Patent ID: 9653872
Date: 2017-05-16
CPC Classifications: G02F,H01S

Claim:
1. A method comprising: providing a rare-earth doped first fiber gain medium; configuring a ring optical signal path that extends through the first fiber gain medium; Q-switching a ring signal laser beam in the ring optical signal path, wherein the Q-switched ring signal laser beam has a pulse repetition rate that is independent of the ring optical signal path's length during normal operation of the Q-switching, and wherein the Q-switched ring signal laser beam has a first wavelength and propagates in the ring optical signal path in a first direction, wherein the Q-switching is one of a plurality of operational modes that are electrically switchable from one to another, and wherein the plurality of operational modes includes both a continuous-wave mode and a Q-switched mode; extracting a first optical signal beam from the Q-switched ring signal laser beam in a free-space portion of the ring optical signal path; separating from the free-space portion of the ring optical signal path at least a portion of any light counter-propagating in the ring optical signal path in a second direction other than the first direction, wherein the separating from the ring optical signal path is spatially separate from the extracting of the first optical signal beam; and forcing a majority of the Q-switched ring signal laser beam to lase in the first direction around the ring optical signal path by reflecting at least a portion of any light separated from the ring optical signal path by the separating to propagate in the ring optical signal path in the first direction.