Abstract: In an excimer laser apparatus comprising a laser chamber 1 filled with a laser gas, a discharge excitation portion 2 provided in the laser chamber 1, a rotary shaft 3 to which a gas circulating fan 4 for circulating the laser gas is fixed, a shield partition wall 61 for forming a sealed space to enclose the rotary shaft 3, a magnetic bearing of a control type including a rotor portion 32 provided on the rotary shaft 3 side and a stator portion 6 provided outside the shield partition wall 61 and serving to pivotally support the rotary shaft 3 in non-contact, a driving motor 13 provided outside the laser chamber 1, magnetic coupling portions 33, 11 and 121 for transmitting driving force of the driving motor 13 to the rotary shaft 3 through the shield partition wall 61 in non-contact, and rotary shaft sensors 8 and 9 for detecting a position of the rotor portion 32 with respect to the stator portion 6.

Abstract: A toroidal magnet structure for polarizing a magnetic wiggler and a synchrotron normal is provided. This structure comprises a toroid composed of a plurality of magic ring semicircular segments, with an equatorial slot extending about a periphery of the toroid. The toroid further comprises a central hollow core and a toroidal axis perpendicular to the toroid. The magic ring semicircular segments are wedge-shaped to prevent magnetic flux leakage between segments and to form a continuous toroid. The equatorial slot allows emission of radiation outside the toroid. An electron beam means injects an electron beam into the central hollow core. The magnetic field thus created has a vertical component Bv within the central hollow core and a periodic horizontal component Bh, alternating in direction from ring to ring. The vertical component Bv keeps the electron beam in a generally circular electron path around the toroid and is constant along the entire path.

Abstract: A gas discharge laser capable of operating at pulse rates in the range of 4,000 Hz to 6,000 Hz at pulse energies in the range of 5 mJ to 10 mJ or greater.

Abstract: An excimer laser apparatus comprises a container sealing a laser gas including a halogen gas therein, a pair of discharge electrodes disposed in the container for inducing an electric discharge capable of oscillating a laser light, and a circulating fan with a shaft for producing a high-speed laser gas stream between a pair of the discharge electrodes. Both ends of the shaft are rotatably supported by rotor-stator mechanisms, or one end of the shaft is rotatably supported by a rotor-stator mechanism, and the other end of the shaft is supported by a magnetic bearing. The rotor-stator mechanism comprises a rotor attached to the shaft of the circulating fan, a stator provided at a position opposed to the rotor, an electric motor winding provided in the stator for applying torque to the rotor, and a position control winding provided in the stator for producing a magnetic force to levitate and support the rotor.

Abstract: An emission timing control apparatus for a pulsed laser including a magnetic pulse compression circuit having a switching section for carrying out a switching operation to connect and disconnect a charging power source to and from the magnetic pulse compression circuit. The pulsed laser executes pulsed laser oscillation at a prescribed repetition frequency by turning on the switching section with a pulse oscillation synchronizing signal having the prescribed repetition frequency received from a semiconductor exposure apparatus, in which the emission timing control apparatus includes a reference delay time setting section for setting a prescribed reference delay time, and delay section for delaying a pulse oscillation synchronizing signal received from the semiconductor exposure apparatus by the time difference &tgr; calculated in the delay time calculating section and outputting to the switching section.

Abstract: Disclosed is a novel hybrid wiggler as a kind of insertion devices, for example, in an electron accelerator. Different from a conventional hybrid wiggler consisting of two oppositely facing arrays each formed of an alternate arrangement of a plurality of permanent magnet blocks and a plurality of pole pieces of a soft magnetic material to generate a sine-curved periodical magnetic field in the gap space between the arrays to cause meandering of electron beams, each of the pole pieces is sandwiched on the lateral surfaces with a pair of auxiliary permanent magnet blocks so that the periodical magnetic field generated in the gap space can be greatly strengthened.

Abstract: A wavelength selective laser system and associated method are provided that produce laser beams having wavelengths that are only slightly different, but that permit a composite return signal to be selectively processed in accordance with the wavelengths of the signals that comprise the composite return signal. The wavelength selective laser system includes first and second lasers for producing respective laser beams. Each of the first and second lasers define a nominal gain spectrum. However, the wavelength selective laser system also includes a magnetic field generator disposed about the second laser for altering the gain spectrum of the second laser such that the wavelengths of the laser beams produced by the first and second lasers differ by at least one part per million. As such, the first laser will emit signals having a first wavelength and the second laser will emit signals having a second wavelength.

