Abstract: A passively mode-locked laser (110) is disclosed that includes a resonant cavity (112, 114) having a gain medium (116) therein. A transmissive element (116), which may be the gain medium, is also located in the cavity and is formed from a material which varies the two-dimensional, lateral spatial profile of the beam with respect to intensity due to the Kerr effect. The resonator is arranged such that the round trip gain of the system increases with respect to the intensity of the beam so that mode-locking operation can be achieved. In one approach, the variation in the spatial profile is used to increase the extraction of energy from the gain medium. In another approach, the variation in spatial profile which occurs with an increase inintensity is used to decrease the loss in the system so that pulse operation is favored.

Abstract: Free electron laser.This laser includes a source (2) of electrons, means (4) for accelerating the electrons which supply a beam of electrons, a ring (6) for storing this beam and comprising at least one rectilinear section, magnetic means (22) provided to create a closed magnetic configuration having one first component mainly directed parallel to the circulating beam of electrons and which enables this beam to be contained, and one second component suitable for compensating the drift of the electrons transversally to the axis of the beam of electrons, and at least one magnetic wiggler (10) placed at the level of the rectilinear section and which is traversed by the beam of electrons. Application for fusion controlled by magnetic containment.

Abstract: To provide more economical excitation of a high-power laser comprising a resonator having mirrors arranged in spaced, opposite relation to each other in the direction of a resonator axis and a beam path extending in both the direction of the resonator axis and a transverse direction perpendicular thereto, a gas-discharge volume permeated by the beam path and containing laser gas, and two facing wall surfaces extending substantially parallel to the resonator axis and to the transverse direction and enclosing between them and thereby delimiting the gas-discharge volume, it is propsoed that at least one wall surface be formed by a dielectric wall, that a microwave resonance structure separate from the laser gas in the gas-discharge volume be placed on the dielectric wall and have an opening facing the dielectric wall and bring about in an area of volume of the gas-discharge volume opposite the opening a microwave excitation of the laser gas, and that microwaves be introducible into the microwave resonance struct

Abstract: A minilaser device exhibiting both laser and non-linear optical effects. The device includes a single laser crystal bar of NYAB which inhibits non-linear characteristics and serves as a self-frequency-doubling crystal having the laser and non-linear optical effects, and a pumping source for the device to generate laser light.

Abstract: In a pulse power supply circuit, first and second charging capacitors are connected in series with a discharge device. First and second gas-filled control switching elements, connected in parallel with each other, are respectively connected in series with the first and second charging capacitors. First and second pulse power sources are respectively connected in parallel with the first and second control switching elements and also respectively connected in series with the first and second charging capacitors so as to charge the capacitors alternately. A control circuit controls the first and second control switching elements so that the switching elements alternately and repeatedly at substantially equal time intervals.

Abstract: To provide more economical excitation of the laser gas in a waveguide laser comprising a resonator having a resonator axis, an optical waveguide extending with a waveguide longitudinal direction essentially in the direction of the resonator axis and a gas-discharge volume located between the optical waveguide surfaces and containing a laser gas, it is proposed that a microwave source be provided, that an overcoupling structure separate from the laser gas in the gas-discharge volume be arranged on a side of one of the optical waveguide surfaces opposite the gas-discharge volume, the overcoupling structure being connected via a waveguide to a microwave source, extending in an overcoupling direction parallel to the optical waveguide surface and bringing about in a strip region in the gas-discharge volume along the overcoupling direction a substantially constant coupling-in of the microwave power.

Abstract: The aim is to provide a new power laser configuration enabling the delivery of a beam of high spatial quality with an optimum efficiency of extraction of energy. It can be applied, more particularly, to Q-switch solid-state lasers, in doing away with recourse to specific elements for compensation of aberrations. The structure of emission of a power pulsed laser signal, of the type comprising, firstly, an oscillator stage with low-level output beam and, secondly, a power amplifier stage, is characterized in that the power amplifier stage is formed by a laser amplifier that produces a pump beam cooperating with distinct means for energy transfer without phase transfer from said pump beam towards said low-level beam coming from the oscillator.

