Litton Systems, Inc.

Northrop Grumman Systems Corporation

Steve Guch, Jr

Ronald R Selleck

Floyd E Hovis

Charles L Stonecypher

Anna Tabirian

Douglas P Stanley

Bart A Shepherd

Chris Radcliffe

William M Roberts

Lloyd H Morton

A lasing apparatus includes a laser medium and a pump source. The laser medium includes one of a Holmium-doped fluoride crystal or a Holmium-doped fluorozirconate ZBLAN glass fiber. The pump source generates pulses that resonantly pump the laser medium such that the laser medium produces an output from theIlevel to theIlevel of Holmium. The pump source produces pulses having a duration that is at least as long as a storage time of theIlevel of the laser medium. The pump source pumps the laser medium with signals having a wavelength shorter than 1.67 &#x3bc;m, with the laser medium producing an output having a wavelength of about 1.67 &#x3bc;m.

Method and apparatus for producing an eye-safe laser

A laser apparatus is described having multiple modes of operation using intracavity optical switching within a laser resonator. The laser resonator has a solid state gain medium and one or more optical switches located between a pair of end reflectors. The pump for the gain medium has controlled duration to allow varying the pumping energy and pulse repetition rate. The laser has a Q-switched mode for generating energy from the laser resonator at a fixed level of outcoupling when the laser pump is operated to produce a range of predetermined pulse, rates and durations. The laser also has a cavity dumped mode of operation in which the laser pump is operated to produce a second range of predetermined higher pulse repetition rates and shorter pulse durations so that the pulse energy, rate and duration are selected by first Q-switching with essentially no outcoupling and then rapidly cavity dumping all the optical energy in the resonator. Intracavity optical switching of the laser resonator is used to achieve the two distinct modes of operation, the first being conventional Q-switched operation with pulse width equivalent to several cavity round trip times and the second being Q-switched cavity, dumped operation with pulse width equivalent to about one cavity round trip time. Use of this apparatus with external frequency shifting optics is also described.

Multiple mode laser

A microlaser is provided that has a microresonator and a pump source for side pumping the microresonator. The microresonator includes an active gain medium and a Q-switch that extend lengthwise between the opposed end faces of the microresonator. The pump source is therefore positioned so as to introduce pump signals into the microresonator via the side surface that is adjacent to and defined by the active gain medium. By side pumping the microresonator, the microlaser can generate a series of pulses having greater pulse energies and greater average power levels than the pulses provided by conventional microlasers. In addition, the side pumped microlaser can also generate pulses having greater pulse widths than the pulses provided by conventional microlasers of a similar size. As such, the side pumped microlaser can be employed in more demanding applications that require pulses having greater pulse widths as well as pulses that have greater pulse energy and greater average power than are typically provided by conventional end pumped microlasers.

Side pumped, Q-switched microlaser

A boresight alignment method is used for aligning a laser with an optical sighting system in a laser designator or the like. The method includes selecting a target formed of a flat sheet of material, such as a metal foil, supporting the selected target at the focus of a collimating telescope in the path of a laser beam of a laser and optical sighting system combination, such as in a laser designator, focusing the laser beam onto the one side of the target, and burning an aperture in the target with the laser beam. The method includes illuminating the target burned aperture from the rear thereof with a visible light or with an infrared source and then aligning the optical sighting system with the illuminated target aperture. Both the day and night viewing optics can be aligned by providing pinhole illumination with multi-spectral target pinhole illumination. The target may be mounted so that it can be rotated to provide successive alignments of the same or different laser optical sighting systems. The target can be an aluminum foil supported on a metal frame or with a paper or polymer backing. An optical sighting system can be aligned to a laser with high accuracy under rugged military and industrial field operating conditions.

Boresight alignment method

A laser diode pumped laser has a laser diode wavelength sensing and control apparatus. A laser medium is mounted in a laser cavity and has a laser diode pump having a laser diode or laser diode array having an output of a predetermined wavelength for exciting the laser medium. An optical radiation detector is coupled to the output of the laser medium to receive and measure the radiation from the laser diode transmitted through the laser medium and a detector bias and signal measurement circuit is coupled to the optical radiation detector to receive signals therefrom and generate an output signal responsive to the optical radiation detector signals and to apply the generated signals to the laser diode power supply (or to diode heaters) to vary the power supply output to vary the laser diode wavelength to maintain the laser diode wavelength at the absorption peak of the laser medium. A method of sensing and controlling the laser diode pump wavelength for a laser includes selecting a laser in accordance with the apparatus and coupling the selected detector bias and signal measurement circuit to the optical radiation detector to receive signals therefrom and generate output signals responsive to the optical radiation detector signals and coupling the radiation bias in the signalling measuring circuit to the laser diode power supply to vary the diode power supply output to vary the laser diode wavelength to maintain the output near the absorption peak of the laser medium.

Laser diode pump wavelength sensing and control apparatus and method

A method and apparatus for testing materials for use in a laser resonator includes selecting a test fixture apparatus having a housing with an internal chamber volume selected to approximate the internal volume of a predetermined laser resonator and having a pair of sealed windows therein which are removably attached to the housing and having optical coatings selected to match the coating on the optics of a laser. The housing has a removable cover and a gas purging opening. A laser of a predetermined wavelength and power is mounted adjacent the test fixture and is aligned for directing the laser beam through both of the windows of the test fixture. A material is placed in the test fixture and a laser beam directed through the coated windows for a predetermined period of time and thereafter the coated windows are examined for damage or contamination. The test fixtures are also cleaned and certified prior to testing so that a preselected test fixture can determine damage for selective materials used therein.

Method and apparatus for testing materials for use in a laser resonator

A decontaminate apparatus for a laser system includes a laser having a compartment housing having a base and walls formed into a cavity and having a compartment cover having at least a portion thereof porous to predetermined gases used in laser system optical cavities. The compartment housing cavity is filled with a selected decontaminating material held therein by the porous cover and is attached in the laser system housing so that selected contamination in the laser system optical compartment gas is absorbed by the selected material in the compartment. The compartment cover can be made of a porous silica. A method of cleaning a laser optical cavity includes forming the housing having the cavity therein, selecting a decontaminate material, placing the selected decontaminate material into the housing, and forming and attaching a cover, at least a portion of which is porous to predetermined gases used in laser optical cavities, and attaching the housing with the selected material in the laser cavity so that selected contamination in the laser system optical cavity gas is absorbed by the selected material.

Growing community of inventors

Mount Dora, FL, United States of America

Steve Guch, Jr