Abstract: A slab waveguide pumped channel waveguide laser includes a slab waveguide having a primary pump guiding layer with a first index of refraction and having first and second opposing faces and a peripheral edge including a mirrored surface, and cladding means having a second index of refraction lower than the first index of refraction, proximate the first and second opposing faces; at least one rare earth doped channel waveguide laser having a third index of refraction higher than the first index of refraction disposed in the primary guiding layer; and means for introducing pumping energy into the guiding layer to reflect between the mirror surfaces and energize the laser.

Abstract: An edge emitting laser combines many of the desirable attributes of the common forms of surface-emitting and edge-emitting laser structures together with elimination of their drawbacks. The laser cavity of a device according to the present invention is short (on the order of the wavelength of light in the cavity medium) and current is injected into the optical cavity substantially perpendicular to the plane of emitted light and parallel to the plane of reflective mirrors. The use of a short optical cavity permits single mode laser operation because of broad mode to mode spacing and large changes in reflectivity between wavelengths. Injecting current into the cavity perpendicular to the direction of light emission provides low power operation because the resistance associated with the injected current is low. The resistance is low because current does not cross boundaries between the different material layers forming the reflective mirrors and the optical cavity.

Abstract: The effects of polarization dependent hole burning and/or polarization dependent loss are reduced by modulating the state of polarization (SOP) of an arbitrarily polarized optical signal being launched into the transmission path periodically through a predetermined sequence of polarization states. The sequence of polarization states is selected such that on average the launched modulated signal excites substantially all possible polarization states with substantially equal probability, independent of the input SOP to the polarization modulator. In one exemplary embodiment, the SOP is modulated by a combination cascade of a rotating half-wave plate followed by a quarter-wave plate, which rotates at a different angular speed. In another exemplary embodiment, the SOP is modulated by a combination cascade of two variable phase retarders oriented at fixed angles of 0.degree. and 45.degree., where the modulation frequencies of the two retarders are substantially different from each other.

Abstract: A laser system and power control have a polarization state changer that produces in response to an incident beam with selected polarization state at a first wavelength .lambda..sub.1 a beam at .lambda..sub.1 with a desired polarization state. A frequency converter responds to the beam at .lambda..sub.1 with the desired polarization state to produce a frequency converted beam at a second, different wavelength .lambda..sub.2. When the polarization state changer and the frequency converter are located within a laser cavity, the laser system is operable in three different states and produces an output beam at .lambda..sub.1 or .lambda..sub.2, or no output beam, depending on the polarization state changer. In this intracavity configuration the polarization state changer is also operable as a Q-switch.

Abstract: Apparatus and method of non-mechanical scanning a laser diode light beam by altering the wavelength of the beam through changes in current applied to the diode and applying the beam to a diffraction grating to change the position of the beam as it emerges from the grating. A second dimension is scanned by the employment of an acousto-optic deflector and electronic driving and control means to change the position of the beam as it emerges from the deflector.

Abstract: A gas discharge laser includes a cylindrical symmetric discharge tube, having a prescribed gas therein at a low pressure, centered within a microwave-resonant cavity immersed in an axial magnetic field. Appropriate mirrors, optically aligned with a longitudinal axis of the discharge tube, are positioned at each end of the plasma column, one of which is partially transmissive. A pair of Brewster windows, or a pair of flat windows with antireflective coatings, one at each end of the discharge tube, are interposed between the mirror and discharge tube. Electromagnetic energy in the microwave range, e.g., greater than 1 GHz, is injected into the cavity and made to resonate in an appropriate mode. A large portion of the resonating energy is coupled into the discharge tube, causing a plasma to be created and maintained. The axial magnetic field confines the plasma to the center regions of the discharge tube, away from the walls, so as to form a plasma column.

