Bae Systems Information and Electronic Systems Integration Inc.

Peter A Budni

Peter Ketteridge

Daniel J Creeden

Yannick C Morel

Leonard A Pomeranz

Michael J Shaw

Philip R Staver

Scott D Setzler

David Paul Kelly

Joseph M Owen

Michael Lemons

John C Wikman

Evan P Chicklis

Robert C Guyer

Alan R Enman

Chia-Lie Chang

Kevin T Werner

The system and method of using an ultra-short pulse mid and long wave infrared laser. The system is seeded with a 2 &#x3bc;m laser source having a pulse duration in the femtosecond range. The beam is stretched, to increase the pulse duration, and the beam is amplified, to increase an energy level of the laser beam. Both mid wave IR and long wave IR seed beams are first generated, and then amplified via one or more optical parametric chirped-pulse amplification stages. A compressor may be used to compress one or more of the output beams to achieve high peak power and controllable pulse duration in the output beams. The output beams may then be used to create atmospheric or material effects at km range.

Ultra-short pulse mid and long wave infrared laser

The system and method of producing a first path comprising a pulse stretcher for a mid-wave infrared (MWIR) signal, an optical parametric chirped-pulse amplification (OPCPA) amplifier, and a MWIR compressor for producing a first beam in a MWIR portion of the spectrum and a second path comprising a pulse stretcher for a long wave infrared (LWIR) signal, an OPCPA amplifier, and a LWIR compressor for producing a second beam in a LWIR portion of the spectrum. Each beam, on its own, is configured to produce laser-matter interactions at long range (100s of meters), having nonlinear effects and favoring supercontinuum generation spanning multiple octaves, that is temporally and spatially overlapped with the fundamental laser beam.

Optical mixing approach for controlling electro-magnetic attributes of emitted laser pulses

The system and method for enhancing and suppressing radio frequency (RF) emissions in a laser induced plasma system using a second laser. A first igniter laser is used at short pulse widths and a second heater laser is used at longer pulse widths. By varying the energy of the heater laser and/or the timing of the arrival of the heater laser with respect to the igniter laser suppression and/or enhancement of the radio frequency (RF) emission from the induced plasma system is possible.

Enhancement or suppression of electro-magnetic attributes via second laser

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

The system and method for creating plasma flares in air by using an ultra-short pulse laser (USPL) that generates plasma filaments with a short lifetime (in nanoseconds), and by heating these plasma filaments with intense microwave (RF) radiation to induce robust air breakdown, resulting in long lifetime (up to milliseconds) plasma flares in the atmosphere.

Long lifetime plasma flares by laser breakdown of air with intense RF heating

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 combined large mode area, fiber cable amplifier and laser beam transport fiber cable is disclosed that transports laser beams output from a compact, high power, solid state laser to remote locations while improving the beam quality and amplifying the beam to compensate for losses in the fiber cable. The fiber cable is clad and is cladding pumped to compensate for the losses in the fiber cable.

Transport fiber amplifier for beam quality improvement

A system is provided for providing high power, wavelength tunable, laser radiation, the system comprising: a plurality of seeder sources, each the source of the plurality having a different seeder wavelength; a Ytterbium doped amplifier chain, receiving radiation from the plurality of seeder sources and at least one pump source; a second harmonic generator communicating with the Ytterbium doped amplifier chain, the second harmonic generator comprising converting radiation of the seeder wavelength into radiation of a second harmonic wavelength; and wherein the second harmonic generator comprises a crystal having a plurality of grating segments, wherein each grating segment converts radiation of a different wavelength.

Fiber-based wavelength agile visible laser source

An all fiber mid-IR pulse generator is disclosed that may be used to drive an external non-linear converter. The generator comprises fiber laser oscillator and fiber amplifier elements wherein diode lasers are used to cladding pump the different fiber elements depending on different configurations of the pulse generator. Gain switching of the fiber lasers precludes the need for discrete devices such as Q-switches to generate pulses. The fiber laser and fiber amplifier elements are all fused together, along with fiber isolators and reflective gratings, so there is no free space coupling, and there are no optical elements except as may be needed to couple the output of the generator to a non-linear converter. The all fiber implementation has a single transverse mode at the lowest order mode of operation which results in a nearly diffraction limited output which causes non-linear converters to operate more efficiently. To further increase the efficiency of the non-linear converters the fiber laser oscillator has Bragg gratings with a narrow spectral bandwidth of less than 0.5 nanometers.

All fiber pulse generator for pumping a non-linear converter

An integrated broad spectral band waveguide optical parametric oscillator (OPO) is disclosed. In accordance with a preferred embodiment of the present invention, a single pump laser is used to drive multiple oscillator (OPO) channels. The waveguide OPO is preferably made of orientation patterned gallium arsenide. The pump laser can be, for example, a fiber laser, a diode laser or a solid-state laser.

Infrared waveguide optical parametric oscillator

A Ho:YAG crystal laser is disclosed which is doped with less than 2% holmium to reduce the lasing threshold and up-conversion, thereby increasing the operating efficiency of the laser. The laser does not need sensitizer ions so energy mismatches introduced by the sensitizer ions ale eliminated to the thereby increase the efficiency of the laser while minimizing detrimental thermal loading in the laser caused by up-conversion loss processes. The Ho:YAG crystal laser is directly pumped by a Thulium fiber laser at 1.9 &#x3bc;m at the holmiumItoItransition to produce an output at 2.1 &#x3bc;m yielding a very low quantum defect. The laser is embodied as a thulium fiber laser pumped oscillator or an amplifier.

Holmium doped 2.1 micron crystal laser

A directly pumped, un-sensitized, holmium, quasi-two level fiber laser is disclosed that is doped with Holmium active ions between 0.1 and 2.0 percent by atomic weight. This yields greater energy efficiency from the laser because up-conversion losses are minimized, mismatches created by sensitizer ions are eliminated by having no sensitizer ions, and thermal loading of the fiber medium of the laser is thereby reduced. In addition, the pump ratio of the fiber laser is 0.9 which yields a very low quantum defect. The low doping percentage of holmium active ions also eliminates any absorption of its own energy because the power of the diode pumping source is sufficient to cause the laser to reach transparency.

Low quantum defect holmium fiber laser

The present invention is an amplifier for amplifying an optic signal. The amplifier includes a signal source transmitting the signal, which includes a signal portion in the L-band. The signal first passes into a first signal manipulator. The first signal manipulator is one or more collimators and/or concentrators and, in some embodiments, can include dichroics or optical manipulators known to those skilled in the art. An input pump is aligned to overlap the signal with pump light. From the first signal manipulator, the signal and the pump light intersects the erbium doped crystal, wherein the pump light excites the crystal and the signal impinges the crystal, amplifying the signal.

Erbium doped crystal amplifier

Wavelength conversion apparatus is described that utilizes a Kerr cell to modulate the polarization of a pump laser beam having a first wavelength before the beam is input to an optical parametric oscillator/amplifier wavelength converter to generate a laser beam having a second wavelength. By modulating the polarization of the pump laser beam using the Kerr cell, the optical wavelength converter can be controlled to switch on and off or otherwise amplitude modulate the second wavelength laser beam output from the converter, and to correspondingly amplitude modulate the first wavelength and all other laser beams being output from the converter. In addition, with the pump laser beam and the second wavelength laser beam always being output from said wavelength converter there is a substantially constant thermal load on said wavelength converter creating substantially constant thermal lensing in the wavelength converter crystal that may be easily compensated using optical means.

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Nashua, NH, United States of America

Peter A Budni