US Government As Represented by the Secretary of the Army

The United States of America As Represented by the Department of Health

Other

John E Nettleton

Dallas N Barr

Brian C Redman

Bradley W Schilling

Clifton S Fox

Jonathan S Lei

Lew Goldberg

Michael M Quarles

James D Habersat

Charlie W Trussell

Brian J Cole

Nathaniel L Hough

Elmer C Sluss

The compact, laser cavity with a single-axis scanning element as the optical Q-switch incorporates all optical components required for a short-pulse laser. These optical components are 'locked' into alignment forming an optical laser cavity for diode laser or flash lamp pumping. The optical laser cavity does not need optical alignment after it is fabricated. Unfortunately, during the alignment process of the optical laser cavity there are small shifts due to the bonding process of the optical elements. These small shifts introduce alignment errors which results in a decrease in output energy and beam quality. The improvement presented adds a single circular wedge prism that corrects these alignment errors returning the output back to its optimum energy output and beam quality.

Process using a single circular wedge prism for fine alignment of a laser cavity with a single-axis scanning element as the optical Q-switch

A monoblock laser cavity incorporates optical components for a short-pulse laser. These optical components are 'locked' into alignment forming an optical laser cavity for flash lamp or diode laser pumping. The optical laser cavity does not need optical alignment after it is fabricated, increasing the brightness of the monoblock laser.

Beam quality of the monoblock laser through use of a 1.5 micron external cavity partial reflector

A method and device for reducing the timing jitter in a passive Q-switched Nd:YAG solid state laser by spatially selective bleaching a thin sheet of a saturable absorber of Cr:YAG from a direction orthogonal to the direction of laser emission where the Cr:YAG transmission increases 18% when the bleaching probe beam is a single laser diode bar. For steady state operation of a passive Q-switched laser, the pulse-to-pulse timing jitter showed a &#x2212;12&#xd7; reduction in standard deviation from 241 nsec for free running operation to 20 nsec with optical triggering.

Reduction of timing jitter in a passive Q-switched solid state laser

A laser gain medium crystal comprising a square rod of laser gain medium material having top and bottom surfaces that are finely ground to introduce scattering surfaces to cancel parasitic lasing. The square rod of laser gain material has input and output faces and side surfaces, and portions of the side surfaces near the output face of the square rod are finely ground to introduce scattering surfaces to cancel parasitic lasing. The rest of the side surfaces of the square rod are polished.

Suppression of parasitic lasing

A process for optically aligning a laser rangefinder that includes the steps of providing a laser rangefinder having a laser source, a photodetector lens and a photodetector, providing a fiber optic travel path, aligning the laser source to the fiber optic travel path, illuminating the photodetector with a light source, focusing the photodetector lens, coupling the fiber optic travel path to an optical light source, and aligning the fiber optic light relative to the photodetector.

Process to optically align a photoreceiver with a laser transmitter source in a laser rangefinder system

A YAG/Nd:YAG block where an Nd:YAG block ends in a peak integrated inside a YAG block. The YAG block has reflective surfaces positioned at 45&#xb0; to one another. The angled reflective surfaces serve as a 'mirror' within the laser cavity to effectively increase the length of the cavity by a factor greater than 2. Fused to the output end of the laser cavity are a polarizer, an active/passive Q-switch, a one quarter waveplate and an output coupler. In operation, the laser cavity is pumped either from the side or the end of the cavity. The optical components of the present invention are bonded to form one optical 'block'. All the components are prealigned during the crystal manufacturing process to form the optical laser cavity. The width of the cavity should be selected such that nearly all of the laser diode pump output is absorbed by the cavity.

Mono-slab laser cavity

A monoblock laser cavity includes a plurality of discrete optical components disposed serially on a substrate and sharing a common optical axis. The optical components include a laser rod of gain material, a Q-switch, an OPO crystal, and an output coupler. The output coupler has at least one convex end face to improve the beam quality.