Abstract: This invention relates to an excimer laser oscillation apparatus which has a laser chamber which stores a laser gas containing a gas mixture of at least one inert gas selected from the group consisting of Kr, Ar, and Ne, and F2 gas, and in which an inner surface thereof has a reflection-free surface with respect to light of a desired wavelength of 248 nm, 193 nm, or 157 nm, and the uppermost surface of the inner surface consists of a fluoride, an optical resonator which is made up of a pair of reflection mirrors arranged to sandwich the laser chamber therebetween, and in which the reflectance of the reflection mirror on the output side is 90% or more and microwave introduction means, arranged on the laser chamber, for continuously exciting the laser gas in the laser chamber.

Abstract: The present invention provides a reliable modular production quality excimer laser capable of producing 10 mJ laser pulses in the range of 1000 Hz to 2000 Hz with a full width half, maximum bandwidth of about 0.6 pm or less. Replaceable modules include a laser chamber, a pulse power system comprised of three modules; an optical resonator comprised of a line narrowing module and an output coupler module; a wavemeter module, an electrical control module, a cooling water module and a gas control module. Important improvements have been provided in the pulse power unit to produce faster rise time and improved pulse energy control.

Abstract: A device for loading of a light wave guide formed as a fiber with exciting energy in form of a pump light supply for producing a laser light has a fiber, such as a laser fiber and an amplifier fiber, which is wound with at least one winding in a coil-like manner for a transverse coupling of exciting pump light.

Abstract: A method and surgical technique for corneal reshaping and for presbyopia correction are provided. The preferred embodiments of the system consists of a scanner, a beam spot controller and coupling fibers and the basic laser having a wavelength of (190-310) nm, (0.5-3.2) microns and (5.6-6.2) microns and a pulse duration of about (10-150) nanoseconds, (10-500) microseconds and true continuous wave. New mid-infrared gas lasers are provided for the corneal reshaping procedures. Presbyopia is treated by a method which uses ablative laser to ablate the sclera tissue and increase the accommodation of the ciliary body. The tissue bleeding is prevented by a dual-beam system having ablative and coagulation lasers. The preferred embodiments include short pulse ablative lasers (pulse duration less than 200 microseconds) with wavelength range of (0.15-3.2) microns and the long pulse (longer than 200 microseconds) coagulative lasers at (0.5-10.6) microns.

Abstract: Laser diode pumped mid-IR wavelength sources include at least one high power, near-IR wavelength, injection and/or sources wherein one or both of such sources may be tunable providing a pump wave output beam to a quasi-phase matched (QPM) nonlinear frequency mixing (NFM) device. The NFM device may be a difference frequency mixing (DFM) device or an optical parametric oscillation (OPO) device. Wavelength tuning of at least one of the sources advantageously provides the ability for optimizing pump or injection wavelengths to match the QPM properties of the NFM device enabling a broad range of mid-IR wavelength selectivity. Also, pump powers are gain enhanced by the addition of a rare earth amplifier or oscillator, or a Raman/Brillouin amplifier or oscillator between the high power source and the NFM device. Further, polarization conversion using Raman or Brillouin wavelength shifting is provided to optimize frequency conversion efficiency in the NFM device.

Abstract: An isolation means used in conjunction with supplying energy to a laser, which isolates a power supply from the pulser circuit, and commutates a switch which activates the discharge of energy to the laser.

Abstract: In a laser such as a mode-locked or Q-switched laser, one of the resonator reflectors comprises a switchable Faraday rotator mirror coupled to a switchable magnetic field source. The operation of the laser is therefore controlled by the application of the magnetic field to the Faraday rotator device. When no magnetic field is applied, the device behaves as an isolator and thereby breaks the signal path between the resonator reflectors. When a saturation magnetic field is applied, the reflectors, disposed on opposite sides of the optical gain medium, thereby form a cavity such that lasing will occur. The device may be formed of discrete components or fabricated as an integrated optical device.

Abstract: An extremely compact soft x-ray and/or extreme ultraviolet laser is disclosed that can be repetitively fired within short time intervals. The laser generates a plasma within a capillary (3) by flowing through the capillary (3) a fast high current pulse generated by a very compact liquid dielectric (1) transmission line (9) geometry.

