Abstract: A pulse laser which outputs a pulsed laser beam, comprises a delaying means which delays the timing of shift from off to on of a laser output timing signal which is turned on during the output period of the pulse laser for the time required to output one laser pulse and an average output measuring means which measures the average output of the pulse laser while the laser output timing signal is on. The average output of the pulse laser is accurately measured by eliminating the influence of giant pulses.

Abstract: A laser having an electrode assembly which reduces the formation of glow-to-arc transitions. The electrode assembly of the present invention includes a cathode sub-assembly placed in opposition to an anode sub-assembly, with a main discharge region defined between the two. The cathode assembly includes an electrode in electrical contact with a cathode plate, the latter of which is formed from negative temperature coefficient of resistivity (NTC) material. The anode assembly includes an anode to which is mounted at least one structural member, at a position away from the main discharge region. This structural member is separated from the edges of the cathode plate by a gap, across which arcs may form.

Abstract: A continuous wave photolytic iodine laser has a gain cell for receiving a continuous supply of gaseous fuel. The gain cell is connected to laser beam transfer optics, a laser resonator for shaping a laser beam, and a lamp. The lamp is driven by a microwave subsystem such that a laser gain medium is pumped through the gain cell. The continuous wave photolytic iodine laser of the present invention incorporates a closed loop fuel system for presenting gaseous fuel to the gain cell at a rate sufficient to sweep any lasing by-products out of the gain cell, thereby preventing quenching of the lasing process. The fuel system also includes a condenser for converting the gaseous fuel to a liquid after it has passed through the gain cell, a scrubber for removing the by-products of the lasing process from the fuel, and an evaporator for converting the recycled liquefied fuel back to a gas. The closed loop fuel system also includes a pump for pressurizing and transporting the liquefied fuel.

Abstract: A laser device which is tunable within the mid-IR range is provided. The device includes a thin etalon, formed as an uncoated plane-parallel plate of high refractive index material, which is transparent for both pump and resonant (signal, idler or both) radiation, for coupling the pump beam to the cavity of an optical parametric oscillator. Such an optical element does not require thin film optical coatings and inherently possesses a high optical damage threshold. Furthermore, high reflectivity at the pump wavelength and high transmittance for oscillating radiations are provided, by orienting the etalon at the Brewster angle. Examples of such materials include silicon and germanium, which are transparent at wavelengths longer than approximately 1 .mu.m and 2 .mu.m, respectively, and have refractive indices of n=3.4 and n=4.0, respectively.

Abstract: A connector adapter and dust cover therefor are pivotably connected by means of a pivot pin on the adapter and pivot arms on the dust cover whose distal ends engage the pivot pin. The pivot pin has a cam member located intermediate its ends, and the dust cover has a spring arm between the pivot arms whose distal end engages the cam member. In the closed position, the distal end of the spring arm engages the cam below its high point. In the fully open position, the distal end of the spring arm engages the cam beyond its high point. In both positions, the spring arm bears against the cam to resist dislodgment of the dust cover from either position.

Abstract: A solid state laser has an elongate slab of lasing material having a rectangular cross section with the lower face of the slab contacting a slab mount which is of a high thermal conductivity material. Energy to drive the lasing medium is provided by a flash lamp. Upper and lower faces of the slab are polished to an optically smooth finish so that light is able to propagate in a generally axial direction through the slab. Side faces of the slab are polished and then re-roughened to provide a finish with a surface damage zone comparable in depth to the wavelength of the lasing emission. For a lasing wavelength of one micrometer, the depth of surface damage is in the region of one micrometer.

