Q-SWITCHED ALL-FIBER LASER

摘要

A Q-switched all-fiber laser has a long period fiber grating (LPFG) switch with optical spectral characteristics that are controlled by application of stress. An actuator applies stress to selected sections of the LPFG in order to switch a fiber laser cavity at a specified wavelength. A controller controls the application of stress in the time domain, thereby switching the Q-factor of the fiber laser cavity.

主权项

1. A fiber laser apparatus configured to generate Q switched optical pulses, comprising:
a first fiber Bragg grating having a first reflective center wavelength; a second fiber Bragg grating having a second reflective center wavelength, the second reflective center wavelength being in a reflective wavelength bandwidth of the first fiber Bragg grating, the first and second fiber Bragg gratings configured to provide optical feedback for laser oscillation and to confine laser oscillation wavelength; at least one long period fiber grating disposed between the first fiber Bragg grating and the second fiber Bragg grating, the long period fiber grating having a switching wavelength in which switching wavelength bandwidth fully covers the wavelength bandwidth of the first fiber Bragg grating and the second fiber Bragg grating; a gain fiber disposed between the first fiber Bragg grating and the second fiber Bragg grating, the gain fiber configured to provide optical gain; and at least one actuator configured to apply stress to the long period fiber grating to cause switching of Q factor of the laser cavity and generation of Q switched optical pulses.