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AssigneeBAE Systems Information and Electronic Systems Integration Inc.
InventorLeonard A. Pomeranz
Estimating the term…
A Thulium laser (15) is used to directly drive a ZnGeP2 optical parametric oscillator (30) with a nominal 2 μm output to generate the 3-5 micron wavelengths. In one embodiment, the ZGP OPO is configured as a linear resonator and in another embodiment the ZGP OPO is configured as a ring resonator. The ring resonator prevents optical feedback to the Thulium laser (15) and eliminates the need for an optical isolator (24). Moreover, the Thulium laser pump (15) is implemented as a Tm:YAlO3 laser in which YAlO is the host for the Thulium YAlO is particularly beneficial as it is a mechanically hard optical material allowing high thermal loading without fracture as well as natural birefringence that can minimize thermal birefringence losses. A longer wavelength transition at 1.99 microns is selected to minimize nonlinear crystal loss. More particularly, a high power, high efficiency Tm:YAlO3 laser repetitively Q-switched at 10 kHz is used to drive a ZnGeP2 OPO. The system is run with room temperature components and achieves over 3 W at 3-5 microns with an efficiency of 5% starting from the pump diode. A two crystal resonator (40, 42) design allows tuning over multiple spectral peaks or alternately as an ultra broad spectral source.
A method of pumping a wide bandwidth optical parametric oscillator to provide mid-IR radiation output, comprising the step of pumping the optical parametric oscillator with a Thulium laser using a laser wavelength of about 2 microns and operating by itself as a pump source for the optical parametric oscillator, wherein the optical parametric oscillator includes two zinc germanium phosphide non-linear crystals, wherein each of the crystals generates a signal beam and an idler beam that are all part of the output from the optical parametric oscillator, and wherein the signal beams and idler beams generate four distinct wavelengths.
A method of pumping an optical parametric oscillator without utilizing Holmium, comprising the step of pumping the optical parametric oscillator with a Thulium laser using a laser wavelength of about 2 microns output, wherein the optical parametric oscillator includes two zinc germanium phosphide crystals, and wherein each of the crystals generates a signal beam and an idler beam, wherein each of said crystals generates a signal beam and an idler beam that are all part of an output from the optical parametric oscillator, and wherein the signal beams and idler beams generate four distinct wavelengths.
Apparatus for generating infrared radiation, comprising the combination of:
Apparatus for generating infrared radiation, comprising the combination of:
Dependencies are inferred from the claim text.