Abstract: A system for producing laser output from a solid-state laser is described. The laser output comprises two orthogonally polarized axial modes of light at different frequencies having linear polarization. In one embodiment, the two modes are at different frequencies and can be merged together to produce energy waves of variable frequency. This device has applications in microwave generation and velocity measurements.

Abstract: An eye-safe short pulse room-temperature solid state laser emitting at about 2.1 microns is optically pumped by diode lasers emitting at about 1.9 microns Absorption spectra of Ho ions in YAG (Yttrium Aluminum Garnet) and YLF (Yttrium Lithium Fluoride) host crystals are described. Optical pumping is performed by high-power diode lasers emitting at about 1.91 microns consisting of a GaInAsSb/AlGaAsSb quantum-well active region and AlGaAsSb cladding layers grown on GaSb substrates.

Abstract: Apparatus and method for scaling solid-state devices to higher power using multiple sources each of which are separately collimated, followed by focusing of the pump radiation into gain medium colinear to laser mode using a moderated focus. A modularized system is also described.

Abstract: A ytterbium-doped solid state laser including a resonant cavity formed by an input mirror and an output mirror; and a gain medium within the resonant cavity, the gain medium being made of a ytterbium-doped host material having a ytterbium ion doping level and a thickness sufficient to yield single longitudinal mode laser operation when the resonant cavity is pumped by an external light source.

Abstract: Apparatus and method for scaling solid-state devices to higher power using multiple sources each of which are separately collimated, followed by focusing of the pump radiation into gain medium colinear to laser mode using a moderated focus. A modularized system is also described.

Abstract: In a transverse-pumped, solid-state laser, a nonabsorptive cladding surrounds a gain medium. A single transverse mode, namely the TEM.sub.00 mode, is provided. The TEM.sub.00 mode has a cross-sectional diameter greater than a transverse dimension of the gain medium but less than a transverse dimension of the cladding. The required size of the gain medium is minimized while a threshold for laser output is lowered.

Abstract: A source of coherent blue light comprises a diode laser for pumping a Nd.sup.3+ doped member of lasant material disposed within an optical resonator for exciting the .sup.4 F.sub.3/2 -.sup.4 I.sub.9/2 laser transition of a wavelength within the range of 0.870 to 0.960 .mu.m. The laser radiation within the optical resonator is doubled by means of a doubler crystal of a non-linear, electro-optic material to produce blue light which is then extracted from the optical resonator as an output beam. A thermo-electric cooler is coupled in heat-exchanging relation with the Nd.sup.3+ doped laser material to improve the efficiency and the doubler crystal is temperature controlled for phase matching to the laser radiation within the range of 0.870 to 0.960 .mu.m. The diode pump laser is preferably either a GaAlAs or GaAs diode laser producing pumping radiation of a wavelength of approximately 0.810 .mu.m.

Abstract: A semiconductive diode pumped Nd:glass laser is disclosed in which standard low-loss Nd:glass is employed as the gain medium. In some embodiments, miniature optical resonators are employed for resonating the lasant radiation within the gain medium. One or more of the reflectors of the optical resonator are preferably defined by one or more faces of the glass gain medium. Travelling wave, Q-switched, modelocked, second harmonic generating, and slab laser embodiments are disclosed.

Abstract: A monolithic phasematched harmonic generator is obtained by optically pumping an optically nonlinear lasant member having reflective faces defining the monolithic optical resonator. Phasematching is achieved, in one case, by inclining a totally internally reflective face of the resonator at a proper angle relative to other faces of the resonator to angularly separate and resonate lasant waves of the proper polarization. In a second case, a clad fiber resonator of optically nonlinear lasant material has its cladding arranged to guide and thus resonate only lasant waves of the correct polarization. In a third case, the optical nonlinear coefficient of the optically nonlinear lasant material is spatially modulated with a period equal to an odd integer number of coherence lengths, of the harmonic generation process, to obtain quasi-phasematched operation. Phasematched operation improves the efficiency of the harmonic generation process.

Abstract: A miniature solid state near room temperature laser includes a laser crystal doped with a laser ion and an absorber ion. The absorber ion absorbs pumping radiation derived from the output of a laser diode and transfers the absorbed energy to the laser ion for inverting the population of the desired energy transition levels to produce an eyesafe output beam with wavelengths greater than 1.4 microns. In a preferred embodiment, the host crystal is YAG and it is co-doped with Ho as the laser ion and Er as the absorber ion. A small concentration of Tm ion may be doped into the crystal to enhance pumping efficiency. Improved efficiency can be obtained by cooling the laser crystal with a thermoelectric cooler and by tuning the output of the diode laser pump to an absorption peak of the absorbing ion.