HIGH-ENERGY FIBER LASER, GENERATING SUPERSHORT PULSES Russian patent published in 2018 - IPC H01S3/67 

FIELD: optics.

SUBSTANCE: invention relates to laser equipment. Fiber laser that generates ultrashort pulses contains a fiber amplifier extended in free space and characterized by the presence of a multimode (MM) light-carrying alloyed core, which directs the pulses of the subnanosecond duration of a single-mode (SM) linearly polarized signal light beam in the direction of propagation. Also contains a pumping source, supplied with a fiber for delivering a pumping beam, which directs the pumping beam in the direction of propagation and is pulled out with the fiber amplifier in free space, and a portable laser head containing the ends of the fiber amplifier and the fiber delivering the pump light beam, respectively. In addition, the laser contains a flexible cable, which encloses the fiber amplifier together with the fiber of delivery of the pumping light beam and which is extended in free space. In this case, the portable laser head is configured to: redirect the pump light beam in the direction opposite to the propagation direction, so that the redirected pump beam hits the output end of the MM core; and issuing an amplified signal light beam in the propagation direction in almost single mode on the main mode. Linearly chirped fiber Bragg grating (FBG) is located in front of the fiber amplifier and is connected to it, while the FBG is based on a tunable pulse expander, which is intended to cause changes in the length of the FBG for the purpose of adjustable tuning of the pulse duration of the signal light beam in the required range of pulse duration.

EFFECT: technical result consists in providing the possibility of creating a high-energy compact fiber laser.

20 cl, 11 dwg