Abstract: Frequency conversion methods are taught wherein non-collinear phase matching configurations may be implemented in non-linear crystals used in three wave mixing processes such that the frequency conversion efficiency is enhanced through walk-off compensation while also maximizing conversion efficiency. The harmonic conversion techniques are especially applicable to sum frequency process, and in particular to third harmonic generation.

Abstract: An assembly for providing a concentrated, vertically stacked array of laser beams from a horizontally offset array of electrically serially-connected metallic microchannel heat sinks each bearing a laser diode bar. The heat sinks are mounted on horizontally offset planes of the manifold which has coolant channels serving adjacent heat sinks that are separated from each to increase the electrical resistance of the fluid path between adjacent ones of said heat sinks. Stepped optical deflectors re-arrange the horizontally emitted laser beams into vertical stack.

Abstract: An optical system includes a diode pump source and a thin disk gain media. The thin disk gain media has first and second surfaces and is made of a material with an anisotropic thermal expansion. At least one of the first and second surfaces is a cooling surface. The thin disk gain media is cut at an angle to provide substantially the same thermal expansion coefficient in all directions lying in a plane that is parallel to the cooling surface. An optical coupler is positioned between the diode pump source and the thin disk gain media to direct an output from the diode pump source to the thin disk gain media.

Abstract: A diode end-pumped solid state laser is provided which produces improved power output, long term stability and improved conversion efficiency from the pumping power, high as well as low power operation while maintaining certain desirable common characteristics such as TEM00 operation, circular outputs, readily aligned systems and compatibility with long lifetime for all components. The invention intracavity conversion to second, third and higher harmonics in several different spectral regimes. The invention also addresses the aspects of design flexibility, seeking in certain embodiments to provide a single platform for providing several harmonic beams.

Abstract: A regenerative amplifier system that is optimized for low-gain gain media is provided. The system is configured to include a minimum number of intra-cavity elements while still eliminating the leakage of the seed pulses from the output beam. In addition, the contrast ratio of the amplified pulses is increased even considering the long build-up time that is required in low-gain regenerative amplifiers. This is accomplished using a single Pockels cell between the oscillator and amplifier to select a single seed pulse for the cavity, instead of using a Faraday isolator. This directs the unwanted seed pulses in a separate direction from the output pulse. When the amplified pulse exits the cavity, it is directed in a direction away from the oscillator by the same Pockels cell. Only one additional Pockels cell and one polarizer are required inside the regenerative amplifier cavity.

Abstract: An optical system has a high power diode pump source and a thin disk gain media. An optical coupler is positioned between the diode pump source and the thin disk gain media. The optical coupler produces a beam with a large numerical aperture incident on the thin disk gain media.

Abstract: An optically pumped laser has a gain medium positioned inside of an optical resonator cavity and disposed about a resonator optical axis. An optical pumping source is positioned outside of the optical resonator cavity. A reflective coupler with a coupler body, and an interior volume passing therethrough is positioned proximal to the optical pumping source. Light from the pumping source passes into an entrance aperture of the reflective coupler to an exit aperture of the reflective coupler positioned distal to the optical pumping source. The interior volume of the reflective coupler is bounded by a reflective surface, an entrance aperture and the exit aperture, and is substantially transparent to radiation from the optical pumping source. The reflective surface has a high reflectivity matched to radiation from the optical pumping source.

Abstract: A laser device is provided for generating an ultraviolet output. The device comprises a laser having at least one diode-pumped alkali metal vapor gain cell for generating a near infrared laser output, and at least two optically-nonlinear crystals. In one particular embodiment, the laser uses a Rb gas cell and generates radiation at a wavelength of about 199 nm and at least 200 mW of power with a linewidth of less than 10 GHz. In another embodiment, narrow linewidth UV light is generated at 265 nm.

Abstract: A method of suppression of Indium carry-over in the MOCVD growth of thin InGaAsP quantum wells, with low Indium content, on top of thick GaInAsP, with high Indium content. These quantum wells are essential in the stimulated emission of 808 to 880 nm phosphorous-based laser structures. The Indium carryover effect is larger in large multi wafer reactors and therefore is this invention focused on large multiwafer MOCVD reactors. This invention improves the quality of the quantum well, as measured by photo-luminescence spectra and uniformity of wavelength radiation.

Abstract: Wavelength stability of an optical oscillator has been enhanced by feedback from an external position-sensing detector to control the position or tilt of an intracavity optical element, such as a mirror. The wavelength stability results from stabilization of the intracavity beam position relative to an aperture in the oscillator. The wavelength selectivity of the aperture results from incorporation of a dispersive element in the oscillator cavity that produces a mapping of wavelength to beam position at the aperture.

