectral filtering methods, N stable longitudinal mode wavelengths with equal wavelength intervals are selected to participate in mode locking, so as to increase the pulse repetition rate. [0003] At present, many high-repetition-fre...

AI Technical Summary

Problems solved by technology

However, because the optical F-P filter has extremely high requirements on the flatness and parallelism of the reflective surface, it is difficult to realize, the stability is low, and it is difficult to control flexibly

[0004] Fiber Bragg grating devices can be used as narrow-bandwidth, low-loss filter elements, but since fiber Bragg gratings are usually reflective filter devices, it is difficult to ensure the corresponding multiple wavelengths when multiple fiber grating filters are introduced into the mode-locked fiber laser. The optical paths are equal, thus making mode locking difficult

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