Laser diode side pumping of an elongated solid-state laser without focusing|optics

摘要

A side pumped laser comprises an elongated gain medium (10) provided between an output coupler (20) and a counter reflector(15) and a pump source(65) configured to provide radiation to the gain medium (10) along a side axis of the gain medium, wherein the laser is configured such that radiation from the pump source is directly incident on the gain medium; and the pump source is provided proximate, adjacent or in contact with the gain medium. The laser material and compositions, geometries and dimensions are designed to both maximise laser performance and to permit the use of construction techniques commonplace in the production of equipment designed for optical telecoms systems to facilitate low cost high volume and miniaturisation. The elongated gain medium (10) may have a polygonal cross-section with a non-coated side surface (55) receiving pump light emitted by a laser diode bar (65) while the other, non-emitting surfaces are coated with for example a gold coating (60) for pump light recycling and cooling of the gain medium by heat conduction. The counter reflector (15) may be provided on one facet of a passive Q-switch (30) and the output coupler (20) on a facet (50b) of the gain medium (10).