Abstract: An optical system has a diode pump source, and a gain media made of a material with an anisotropic absorption. The gain media is cut at an angle to produce substantially polarization-independent absorption of a pump beam. An optical coupler is positioned between the diode pump source and the gain media. The optical coupler produces a pump beam that has substantially equal amounts of pump power along any two orthogonal axis that are orthogonal to the pump beam in the gain medium. The wavelength range allowed for the pump source is extended.

Abstract: A method and system are described aimed at substantially increasing the lifetime of sensitive optical elements subjected to high power laser radiation. The lifetime enhancement is accomplished by spatially distributing the laser beam spots both globally and locally according to algorithms that are custom tailored to the subject element as well as the system and application needs. The methods of the invention are particularly well-suited to non-linear crystals used to convert radiation from high repetition rate, diode-pumped laser systems into the UV spectral range, where lifetime requirements are particularly challenging. The methods of the invention further enable effective utilization of available experimental data characterizing the element's performance in combination with a stored library of preferred spot scanning patterns that may be executed on the surface of the element according to the selected algorithm.

Abstract: A wafer that is cleaved to provide a facet for a Fabry-Perot cavity is provided with Bragg gratings whose axes are offset by a small angle from the axis of the Fabry Perot cavity to offset the effect of the randomly uncontrollable location of the cleaved facet on the optical phase of the grating feedback.

Abstract: A laser system includes a pump source that produces a first output. The pump source has a feedback loop with a first summing junction and a first command that has step quantization or digitized set point. An output device is coupled to the pump source to receive the first output and produce a second output. A feedback loop is coupled to the first summing junction. The feedback loop includes a second summing junction coupled to at least a portion of the second output. The second summing junction receives a second command and provides an input to the first summing junction. The feedback loop reduces the step quantization from the first output to provide finer control step of a property of the second output.

Abstract: A laser apparatus includes a modelocked laser system with a high reflector and an output coupler that define an oscillator cavity. An output beam is produced from the oscillator cavity. A gain medium and a modelocking device are positioned in the oscillator cavity. A diode pump source produces a pump beam that is incident on the gain medium. A second harmonic generator is coupled to the oscillator cavity. A third harmonic generator that produces a UV output beam, is coupled to the second harmonic generator. A photonic crystal fiber is provided with a proximal end coupled to the laser system. A delivery device is coupled to a distal portion of the photonic crystal fiber.

Abstract: A method and apparatus are provided for in situ protection of sensitive optical materials from alternation or damage due to exposure to trace atmospheric components, during shipping, storage or operation. The sensitive optical material is disposed within an enclosure adaptable to be substantially sealed against the external atmosphere. A container, enclosing a sink material absorbing trace atmospheric components, is coupled to the enclosure by a gas permeable surface, which allows fast diffusion of the trace atmospheric component inside the enclosure to the sink material.

Abstract: An optically pumped laser has a gain medium positioned inside of an optical resonator cavity and disposed about a resonator optical axis. An optical pumping source is positioned outside of the optical resonator cavity. A reflective coupler with a coupler body, and an interior volume passing therethrough is positioned proximal to the optical pumping source. Light from the pumping source passes into an entrance aperture of the reflective coupler to an exit aperture of the reflective coupler positioned distal to the optical pumping source. The interior volume of the reflective coupler is bounded by a reflective surface, an entrance aperture and the exit aperture, and is substantially transparent to radiation from the optical pumping source. The reflective surface has a high reflectivity matched to radiation from the optical pumping source.

Abstract: A diode pumped, multi axial mode, intracavity doubled, intracavity tripled laser, includes at least two resonator mirrors defining a resonator cavity. A laser crystal and a doubling crystal are positioned in the resonator cavity. A tripling crystal is also positioned in the resonator cavity. A diode pump source supplies a pump beam to the laser crystal and produces a laser crystal beam with a plurality of axial modes that are incident on the doubling crystal. This produces a frequency doubled output beam. Further, a diode pumped, multi axial mode, intracavity nonlinearly-converted laser is provided and includes at least two resonator mirrors defining a resonator cavity, a laser crystal and a nonlinear conversion apparatus positioned in the resonator cavity. A nonlinear conversion apparatus is also positioned in the resonator cavity.

Abstract: A diode pumped laser includes a resonator mirror and an output coupler, defining a laser resonator with a resonator optical axis. A strong thermal lens gain medium with a TEM.sub.00 mode diameter is mounted in the resonator along the resonator optical axis. The dopant level of the gain medium is in the range of 0.01 to less than 0.5 percent. A diode pump source supplies a pump beam to the gain medium in the laser resonator, and produces an output beam with a diameter larger than the TEM.sub.00 mode diameter to reduce thermal birefringence. A power source supplies power to the diode pump source. A polarizing element can be positioned in the resonator, along with a aperture stop The laser operates well over a large range of pump powers. Its slope efficiency in the TEM.sub.00 mode is greater than 40%, with an overall efficiency greater than 25%. One of the gain mediums used is Nd:YVO.sub.4. This material exhibits high gain and a short upper state lifetime.