Method and apparatus for compensating thermal lensing effects in a laser cavity

摘要

In a laser cavity having an optical axis, a laser medium for forming a laser beam, the laser medium having a central axis off-set from the optical axis, the laser medium exhibiting focusing characteristics that vary with changes in optical power pumped into the laser medium, at least one pair of mirrors oppositely positioned for reflecting at least a portion of the laser beam, one of the mirrors being an output coupler, the laser cavity further comprising at least one focusing element having a central axis positioned between one of the mirrors and the laser medium such that the central axis of the focusing element is displaced from the optical axis a distance that is a function of the displacement of the laser medium central axis from the optical axis and the optical axis passes through the focusing element to substantially eliminate lensing effects produced by the laser medium.