Abstract: A process for increasing the efficiency of a chemical process yielding stimulated emission of visible radiation via fast near resonant intermolecular energy transfer comprising the steps of reacting a first metal vapor with a reactant to form a metastable state of a metal oxide or metal halide and transferring the energy from the metastable state to receptor metal atoms by means of near resonant energy transfer to form electronically excited receptor metal atoms in an inverted configuration by using highly volatile precursor compounds to provide the receptor metal atoms, by introducing a quenchant gas during the energy transfer step, or by introducing CO.sub.2 laser photons during the energy transfer step.

Abstract: An electronics controller for controlling the power supply of a laser operating in a pulse mode is disclosed. The power supply is of the type having a resonant DC converter, charging a capacitive storage means with an inverter stage driving the laser discharge tube. The current supplied to the laser discharge tube is monitored. In addition, the voltage of the capacitive storage means is also measured. Set points for the current, the voltage, and on/off are provided to the electronics controller as the comparison points for the controller. Based upon the voltage and current detected, and the set points provided, the controller controls the on/off of the converter and its frequency, and the on/off of the inverter.

Abstract: A laser system is disclosed wherein a solid state gain medium (30) is longitudinally pumped with the beam (40) from another laser (42). The laser is configured with an optically stable resonator while at the same time matching the shape of the pump beam to the shape of the cavity beam in the gain medium. Optimum matching is achieved by taking into consideration thermal lens effects in the gain medium resulting from absorption of the pump beam.

Abstract: An Er-doped optical fiber laser device adapted for pumping by light from a pumping light source in an erbium (Er)-doped optical fiber which enters a single mode at the wavelength of amplified light. In accordance with the present invention, the Er-doped optical fiber is further doped with at least one of holmium (Ho), thulium (Tm) and dysprosium (Dy). The pumping light source emits light in a 1.1 to 1.4 .mu.m band. The output light from the pumping light source and signal light incident to the Er-doped optical fiber are combined by a combining optical fiber coupler.

Abstract: Continuous laser action is sustained by a new pumping mechanism which relies exclusively on cooperative electronic transitions of coupled atoms or ions in solids. The laser depends on energy-sharing interactions between a trio of atoms in gases or active dopants in solid laser media to create the population inversion needed for amplification of light. In one specific embodiment, the laser crystal is formed of calcium fluoride doped heavily with trivalent erbium, and is provided with reflective coatings on respective first and second surfaces. A pumping energy is supplied whereby a three atoms are elevated to an initial excited state. Subsequently, two of the atoms lose energy so as to assume a ground state, the energy released thereby being made available to excite the third atom to a still higher quantum energy state. Thus, a cooperative energy interaction between the trio of atoms results in the double excitation of one of the atoms above the initial excitation state.

Abstract: A method of converting the laser radiation of a pump laser into another wavelength range by stimulated Raman scattering in which the laser radiation of the pump laser is conducted through a Raman medium, thus generating Stokes radiation in the other wavelength range, and an arrangement for implementing the method. The laser radiation from the pump laser leaving the Raman medium and the generating Stokes radiation are fed together to an amplifier for the laser radiation of the pump laser, and the thus amplified laser radiation of the pump laser is conducted together with the accompanying Stokes radiation through a further Raman medium for conversion of the amplified laser radiation of the pump laser into Stokes radiation.

Abstract: A solid-state laser of improved amplitude stability is obtained by substantially eliminating spatial hole burning in the lasant material and maintaining the optical cavity of the laser at a temperature which results in substantially noise-free generation of output radiation.

Abstract: A laser incorporating a laser medium disposed within a laser cavity and a pumping arrangement for selectively applying excitation energy to said laser medium. The laser medium contains upconverting material of the type which allows for the exchange of energy between electrons of the lasing ions at a given energy state below the meta-stable initial lasing state so that some of said exchanging electrons are upconverted to energy states at or above the meta-stable initial lasing state. The pumping arrangement applies energy of suitable wavelength and intensity for elevating electrons from energy levels below the given state to that state in sufficient numbers to support substantial upconversion and the resulting lasing.

