OPTICAL FIBRE LASER DEVICE Russian patent published in 2020 - IPC G02B6/00 H01S3/67 

FIELD: optics.

SUBSTANCE: invention relates to laser fibre engineering. Fibre-optic laser device comprises a first fibre comprising a first fibre Bragg grating, a second fibre comprising a second fibre Bragg grating having a reflectivity which is lower than that of the first fibre Bragg grating, and a third fibre doped with a rare-earth element, the first end of which is connected to the first fibre, and the second end is connected to the second fibre. Central part of the core of the third fibre is more doped with a rare-earth element than the peripheral part of the core. In addition, the following expression is satisfied, in which Da is the diameter of the central part doped with the rare-earth element, and Db is the core diameter Db/2 ≤ Da ≤ (3⋅Db)/4.

EFFECT: technical result consists in enabling increase in the single-mode laser radiation efficiency.

3 cl, 22 dwg