Unstable monoblock laser cavity

A monoblock laser cavity includes a plurality of discrete optical components disposed serially on a substrate and sharing a common optical axis. The optical components include a laser rod of gain material, a Q-switch, an OPO crystal, an output coupler, and a positive lens. The output coupler has a convex input end face and a concave output end face, and acts as the expanding lens element of a beam expander, and the positive lens completes the beam expander to improve the beam quality.

Unstable monoblock laser cavity with integrated beam expander

An improved monoblock laser cavity is made by elongating the Optical parametric oscillation (OPO) cavity. This can be accomplished by changing the coatings on the OPO material and Q-switch and by elongating the OPO cavity to approximately 2 to 3 times the OPO crystal length. The increase in the length of the OPO cavity will improve the beam divergence of the laser.

Monoblock laser

A system, called the Laser Aim Scoring System, and method for automatically scoring gunner training sessions for simulated laser-guided missile, target engagements using the laser designator without the need for training or tactical rounds are disclosed. In the disclosed invention, a pop-up target and its surrounds are separately monitored for radiations at the laser designator frequency. 'Hit' or 'Miss' scoring is based on detection of the laser radiation at the laser designator frequency illuminating the appropriate region around or on the target at the appropriate time with respect to a simulated missile launch signal at the start of the training engagement, in accordance with the engagement profile programmed into the scoring computer prior to the start of training. The laser aim scoring system send a signal to lower the pop-up target in response to a &#x201c;Hit&#x201d; score, and if desired by the user, also sends a signal to initiate smoke and flash signals from a Hoffman Kill Simulator interfaced with the system. The disclosed invention also sends the appropriate signals at the end of the engagement to reset the target in the upright position so that it is ready for the next engagement. The disclosed invention includes subsystems for transmitting data, video imagery, and control signals between the portion of the system at the target location and the portion of the system at the control tower.

Laser aim scoring system

The laser obstacle avoidance device of the present invention includes an optical head which includes a laser source which produces a laser signal, crossed cylindrical lenses and through which the laser signal is transmitted, a transceiver including a receiving lens through which a reflected laser signal is received by the transceiver, a receiver and a line filter through which the reflected laser signal is filtered, and scanners which receive the reflected laser signal; and control electronics optically connected to the optical head, wherein the control electronics comprise scanner driver electronics, range processor electronics, power converters, and a display all which produce an x-y display of the terrain scanned by the laser signal wherein the X-axis is driven by a scanner position output and the Y-axis by range data. The system was designed to avoid hazards with emphasis simplicity and low cost. The device has been employed in the field to collect data from natural and man-made objects. A simple, single scan line, range discontinuity detection program has been written and tested. The next step in the process is to interface the output of the processor with driver's display indicating the location of the potential hazard for the operator's closer scrutiny.

Laser obstacle avoidance apparartus

A multi-function combat laser is described that uses single or multiple laser sources (laser diodes) in a configuration such that when it is coupled with a dichroic substrate the laser sources outputs are coupled to produce a single desired output. The multi-function combat laser consolidates multiple laser functions for the dismounted soldier into a single package with shared power supplies, optics and laser sources.

Multi-function combat laser for the dismounted soldier

The End Pumped Slab Laser Cavity incorporates all optical components required for a short-pulse laser. These optical components are 'locked' into alignment forming an optical laser cavity for diode laser or flash lamp pumping. The optical laser cavity never needs optical alignment after it is fabricated. The cavity is configured for optimal absorbtion for diode laser end-pumping over broad temperature ranges.

End pumped slab laser cavity

A one piece laser assembly including a rod of gain medium with one end-face bonded to a broad end-face on a stack of optical wafers that process light differently and mirrors plated on the remaining exposed end-faces of the rod and the stack of wafers.

Growing community of inventors

Fairfax Station, VA, United States of America

John E Nettleton