Abstract: A dye of the DCM family, [2-methyl-6-[2-(1,2,3,4-tetrahydro-1-methyl-6-quinolinyl)ethenyl]-4H-pyran -4-ylidene]-propanedinitrile, dissolved in 2-phenoxyethanol, is non-mutagenic, stable and efficient, particularly in a pumped continuous wave laser system.

Abstract: An improved pumping arrangement for use in a face pumped or edge pumped slab laser, this arrangement comprising upper and lower housing members able to be removably secured together in an operational relationship. The lower housing member has in a central portion thereof, a body of solid state laser host material, with the laser host material typically having a rectangular cross-section with top and bottom surfaces, opposing side surfaces, and opposing end faces. The lower housing member also is configured to have a pair of spaces running the length of the laser host material. The upper housing member has on its underside, a pair of parallel flashlamps set a distance apart. The lower housing member is able to receive the upper housing member in an interfitted, operative relationship, in which the flashlamps are received in the respective spaces alongside the body of solid state laser host material.

Abstract: An apparatus and method for pumping a gas laser, wherein a field emitter is sed to emit electrons into the gas to effect laser pumping. The low energy electrons emitted by field emitters, and the fine controllability of electron energy permitted by field emitters, enables one to effect population inversion of the laser gas, without ionizing the gas, or causing electrical breakdown.

Abstract: A package for the components of a laser device that includes an elongated laser medium, a pump source adjacent to one side of the laser medium and laser mirrors positioned in alignment with the optical axis of the laser medium, the package including a planar heat conducting structure including a base member with a cavity formed on one side and a platform at an intermediate location for supporting the laser elements, and a closure member for closing the cavity around the laser elements, and a multi-conductor connection cable mounted in the package having connections to the pump source and to a source of electrical energy.

Abstract: A semiconductor laser apparatus includes a semiconductor laser for emitting a light beam. The semiconductor laser has, as an external cavity, a quadruple light wave mixing optical phase conjugate element for inverting a spatial phase of an incident light beam. The apparatus further includes a pair of pump light sources which are arranged such that a superimposed portion of spectra of wavelengths of three light beams including two pump light beams emitted from the pair of pump light sources and entering into the optical phase conjugate element and another light beam emitted from the semiconductor laser is narrower than the spectral width of wavelengths of each of the three light beams. This enables the laser apparatus to generate an oscillating output wavelength of extremely narrow spectral width.

Abstract: As a beam converger, one having reflective surfaces including partial cylindrical curved surfaces and partial plain surfaces, which surround laser rod and pump lamp plane-parallelly and substantially uniformly in the axial direction thereof, is adopted, so as to make a high beam converging property in the case of adoption of an elliptic cylinder moderate. The axes of the pump lamp and/or the laser rod are shifted to positions closer to the partial cylindrical curved surfaces than the center lines of the partial cylindrical curved surfaces, so as to increase energy of light exciting the laser rod by the pump lamp, thus improving the efficiency. A laser system obtained by combining a resonant type laser device comprising two laser rods and one or two pump lamps with a prism having a regular equilateral triangle shape in cross section, highly contributes to the compactness and simplification of the laser system.

Abstract: An Nd/YAG slab laser (1) is pumped by laser diodes (2) placed at a distance from the laser slab. Reflectors (7) convey the light from the diodes to the slab. The distance is such that the density of such light is made uniform. A cooling fluid flows along a compartment (5) between the diodes and the slab. The invention is applicable to producing infrared coherent light.

Abstract: An excimer laser including a discharge chamber containing a mixture of halogen, rare gas and buffer gas uses two gas sources to replenish the halogen in the discharge chamber while maintaining the concentrations of all the gases at the optimum levels. One of the gas sources, source A, contains a mixture of the rare gas and the buffer gas in optimum concentrations. The other gas source, source B, contains both the rare gas and the buffer gas, in optimum relative concentrations, and also the halogen, in a concentration which is greater than optimum. As the laser operates and the gain of the laser decreases due to halogen depletion, gas from source B is injected into the discharge chamber to raise the halogen concentration. Gas is then released from the chamber to reduce the chamber pressure to the original level.

