Active Mirror Laser Amplifier Pumped by New Solid State Light Source Using Selective Thermal Emission

A new light source using dielectric solids has been under development since the 1980s for thermophotovoltaic (TPV) generation of electricity. The light source is a dielectric refractory solid emitter heated to relatively high temperatures (~1 500_C) by combustion, nuclear or other heat sources. This new light technology has now reached the maturity to be applied to the optical pumping of high power solid-state lasers. For the new light source, a dielectric solid, either crystal or ceramic, is chosen to have selective thermal emission ("superemissive") with nearly narrowband emission (~100 nrn) peaked in the visible-infrared spectrum. For TPV, Quantum Group Inc. has demonstrated a high-power superemissive unit (patent pending) called Advanced Emissive Matrix (AEM) having more than 5X power density than any commercial combustor. Using AEM to pump a large-aperture ('4 cm) Active Mirror laser amplifier can achieve high beam-quality (one to two times diffraction limit), high efficiency, high repetition rate lasers. The large round clear aperture of the Active Mirror reduces the diffraction problems encountered in laser slab and rod amplifiers. Because of its solid-state basis, superernitters are scalable to high powers (>1000 Watts) and long life (>10,000 hours). Superemitters can be a self-powered, self-contained, efficient (40%) light source, offering a replacement for expensive laser diodes and inefflcient flashlarnps in laser pumping. Self-powered lasers pumped bv AEM (Jive self-contained mobile svstems needed for applications in isolated environrnents as satellites, submarines, battlefields and third-world countries, where traditional electrical power is restricted or intermittent. AEM-pumped high power lasers will be very useful in commercial factories for material processing.