Abstract: A multiposition optical connector 2 and a mating header 4 are disclosed. The connector includes a plurality of ferrules 10 for terminating individual plastic optical fiber cables 6. An alignment fixture 100 is used to precisely align each ferrule relative to the other ferrules and relative to peripheral mating surface protrusions 52 on a molded alignment plate 12. The ferrules are ultrasonically bonded to the alignment plate. True positioning for multiple fibers located in the multiposition connector relative to active optoelectronic devices 90 located in the header can be achieved when the connector and the header are mated. A previously assembled harness assembly using the optical connector 2 and a hybrid electrical and optical connector 202 is suited for use in making multiple connections to products, such as automobiles, in which the final assembly is completed in an assembly line.

Abstract: The present invention provides an optical fiber cable terminal structure which includes a cap member that eliminates any danger of cutting of a reinforcing member even when external forces are applied to the optical fiber cable, and which allow easy re-engagement of an engaging member and an outer covering of the optical fiber cable. The optical fiber cable terminal structure includes a substantially cylindrical cap member (10). The cap member (10) has a cavity (50) inside, and further has a curved surface (35a) on an end surface (35). Curved surface (35a) provides a smooth continuation between an inside surface (36) and an outside surface (32). Reinforcing member (170) of optical fiber cable (100), which is passed through the cavity (50) and folded back along the curved surface (35a), can be fastened to the outer surface (32) by the press-fitting of a sleeve member (90) onto outside surface (32).

Abstract: A light emitting element driving circuit which drives a light emitting element including the following. A drive transistor is coupled to a power supply voltage and is provided on a side of an anode of the light emitting element. The drive transistor receives an input signal and supplies the light emitting element with a pulse current and a bias current. A cathode of the light emitting element is connected to a lower potential than the power supply voltage.

Abstract: A solid state laser, especially a solid state laser pumped by laser diodes (3b, 3c) comprises a polarizing beam splitter (5) to couple out from the resonant cavity some part (11) of the radiation energy. An electro-optic modulator (Pockels' cell) (4) serving as couple-out modulator is adjusted such that the ratio of the pulse energy of the laser beam pulses (10) emitted to the coupled-out part (11) of the radiation energy is variable and thus the pulse energy is adjustable by keeping the pulse duration constant.

Abstract: A semiconductor light-emitting device comprising a substrate having thereon: a first conductive type first clad layer; an active layer; a second conductive type first clad layer having a stripe region to which a current is injected and the remaining region; a ridge portion comprising: a ridge-shape second conductive type second clad layer formed on the stripe region of the second conductive type first clad layer; a second conductive type contact layer formed on the ridge-shape second conductive type second clad layer; and a protective film formed on the second conductive type first clad layer to cover the remaining region thereof, wherein a part of the second conductive type second clad layer is formed on said protective film, or wherein said contact layer is formed on a substantially whole surface area of said second conductive type second clad layer, or wherein said ridge portion has no protective layer on the side surface thereof.

Abstract: A quantum cascade (QC) laser has a multilayer core region comprising alternating layers of a first and a second semiconductor material, with lattice constants a.sub.1 and a.sub.2, respectively. The first material is selected such that a.sub.1 >a.sub.0, where a, is the lattice constant of the substrate (typically InP), and the second material is selected such that a.sub.2 >a.sub.0. The materials are also selected such that the conduction band discontinuity .DELTA.E.sub.c between the first and second materials is greater than 520 meV in absolute value. The multilayer core comprises a multiplicity of essentially identical multilayer repeat units. The layer thicknesses and materials of the repeat units are selected to substantially provide strain compensation over a repeat unit. QC lasers according to this invention preferably comprise a distributed feedback feature, (e.g.

Abstract: A method for laser shock peening a target surface generates laser pulses from a cavity dumping oscillator having an optically-pumped laser and directs the pulses against the target. A first technique uses pulses having rectangular cross section. A second technique passes each generated pulse two or more times through the same optical amplifier before directing the pulse against the target. A third technique drives the laser with a time pulse of electric current having a rectangular shape. A reflective laser beam homogenizer uses two abutting mirrors to split a laser beam into two equal halves and then uses an odd number of additional mirrors to reflect each half first behind and then to the opposite one of the two mirrors to be reflected back as a beam having interchanged halves.