Abstract: A resonantly photo-pumped X-ray laser (10) that enhances the gain of seve laser lines that also lase because of collisional excitations and recombination processes, is described.The laser comprises an aluminum (12) and erbium (14) foil combination (16) that is driven by two beams (18, 20) of intense line focused (22, 24) optical laser radiation. Ground state nickel-like erbium ions (34) are resonantly photo-pumped by line emission from hydrogen-like aluminum ions (32).

Abstract: A metallic vapor laser apparatus comprises a discharge tube, a first pulse circuit (200) for generating a first pulse voltage for causing laser oscillation and a second pulse conduit (16) disposed separately from the first pulse circuit and generating a second pulse voltage delayed from the generation of the first pulse voltage by a predetermined time. The metallic vapor laser apparatus is constructed such that, after the first pulse voltage is applied to the discharge tube, the second pulse voltage is applied to the discharge tube and an output voltage of the second pulse circuit (16) is less than an output voltage of the first pulse circuit (200).

Abstract: A low-pressure mercury resonance radiation source includes a discharge lamp containing mercury vapor and producing broad band radiation directly emitted from the mercury vapor through excitation of same by electric discharge, and a resonance cell containing mercury vapor and disposed adjacent the discharge lamp for absorbing the broad band radiation and reemitting narrow band mercury resonance radiation. The pressure of the mercury vapor within the resonance cell is controlled to a first predetermined value by controlling the temperature of a first mercury sump arranged within the resonance cell, and the pressure of the mercury vapor within the discharge lamp is controlled to a second predetermined value, preferably by controlling the temperature of a second mercury sump arranged in a side tube communicating with the discharge lamp.

Abstract: A room-temperature, laser-pumped, Q-switched, thulium-doped, solid state laser for producing pulses of laser emission at substantially 2 microns is disclosed. In a preferred embodiment, the laser comprises: a laser cavity defined by first and second reflective elements opposing each other on a common axis to form a reflective path therebetween; a laser crystal disposed in the laser cavity, the laser crystal having a host material doped with an amount of thulium activator ions sufficient to produce a laser emission at substantially 2 microns from the .sup.3 F.sub.4 to .sup.3 H.sub.

Abstract: An optical fiber laser includes a single-mode optical fiber doped with a lasing material such as Neodymium. The optical fiber is pumped with a pump optical signal having a pump wavelength selected to cause spontaneous emission of an optical signal at a second wavelength different from the pump wavelength. The optical fiber is formed into a laser cavity such as by including a suitable reflector at each of the two ends of a suitable length of the optical fiber so that the emitted optical signal oscillates therein. One of the reflectors has a reflectivity at the wavelength of the emitted light so that most (e.g., approximately 95%) of the emitted light is reflected back into the laser cavity and a smaller portion (e.g, approximately 5%) is transmitted through the mirror as a laser output signal. Alternatively, the optical fiber can be formed into a ring laser structure using an optical coupler that couples a substantial portion (e.g.

Abstract: In order to so improve a microwave-pumped, high-pressure, gas-discharge laser, in particular, excimer laser, with an optical resonator, with a resonator gas volume arranged therein and extending along an optical axis thereof, with a microwave coupling structure enclosing the resonator gas volume within it and with a microwave generator connected to the microwave coupling structure, that a wall breakdown is substantially suppressed, it is proposed that a central area with an electric field intensity lying above a threshold value for a high-pressure gas discharge be disposed within the resonator gas volume in a transverse direction to the optical axis and be adjoined on both sides thereof by outer areas with a field intensity lying below the threshold value for the high-pressure gas discharge.

Abstract: A conductively cooled, optically diode-pumped slab laser comprises a slab laser host 1 having transparent, thermally conductive heat sink means 2 bonded to its pump faces. Semiconductor lasers or light emitting diodes 3 are mounted on the heat sink means for generating pumplight which is transmitted through the heat sink means 2 into laser host 1 to cause lasing. Heat flow within the laser host 1 is substantially bi-directional, thereby minimizing optically harmful thermal distortion of the host. The apparatus can function as laser amplifier, laser oscillator or combined oscillator/amplifier.

