Bae Systems Information and Electronic Systems Integration Inc.

Leonard A Pomeranz

Peter A Budni

Michael J Shaw

Philip R Staver

David Paul Kelly

Joseph M Owen

John C Wikman

Jeffrey L Jew

Scott D Setzler

Hermanus Stephanus Pretorius

Paul R Moffitt

Jojit C Torcedo

A laser system produces pulses having wavelengths between 2000 nm and 2100 nm, peak output powers greater than 1 kW, average powers greater than 10 W, pulse widths variable from 0.5 to 10 nsec, pulse repetition frequencies variable from 0.1 to over 2 MHz, and a pulse extinction of at least 60 dB. Pulses from a diode laser having a wavelength between 1000 nm and 1100 nm are amplified by at least one fiberoptic amplifier and applied as the pump input to an Optical Parametric Amplifier (OPA). A cw laser provides an OPA seed input at a wavelength between 2000 nm and 2200 nm. The idler output of the OPA having difference frequency wavelength between 2000 nm and 2100 nm is further amplified by a crystal amplifier. The fiberoptic amplifier can include Ytterbium-doped fiberoptic. The crystal amplifier can include a Ho:YAG, Ho:YLF, Ho:LuAG, and/or a Ho:Lu2O3 crystal.

High power long wavelength pulsed IR laser system with highly variable pulse width and repetition rate

An active receiver having a digital-pixel focal plane array (DFPA) ranges a target when observing return pulses from a pulsed laser beam synced with the receiver. The DFPA establishes a time when the pulsed laser beam contacts a target and the range can then be established because the speed at which the laser beam travels is known. Various basis functions may be implemented with the DFPA data to establish when the laser beam contacts the target. Some exemplary basis functions are binary basis functions, and other exemplary basis functions are Fourier basis functions.

System and method for ranging a target with a digital-pixel focal plane array

Techniques are provided for a multiwavelength laser source and a method of driving the multiwavelength laser source. The multiwavelength laser source includes: a plurality of seed lasers to generate a corresponding plurality of seed beams having a corresponding plurality of distinct seed wavelengths; a laser combiner to receive and combine the seed beams into a single first beam; an optical amplifier to amplify the first beam; and a single fixed nonlinear converter to convert and output the amplified first beam as a multiwavelength second beam including the seed wavelengths and one or more new wavelengths distinct from and generated from the seed wavelengths. In some embodiments, the nonlinear converter is an optical parametric oscillator (OPO) or an optical parametric generator (OPG). In some other embodiments, the nonlinear converter is a sum frequency generator (SFG), a difference frequency generator (DFG), or an optical parametric amplifier (OPA).

Multiwavelength laser source

Techniques and architecture are disclosed for providing a laser system. In one specific example embodiment, the system includes a thulium-doped fiber laser coupled by silica glass fiber to a remote optical converter (ROC) including a Ho:YAG laser and, optionally, an optical parametric oscillator (OPO) utilizing in germanium phosphide (ZnGeP; ZGP) or orientation-patterned gallium arsenide (OPGaAs). The fiber laser may emit a low-peak-power, continuous wave pump signal that pumps the Ho:YAG laser, which in turn emits a higher-peak-power, pulsed signal. When included, the OPO can be used to convert the resultant, pulsed signal to a longer wavelength (e.g., about 2-5 &#x3bc;m, or greater). In some cases, distributed architecture and reduced weight/bulk may be realized while eliminating the need to actively cool the ROC for operation, for example, over a broad temperature range (e.g., &#x2212;55-125&#xb0; C.). Also, methods of preparing high-peak-power, pulsed signals using such systems are disclosed.

Multi-band laser architecture

Techniques and architecture are disclosed for providing a laser system. In one specific example embodiment, the system includes a thulium-doped fiber laser coupled by silica glass fiber to a remote optical converter (ROC) including a Ho:YAG laser and, optionally, an optical parametric oscillator (OPO) utilizing zinc germanium phosphide (ZnGeP; ZGP) or orientation-patterned gallium arsenide (OPGaAs). The fiber laser may emit a low-peak-power, continuous wave pump signal that pumps the Ho:YAG laser, which in turn emits a higher-peak-power, pulsed signal. When included, the OPO can be used to convert the resultant, pulsed signal to a longer wavelength (e.g., about 2-5 &#x3bc;m, or greater). In some cases, distributed architecture and reduced weight/bulk may be realized while eliminating the need to actively cool the ROC for operation, for example, over a broad temperature range (e.g., &#x2212;55-125&#xb0; C.). Also, methods of preparing high-peak-power, pulsed signals using such systems are disclosed.

A Thulium laser () is used to directly drive a ZnGePoptical parametric oscillator () with a nominal 2 &#x3bc;m 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 () and eliminates the need for an optical isolator (). Moreover, the Thulium laser pump () is implemented as a Tm:YAlOlaser 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:YAlOlaser repetitively Q-switched at 10 kHz is used to drive a ZnGePOPO. 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 () design allows tuning over multiple spectral peaks or alternately as an ultra broad spectral source.

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Hollis, NH, United States of America

Leonard A Pomeranz