Other

Bae Systems Information and Electronic Systems Integration Inc.

Sanders Associates Limited

Lockheed Sanders, Inc.

Thomas M Pollak

Peter G Schunemann

Scott D Setzler

Cathy J Reed

The present invention uses a novel crystal host to minimize parasitic upconversion and lifetime quenching processes by increasing the distance between active dopant ions in the matrix. As a result, erbium that could previously only be useful at low levels may now be incorporated at much higher concentrations without adverse effects. In addition, this host has long excited-state-lifetimes, making it more effective as an energy storage device for pulsed laser applications.

Calcium gallium sulphide (CaGa2S4) as a high gain erbium host

A method for growing solid state laser crystal boules is disclosed that when made into laser rods do not need separate end caps attached to the laser rods. The crystal boule is grown as a single integral unit with three segments. Two segments, the end segments, are un-doped or non-laser active, and they flank a central segment of the boule that is doped with an active laser ion. A first end segment of the crystal boule is first grown from un-doped melt material in a first crucible by slowly withdrawing its growing end from the first melt. The boule is then transferred to a doped melt in a second crucible where its growing end is submersed therein to grow the doped, laser active central segment. The temperature of the melt in the second crucible is initially higher than the growing temperature of the first melt and causes the growing end of the boule to melt. The temperature of the second melt is then lowered and the central segment of the crystal boule is grown onto the first end segment in an integral manner by slowly withdrawing the crystal boule from the melt. After the central segment of the boule has been grown, the boule is removed from the second crucible and is transferred to the un-doped melt in the first crucible where its growing end is submersed therein to grow the doped second end segment. The temperature of the un-doped melt in the first crucible is initially higher than the growing temperature of the second melt and causes the growing end of the crystal boule to melt. The temperature of the un-doped first melt is then lowered and the second end segment of the crystal boule is grown in an integral manner by slowly withdrawing the crystal boule from the un-doped first melt.

Method for growing laser crystals

The present invention provides a method for producing single crystals of a group II-IV-V.sub.2 and group I-III-VI.sub.2 compounds by synthesizing compound material from its constituents and separately melting and refreezing the material in a transparent furnace while observing crystal growth.

Method for growing crystals

A long-life pyrotechnic lamp particularly suited for use in a compact, low-cost laser employing a solid-state laser rod which is pumped by the optical radiation of a pyrotechnic lamp employing the direct combustion of a metal in a flowing oxygen-containing atmosphere. The metal is supported on and heated to ignition by a graphite rod. The metal comprises a cylinder having a centered longitudinal bore adapted to receive the rod therein and has its outer surface serrated or finned to greatly increase the surface area. In one embodiment, the fins are helical about the outer surface. In another embodiment, the outer surface of the metal is longitudinally slit. In both cases, the metal is subsequently sliced into segments.

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Amherst, NH, United States of America

Thomas M Pollak