Abstract: In a laser, the laser gain member is optically pumped by a semiconductive source of pumping radiation having an elongated output beam aperture such as that provided by a single-wide stripe diode or diode array. The elongated beam of optical pumping radiation is twice reflected from a concave surface at non-normal angles of incidence and then focused onto the laser gain material for pumping same. The reflections serve to differentially focus rays diverging in the vertical plane from rays diverging in the horizontal plane to shape the pumping beam for improved pumping efficiency in the pumped mode volume of the laser gain material. In a preferred embodiment, a magnifying lens is disposed inbetween the source and the reflectors for decreasing the divergence of the pumping beam.

Abstract: A solid-state laser comprises a columnar laser rod having a central longitudinal axis, a total reflection mirror arranged coaxially of the laser rod in facing relation to one end face thereof, and a half mirror arranged coaxially of the laser rod in facing relation to the other end face thereof. The pumping light is emitted from a plurality of laser diodes arranged in an array laterally spaced from the laser rod in parallel thereto. A cylindrical lens arranged between the laser rod and the array of laser diodes serves to focus the emitted pumping light on the central longitudinal axis of the laser rod. The active substance in the laser rod is excited by the thus focused pumping light to generate a laser beam axially of the laser rod.

Abstract: An optically pumped solid-state laser oscillating device which includes an optical resonator for outputting a laser beam of a predetermined wavelength. The optical resonator has a predetermined optical absorption band and is excited in response to a semiconductor laser beam having a wavelength falling within the optical absorption band. A plurality of excitation light sources are provided for emitting a plurality of semiconductor laser beams having different wavelengths and applying those laser beams to the optical resonator. At least one of the plurality of the semiconductor laser beams has a wavelength falling within the predetermined optical absorption band regardless of the change of an ambient temperature. Hence, a stable laser output is obtainable regardless of the change of the ambient temperature without need for employment of a complicated temperature controlling mechanism.

Abstract: A superfluorescent broadband fiber laser source comprises a fiber doped with laser material coupled to a multiplexing coupler. In the preferred embodiment, a source of pumping illumination provides pumping light to the doped fiber, and the coupler is adjusted to have a 0% coupling efficiency at the wavelength of the source. The pumping light is sufficiently intense to produce amplified spontaneous emission within the doped fiber, and gives rise to a forward signal and a backward signal. One of the superfluorescent signals is reflected back to the doped fiber by a reflector cemented to one end of the doped fiber or to one end of another fiber through the coupling function of the coupler. The coupler is adjusted to provide complete coupling at the frequency of the lasing light. The temperature dependence of the coupler can be selected to reduce or cancel the temperature dependence of the superfluorescent signal. Other arrangements utilizing the multiplexing properties of the coupler are also described.

Abstract: A xenon short arc discharge lamp has a lamp bulb (1) of quartz glass, into which two rod-shaped electrodes (4, 5) protrude, the spacing of which is shorter than the diameter of the shaft (8) of the cathode (5); the cathode (5) is provided with a conical, obtuse tip (9). By doping with a metal halide, such as thallium iodide, the spectral radiant intensity per unit area in the plasma zone immediately in front of the cathode (5) is increased substantially compared with an undoped xenon short arc discharge lamp, and as a result of a flow-controlled tungsten-halogen cycle process, a stabilized cathode spot operation is attained, and the inner wall of the lamp bulb (1) remains free of tungsten deposits.

Abstract: The generation of soft x-ray and/or extreme untraviolet laser radiation is accomplished in a capillary plasma generated by a fast discharge. The method yields laser action at short wavelengths in a discharge created plasma having a large length-to-diameter ratio.