Abstract: A laser oscillation apparatus includes: a laser cavity unit for generating laser light by being provided a voltage and optically amplifying the generated light by means of a pair of mirrors; and a DC power source for supplying the voltage required for generating the laser light to a pair of discharge electrodes of the cavity unit. Each of a cathode and an anode of the DC power source is grounded via a grounding resistor.

Abstract: An optical fiber connector is disclosed for terminating an optical cable which has a plastic core and a surrounding jacket. The connector includes a body member which has a central bore extending therethrough within which is a longitudinally extending internally threaded portion dimensioned to grip the plastic jacket when the cable is screwed into the body member. The bore has a tapered section extending from the threaded portion to a cable entrant end of the body to facilitate insertion of an optical cable into the body.

Abstract: The length of the tail which results in an optical output from a laser diode after the laser diode is no longer being driven is reduced or eliminated by a laser diode driver with a tail eliminator. More specifically, the laser diode driver includes an energy drainage path that is activated when packet communication is over. In one embodiment of invention, the terminals of the laser diode are short-circuited to provide the energy drainage path. In another embodiment of the invention, the laser diode is reverse biased, so that charges stored in the laser diode are combined with charges which are provided thereto. Advantageously, the tail emission is substantially eliminated.

Abstract: The invention describes a method of single-transverse-mode generation for waveguide lasers of various kinds having a large cross section of their active core and thus providing a possibility of efficient pump of the active core region. This results in a laser beam with enhanced power and high spatial quality for high efficiency coupling to standard single-mode optical fiber networks. It is found that a multimode waveguide having a central dip of special shape in the refractive index profile of its core is able to guide a higher order mode with sharp central peak of its field carrying the considerable part on the mode energy and whose width is well compatible with the width of the fundamental mode of standard single-mode fibers. The useful properties of this higher order mode can be employed to provide the single-transverse-mode regime of generation in optical fiber lasers, integrated optical micro-lasers and various semiconductor laser sources.

Abstract: A semiconductor laser includes a first conductivity type semiconductor substrate having a gain region and a spot size changing region adjacent each other; a first conductivity type lower cladding layer disposed on the substrate; an active layer disposed on the lower cladding layer and having a thickness which is uniform in the gain region and gradually decreases in the spot size changing region with distance from the gain region; a second conductivity type upper cladding layer disposed on the active layer and having a stripe-shaped ridge, the ridge extending along the gain region and the spot size changing region; a first electrode disposed on the ridge of the upper cladding layer; and a second electrode disposed on a rear surface of the substrate. Current flow is concentrated in the ridge of the upper cladding layer.

Abstract: An optical fiber (20) includes a silica-based core (22) which is operative to transmit light and is surrounded by a silica-based cladding (24) having a lower index of refraction than the core (22). A primary coating (26) surrounds cladding (24), and a secondary coating (28) surrounds primary coating (26). Optical fiber ribbon (40) includes a ribbon matrix material (42) which surrounds a plurality of optical fibers (20). Primary coating (26) comprises a photinitiator which has a peak absorbance in a relatively short wavelength UV spectrum. Secondary coating (28) comprises a photinitiator which has a peak absorbance in a relatively long wavelength UV spectrum.

Abstract: Autophase stability is provided for a traveling wave device (TWD) electron beam for amplifying an RF electromagnetic wave in walls defining a waveguide for said electromagnetic wave. An off-axis electron beam is generated at a selected energy and has an energy noise inherently arising from electron gun. The off-axis electron beam is introduced into the waveguide. The off-axis electron beam is introduced into the waveguide at a second radius. The waveguide structure is designed to obtain a selected detuning of the electron beam. The off-axis electron beam has a velocity and the second radius to place the electron beam at a selected distance from the walls defining the waveguide, wherein changes in a density of the electron beam due to the RF electromagnetic wave are independent of the energy of the electron beam to provide a concomitant stable operating regime relative to the energy noise.