Abstract: A laser oscillator comprising a laser resonator having a plurality of mirrors for directing the laser energy from source to exit apertures, the mirrors being constructed and mounted adjustably for reducing parasitic oscillations. The mirrors are mounted in adjusting members that have channels therein for coolant and are provided with heat insulating members that minimize heat gradients and unwanted heat transfers that may result in the distortion of the reflecting surfaces. In addition, the mirrors are angled so that light paths are defined that present a Z-shaped turning pattern. Apertures proximate to the mirrors through which the light beams are directed are offset from a common plane so that a reflective surface is not within the aperture of the opposing reflective surface. One or more of the apertures can be so offset to reduce the possibility of parasitic oscillations. Further, the reflectors can be angled and the apertures sized so as to eliminate parasitic oscillations.

Abstract: A semiconductor-laser-pumped solid-state laser apparatus having a semiconductor laser device, a solid state laser medium, and laser resonators. The semiconductor laser device has a plurality of emission points which are arranged on a straight line and from which pump light is generated. The laser resonators are disposed in correspondence with the emission points. A plurality of solid state laser beams can be generated by using one solid state laser medium.

Abstract: A VCSEL including a first mirror stack, an active region and a second mirror stack positioned on a substrate with portions of the active region and the first and second mirror stacks being offset from surrounding portions by an offset area in the surface of the substrate so as to define a lateral waveguide which confines the operating region of the VCSEL. The surrounding portions of the second mirror stack are removed to provide current control and refractory metal contacts are formed on the upper and lower surfaces. Methods of fabricating the offset as a depression or a mesa in the surface of the substrate and the resulting VCSEL are disclosed.

Abstract: Visible laser light output from an electrically injected vertical cavity surface emitting laser (VSCEL) diode is enabled by the addition of phase-matching spacer layers on either side of the active region to form the optical cavity. The spacer layers comprise InAlP which act as charge carrier confinement means. Distributed Bragg reflector layers are formed on either side of the optical cavity to act as mirrors.

Abstract: Disclosed herein is an all-optical regenerator which is controlled by an external input optical signal for the generation of an output optical signal satisfying certain preset parameters defining the shape and the amplitude of the output optical signal. The optical device comprises a rectangular phase modulator optically coupled between two resonators so that the inlet mirrors of the resonators and the phase modulator form a nonlinear Fabry-Perot interferometer. The phase modulator serves to generate an output signal of a predetermined or desired pulse width and amplitude. The present optical device also includes a multielectrode injection laser which is optically coupled to the phase modulator. The multielectrode injection laser selects the clock frequency and locks output pulses in conformity with the period of the clock frequency.

Abstract: A solid-state laser resonator includes a pair of reflectors 4, 5, a bar-like laser medium 6, a plurality of point laser sources 1, 2 and resonator including a plurality of resonator portions. At least one of the paired reflectors 4, 5 has a curved-surface mirror. The laser medium 6 is interposed between the paired reflectors 4, 5. Laser beams 8 emitted from the point laser sources 1, 2 are passed through one of the paired reflectors 4, 5 and irradiated as pumping lights on one end face of the laser medium 6. The resonators include the pair of reflectors, the laser sources 1, 2 and a plurality of thermal lenses. The thermal lenses are formed within the laser medium 6. The resonators produce output laser beam to produce from the other end face of the laser medium 6 through other one of the reflector 5.

Abstract: A dispersive laser pulse stretcher and compressor comprises a stretcher portion and a compressor portion. A first mirror, a second mirror, a third mirror, a first grating, a first lens, and a first vertical retroreflector block comprise the stretcher portion. A fourth mirror, a second grating, a horizontal retroreflector, and a second vertical retroreflector block preferably comprise the compressor portion. The input beams for the stretcher and compressor are preferably parallel beams. The present invention also positions the first grating of the stretcher in a parallel plane with the second grating of the compressor.