Abstract: A laser oscillator device applies a high-frequency voltage to a plurality of discharge regions (1a, 1b) through a dielectric to produce a high-frequency discharge for laser pumping. The laser oscillator device includes high-frequency power supplies (26a, 26b) for converting a DC power supply into high-frequency power supply outputs, output transformers (22a, 22b) for boosting the high-frequency power supply outputs and transmitting high-frequency electric power to the discharge regions, the output transformers having secondary windings with grounded midpoints, and current detectors (CT1a, CT1b) for detecting currents flowing through discharge tubes. Output currents of the high-frequency power supplies are controlled by feeding back the detected currents. Since the detected currents are not affected by mutual currents between electrodes, alarm conditions due to uncontrollable operation of a feedback loop and damage of parts are prevented from occurring, and stable current control is achieved.

Abstract: A laser system in which the laser medium is a single crystal of Cr.sub.3+ :Mg.sub.2 SiO.sub.4 is disclosed. In one embodiment, the system comprises a single crystal of chromium doped forsterite and a cavity which includes a pair of 30 cm. radius mirror having high transmission at 543 nm (the pump wavelength) and high reflectivity in the 1150-1350 nm range. Room temperature vibronic pulsed laser action is obtained with this cavity. Laser action has been observed at 1235 nm and a bandwidth of 25 nm. The wavelength range is suitable for transmission through optical fibers and is useful in laser ranging and remote sensing. Because of the ultrawide fluorescence bandwidth and a 15 fluoroescence lifetime the system is suitable for high intensity, tunable, cw, Q switched mode locked operation. In the mode locked operation pulses as short as 10-500 femtosecond may be generated. A number of different embodiments of the invention are described.

Abstract: A laser system operable in both a lead bonding mode and a lead severing mode. When in the lead bonding mode, the light-amplifying medium (38) of the laser is optically pumped by a lamp (45) to produce laser pulses within the laser cavity (36). The power supply (56) is rapidly switched to provide the bonding pulses (L.sub.b) at a high repetition rate. A Q-switch (46) is disposed within the cavity (36) to shape the laser output pulses (L.sub.b) with a leading power spike (S.sub.b) that is suitable for reducing the reflectivity of the lead (20) surface, thereby facilitating maximum absorption of the laser energy for the bonding operation. When in the severing mode, the light-amplifying medium (38) is continuously pumped and the Q-switch (46) is repetitively switched at a rate high enough to generate laser pulses (L.sub.s) suitable for severing the leads (20) without heating adjacent portions of the leads (20).

Abstract: A radioactive light source consists of a vacuum tight envelope filled with a mixture of a radioactive gas such as tritium with one or more other gases which luminesce when excited by the emission from the radioactive gas without the aid or requirement of any externally applied energy source, such as electrical power. This luminescence may be viewed through the wall of the chamber which may be transparent. Alternatively, all or a part of the luminescence may be converted to a different region of the spectrum by a suitable phosphor layer coated on the wall of the envelope.

Abstract: Accelerator for coherent bosons. Helium clusters are formed by expansion of helium gas through a nozzle into a low pressure chamber. The clusters contain coherent helium particles. Laser light is shone onto the clusters to cause the coherent helium atoms in the clusters to be accelerated by impact of the coherent light from the laser thereon, so that the helium atoms form a high energy coherent beam.

Abstract: In a gas laser excited with pulsed microwave energy, a running gas discharge is generated in a waveguide, this discharge placing the gas in its excited condition, and expiring after migrating through the waveguide. The microwave energy is supplied at one end of the waveguide, and a short-circuit element is disposed at the other end of the waveguide, with an igniter attached in proximity to the short-circuit element so that the gas discharge, and thus the excitation of the laser gas always begins at the end of the waveguide at which the short-circuit element is disposed. This structure is especially suited for CO.sub.2 lasers.

Abstract: A multiple crystal, single pumping cavity laser system comprises an optical pumping cavity, several laser crystal rods disposed in the cavity and having differently sized diameters and with their axes parallel, an optical coupling device for coupling the rods in a chain of increasing diametrical size, an optical pumping source for providing an optimum pumping level for the largest rod, and attenuators for all but the largest sized rod for attenuating the energy absorbed by the smaller rods. Since all of the laser rods are disposed and pumped in a single pumping capacity, only a single pumping source is required. The housing containing the pumping cavity is thermally and mechanically isolated from the rail holding the other system components to prevent shock from being transmitted to the other components.

