Fibre laser

摘要

A fiber laser having an optical cavity that has an optical fiber and a curved mirror for imaging light leaving the fiber back into the fiber. The optical fiber has a round trip dispersion loss of less than 200000 fs2. The round trip length of the optical fiber is less than 2.3 m.

主权项

1. A mode locked fibre laser comprising an optical cavity, wherein the optical cavity comprises:
an optical fibre comprising a gain medium, a first optical fibre end, a second optical fibre end, and an optical fibre length; a first collimator, wherein the first collimator is configured to collimate light from the first optical fibre end; a second collimator, wherein the second collimator is configured to image light into the second optical fibre end; a free space optical path between the first collimator and the second collimator comprising a free space optical path length, wherein the free space optical path length is greater than the optical fibre length; a curved mirror within the free space optical path, wherein,
the curved mirror is located at a first distance from the first collimator and at a second distance from the second collimator;the curved mirror is characterized by a radius of curvature characterized by a focal length wherein the focal length is less than the second distance; andthe radius of curvature and the location of the curved mirror within the free space optical path is configured to image light from the first collimator into the second collimator and thereby increase optical-to-optical coupling efficiency and reduce diffraction loss; and at least one mode locking element optically coupled to the free space optical path.