Abstract: Yb.sup.3+ and Nd.sup.3+ doped Sr.sub.5 (VO.sub.4).sub.3 F crystals serve as useful infrared laser media that exhibit low thresholds of oscillation and high slope efficiencies, and can be grown with high optical quality. These laser media possess unusually high absorption and emission cross sections, which provide the crystals with the ability to generate greater gain for a given amount of pump power. Many related crystals such as Sr.sub.5 (VO.sub.4).sub.3 F crystals doped with other rare earths, transition metals, or actinides, as well as the many structural analogs of Sr.sub.5 (VO.sub.4).sub.3 F, where the Sr.sup.2+ and F.sup.- ions are replaced by related chemical species, have similar properties.

Abstract: A semiconductor laser device includes a substrate; a double hetero structure having an n-type cladding layer, an active layer, and a p-type cladding layer, which is formed on an upper face of the substrate; and electrodes formed on a lower face of the substrate and on an upper face of the double hetero structure, wherein the double hetero structure further includes a p-type hetero-barrier layer formed between the p-type cladding layer and the active layer, which is strained by compression due to a lattice mismatch.

Abstract: An anode and a cathode in a laser are spaced in a first direction. A voltage difference between these members produces an electrical discharge which ionizes gases in the laser to react chemically and produce coherent radiation. First and second tubes made from a dielectric material are spaced in the laser in a second direction transverse (preferably perpendicular) to the first direction. The anode, the cathode and the tubes extend through the laser in a direction transverse (preferably perpendicular) to the first and second directions. The tubes are preferably at least a 99.9% pure polycrystalline aluminum oxide ceramic with traces of other metallic elements than aluminum. Bushings made from a material homogeneous (preferably identical) to the tube material are integral with the tube near the opposite tube ends. First electrical conductors extend through the tubes.

Abstract: A thin absorbing film is bonded onto at least certain surfaces of a solid state laser gain medium. An absorbing metal-dielectric multilayer film is optimized for a broad range of incidence angles, and is resistant to the corrosive/erosive effects of a coolant such as water, used in the forced convection cooling of the film. Parasitic oscillations hamper the operation of solid state lasers by causing the decay of stored energy to amplified rays trapped within the gain medium by total and partial internal reflections off the gain medium facets. Zigzag lasers intended for high average power operation require the ASE absorber.

Abstract: A vertical-cavity, surface-emitting semiconductor diode laser having a monolithic and planar surface and having lateral anisotropy in order to control the polarization of the emitted beam of light. The diode laser includes a body of a semiconductor material having an active region therein which is adapted to generate radiation and emit the radiation from a surface of the body, and a separate reflecting mirror at opposite sides of the active region with at least one of the mirrors being partially transparent to the generated light to allow the light generated in the active region to be emitted therethrough. The anisotropy may be provided by utilizing anisotropy in the atomic or molecular structure of the materials forming the laser, or by anisotropic patterning or deliberate offset alignment in processing of the laser or through anisotropic structures in the laser cavity to control the polarization of the emitted beam.

Abstract: A metal vapor laser is disclosed that recycles condensed metal located at the terminal ends of a plasma tube back toward the center of the tube. A pair of arcuate wedges are incorporated on the bottom of the plasma tube near the terminal ends. The wedges slope downward toward the center so that condensed metal may be transported under the force of gravity away from the terminal ends. The wedges are curved to fit the plasma tube to thereby avoid forming any gaps within the tube interior.

Abstract: A phase-locked laser array comprising a plurality of element regions for passing electric current into an active layer; and inter-element regions formed between the element regions. Each of the inter-element regions is so formed as to have two regions, i.e. a non-diffusion region at the center thereof and a diffusion regions disposed on both sides thereof, thereby rendering the refractive index in the non-diffusion region higher than that in the diffusion regions. The method of manufacturing the phase-locked laser array which is characterized by including a step growing an optical waveguide layer of superlattice on a portion of a second clad layer while diffusing impurities doped in the second clad layer into said optical waveguide layer, thereby forming a diffusion regions on both sides of the inter-element region.