Abstract: An FEL array is comprised of adjacent FEL modules. Each module preferably uses a ribbon beam plasma-anode E-gun (PAG) or another plasma-assisted E-gun to produce a planar E-beam that interacts with a planar wiggler magnetic field. The modules may share a common electron gun. A control signal is input through a phase priming array to preselect the radiation mode. A planar, distributed Bragg resonator/reflector is used to set up a high-Q cavity, enabling the low gain module to produce high power radiation. The FEL modules are arranged in an array to reduce the output radiation flux density while achieving high output power density in the far-field, and to permit beam steering by phase control of individual modules. The relatively low current density of the individual E-guns lessens the size of the guiding magnetic field in each module to the extent that the wiggler magnetic field alone is sufficient to perform this guiding function.

Abstract: A laser device having a support structure of unitary form including having connected first and second portions, the first of which extends outwardly from the connection portion to a free end which is defined by a groove and spaced surfaces on opposite sides thereof. A crystal gain medium is positioned in the groove and diode laser pump sources are located on opposite sides of the groove on the spaced surfaces and are constructed of heat sink members attached to the surfaces and a plurality of laser diodes mounted on selected ones of the heat sinks in positions to optically couple the laser diode outputs to the crystal gain medium rod.

Abstract: An amplifier for use with fiber optic systems comprises a neodymium YAG crystal placed in series with a signal-carrying optical fiber. The ND:YAG crystal is supplied by the optical fiber with both the signal to be amplified, and pumping illumination. The pumping illumination is coupled onto the optical fiber by a multiplexing coupler which is used to combine the signal to be amplified and illumination from a pumping illumination source onto a single optical fiber. The pumping illumination inverts the neodymium ions within the ND:YAG crystal. The signal to be amplified propagates through this crystal to stimulate emission of coherent light from the neodymium ions, resulting in amplification of the signal.

Abstract: Disclosed is a long life cathode for laser generators consisting of a cathode body having an electron emitting surface in which lasing gas molecules are embedded therein.

Abstract: A miniaturized Q-switch is added to the resonant cavity of a compact laser diode pumped solid state laser to produce short high peak power pulses which are input into a single mode optical fiber to form a compact continuum generator. Q-switching the compact laser diode pumped solid state lasers takes advantage of the relatively high gain and short cavity length to provide a desirable combination of pulsewidth and pulse energy. Nd:YAG or Nd:YLF are useful solid state laser materials for Q-switching, or other longer lifetime rare earth ions such as erbium or holmium for greater energy storage. The Q-switch is formed of a material such as TeO.sub.2, SF.sub.10, or LiNbO.sub.3 with an acoustooptic figure of merit substantially greater tha fused silica. The high peak powers of the lasers are sufficient to exceed the threshold for Raman conversion in the fiber which produces a series of red shifted bands ending in a continuum by stimulated Raman scattering.

Abstract: Higher efficiency in cavity dumping and frequency doubling in a laser used to produce modulated output beam pulses is achieved by deflecting light out of the resonant cavity to a third mirror through a frequency doubler using an electro-optic modulator and a polarizing beamsplitter in the resonant cavity, or using just an acousto-optic modulator to deflect light out of the laser cavity in response to a control signal (electric or acoustic). The frequency doubler in front of the third mirror rotates the frequency doubled light so that it will pass out of the laser cavity through the polarizing beamsplitter, while undoubled frequency light is reflected by the polarizing beamsplitter back into the gain medium of the laser. In the case of using a type-II frequency doubler, a dichroic beamsplitter deflects out the frequency doubled light and passes the undoubled frequency light to the polarizing beamsplitter for return to the laser gain medium.

Abstract: An energy generator (10) that converts matter in the form of a gas into an energy source. The generator functions by injecting a gas, such as hydrogen, into a confined chamber (12). The chamber includes an annular permanent magnet (30) and a rotating magnetic assembly (32) that includes a plurality of magnetic fins (36) that form a funnel shape. The combination of the magnets (30), (36) serves to accelerate and centrifugally confine and cause the gas molecules to collide with one another until they acquire sufficient energy to cause lasing.