Abstract A multistage laser device has in combination a plurality of gas dynamic lasers to obtain a high level of laser power output. A combustor having an exhaust duct with the proper gas constituents is directed into a supersonic nozzle and expanded thereby. During the expansion process a population inversion occurs in the gas constituents which provides a laser action which occurs in a laser region downstream of the expansion nozzle. The gases are then diffused in a variable geometry diffuser and directed into the second supersonic nozzle and re-expanded thereby. A second laser region is formed and the gases are then diffused in a second variable geometry diffuser. This diffuser directs this flow into a third supersonic nozzle and expands it again. A third laser region is formed and the gases are diffused again in a third variable geometry diffuser and directed into the atmosphere or to a turbine for obtaining shaft power necessary for pumps or compressors. The gas dynamic lasers are positioned so that an oscillator can direct a beam into the lasing region of one gas laser through an opening and have it amplified by action therein between two reflecting surfaces and then directed to the exterior of the region through an opening and passed through an interconnecting optical cavity where it is redirected to the lasing region of a second gas laser. The beam is re-amplified by the two reflective surfaces in this region and directed to a second interconnecting optical cavity where the beam is then redirected into the third lasing region of another gas laser. The beam is re-amplified by the reflective surfaces in this third region and directed as a laser output beam through an aerodynamic window. While the gas lasers shown are of the expansion type, it is probably desirable to employ a supersonic-mixing gas dynamic laser configuration for the first unit downstream of the combustor. This is because the supersonic-mixing laser avoids many of the losses associated with rapid kinetic rates at high pressures.
A gas dynamic laser device having in combination a plurality of gas dynamic lasers, each laser having a short supersonic nozzle with an inlet, a lasing region downstream of each nozzle, reflecting walls in each lasing region arranged to form a laser cavity, a diffuser means downstream of each lasing region having an outlet, said lasers being arranged in series with the inlet of the short supersonic nozzle of the first gas laser connected to a device having an exhaust which contains gas constituents which will provide population inversion of excited states by sudden expansion in a supersonic nozzle, the outlet of said diffuser means of the first gas laser being connected to the inlet of the short supersonic nozzle of the second gas laser, optical means for passing a laser beam through the lasing regions in series to provide an output beam.
Claim 2
Dependent Claim
143 words
A gas dynamic laser device having in combination a plurality of gas dynamic lasers, each laser having a short supersonic nozzle with an inlet, a lasing region downstream of each nozzle, reflecting walls in each lasing region arranged to form a laser cavity, a diffuser means downstream of each lasing region having an outlet, said lasers being arranged in series with the inlet of the short supersonic nozzle of the first gas laser connected to a device having an exhaust which contains gas constituents which will provide population inversion of excited states by sudden expansion in a supersonic nozzle, the outlet of said diffuser means of the first gas laser being connected to the inlet of the short supersonic nozzle of the second gas laser, optical means for passing a laser beam through the lasing regions in series to provide an output beam.
Claim 3
Dependent Claim
21 words
A combination as set forth in claim 1 wherein said gas lasers are arranged with the lasing regions adjacent each other.
Claim 4
Dependent Claim
23 words
A combination as set forth in claim 1 wherein said optical means includes an optical cavity between lasing regions of adjacent gas lasers.
Claim 5
Dependent Claim
27 words
A combination as set forth in claim 1 wherein said diffuser means is formed of variable geometry, and means for varying the geometry of said diffuser means.
Claim 6
Dependent Claim
70 words
A combination as set forth in claim 3 wherein said optical means includes an input oscillator for directing a laser beam into the laser cavity of one gas dynamic laser, said laser cavity being capable of amplifying an input beam, said optical means being capable of directing an amplified beam into said optical cavity between lasing regions of adjacent gas lasers for directing the beam into said second gas laser.
Claim 7
Dependent Claim
18 words
A combination as set forth in claim 5 wherein the output beam is passed through an aerodynamic window.