Butt-coupled single transverse mode diode pumped laser
AssigneeUniversity of South Florida
InventorGeorge J. Dixon
Life of this patent
Estimating the term…
Abstract
A solid state laser is optically pumped by a semiconductive diode. The output facet of the pumping diode is butt-coupled to the input facet of the laser gain medium. The laser gain medium has a short absorption length (<500 um) for the optical pumping radiation such that the pumped mode volume is so small as to support only a single transverse mode of oscillation, i.e., TEM.sub.00 mode operation. In one embodiment a reflector of the laser cavity is formed on the output facet of the pumping diode. In another embodiment the input facet of the laser gain material is bonded to the output facet of the diode pump by means of an index-matching optical cement. The resultant diode pumped laser offers improved frequency stability and reduced size.
Claims23
In a method for obtaining single transverse mode lasing of a diode pumped bulk member of laser gain material, the steps of:
- arranging a member of laser gain material having an absorption length for optical pumping radiation less than 500 micrometers inside an optical resonator having an optical axis passing through the laser gain material;
- butt-coupling the output facet of a semiconductive diode pumping light source to a face of said member of laser gain material and directing a divergent lobe of optical pumping radiation emanating from the diode into the bulk of the laser gain material for optically pumping a sufficiently small volume of laser gain material generally on the optical axis of the resonator so as to excite essentially only a single transverse mode of laser radiation within the laser gain material and optical resonator containing same.
The method of claim 4 wherein the reflective coating deposited on said output facet of said pumping diode is also anti-reflective to the optical pumping radiation passing therethrough.
In a diode pumped solid state laser:
- optical resonator means having a pair of spaced optical reflectors for resonating laser radiation therein and for defining an optical axis of said resonated laser radiation;
- laser means for emitting laser radiation in response to absorption of optical pumping radiation;
- optical pumping means including a semiconductive diode having an output facet for emitting a divergent beam of optical pumping radiation through said output facet;
- said laser gain means including a faceted solid state member of laser gain material having an absorption length for the optical pumping radiation of less than 500 micrometers;
- and
- butt-coupling means for butt-coupling said output facet of said semiconductive diode to an input facet of said faceted solid state member of laser gain material and for directing said divergent beam of optical pumping radiation into said laser gain material generally on said optical axis for optically pumping a sufficiently small volume of said laser gain material so as to excite essentially only a single transverse mode of laser radiation within said laser gain means and optical resonator means.
Dependencies are inferred from the claim text.