Abstract: The invention provides a device with an improved tunable laser structure, the structure useful with surface emitting lasers and capable of exhibiting desirable latchability. The tunable laser of the invention contains a laser structure having a lower reflector, an active laser region, and an upper reflector. The upper reflector contains a non-moveable reflector portion located adjacent the active laser region and a moveable reflector portion located a spaced distance from the non-moveable reflector portion. A magnetic material is located either on a surface of the moveable reflector portion or on a surface in contact with the moveable reflector portion, and a programmable magnet is located near the magnetic material, the magnet capable of inducing controlled movement of the magnetic material. This movement in turn induces movement of the moveable reflector portion such that the spaced distance between the moveable reflector portion and the non-moveable reflector portion is capable of being adjusted.

Abstract: A system is disclosed for developing a conditioned electron beam of high quality for an exemplary application to a free-electron source of coherent radiation. The system comprises: a source for producing an electron beam of relatively high energy, a microwave source for generating a microwave field, and a wiggler for generating transverse to the electron beam a periodic magnetic field which cooperates with the microwave field to interact with the electron beam and develop a conditioned electron beam of high quality.

Abstract: The present invention provides a reliable modular production quality excimer laser capable of producing 10 mJ laser pulses at 2000 Hz with a full width half, maximum bandwidth of about 0.6 pm or less. Replaceable modules include a laser chamber; a pulse power system comprised of three modules; an optical resonator comprised of a line narrowing module and an output coupler module; a wavemeter module, an electrical control module, a cooling water module and a gas control module. Improvements in the laser chamber permitting the higher pulse rates and improved bandwidth performance include a single upstream preionizer tube and a high efficiency chamber. The chamber is designed for operation at lower fluorine concentration. Important improvements have been provided in the pulse power unit to produce faster rise time and improved pulse energy control.

Abstract: The present invention provides an electric discharge gas laser having a laser cavity in which is contained a laser gas and a fan for circulating the laser gas. The fan is supported by an active radial magnetic bearing system and driven by a brushless DC motor in which the rotor of the motor and the rotors of at least two radial bearings are sealed within the gas environment of the laser cavity and the motor stator and the coils of the bearing magnets are located outside the gas environment. No thrust bearing is provided. Axial positioning of the shaft is provided by reluctance centering produced by the at least two radial magnetic bearings and the brushless DC motor. In a preferred embodiment the motor stator is larger in the axial direction than the rotor to increase the magnetic centering effect.

Abstract: An electric discharge gas laser having a laser cavity in which is contained a laser gas and a fan for circulating the laser gas. The fan is supported in position radially by a roller bearing system and axially at least in part by magnetic forces. In a preferred embodiment the magnetic forces are supplied by a brushless DC motor in which the rotor of the motor is sealed within the gas environment of the laser cavity and the motor stator is located outside the gas environment. The magnetic center of the rotor is offset from the center of the stator to produce a magnetic reluctance generated force on the shaft that acts axially on the shaft toward the non-drive end and is reacted by a ball and plate bearing assembly mounted along the axis of rotation at the opposite end of the shaft.

Abstract: An isolation means used in conjunction with supplying energy to a laser, which isolates a power supply from the pulser circuit, and commutates a switch which activates the discharge of energy to the laser.

Abstract: The present invention provides a reliable modular production quality excimer laser capable of producing 10 mJ laser pulses in the range of 1000 Hz to 2000 Hz or greater. Replaceable modules include a laser chamber; a pulse power system comprised of three modules; an optical resonator comprised of a line narrowing module and an output coupler module; a wavemeter module, an electrical control module, a cooling water module and a gas control module. Important improvements have been provided in the pulse power unit to produce faster rise time and improved pulse energy control. These improvements include an increased capacity high voltage power supply with a voltage bleed-down circuit for precise voltage trimming, an improved commutation module that generates a high voltage pulse from the capacitors charged by the high voltage power supply and amplifies the pulse voltage 23 times with a very fast voltage transformer having a secondary winding consisting of a single four-segment stainless steel rod.

Abstract: A resonant optical device has a rod-like resonator made of a fiber-reinforced resin for resonant vibration. A reflecting mirror is supported on the leading edge of the resonator. A drive unit oscillates the resonator in a circumferential direction. The base edge of the resonator is anchored to a stationary platform. The reflecting mirror is oscillated by a torsional oscillation produced by oscillation from the drive unit so as to scan light incident on the reflecting mirror. The resonator satisfies the expression G/.rho..gtoreq.12.times.10.sup.6 Pa.multidot.kg.sup.-1 .multidot.m.sup.3, where the horizontal elastic modulus of the resonator is designated G, and the density is designated .rho.. The resonator also satisfies the expression .tau./G.gtoreq.0.01, where the torsional stress tolerance is designated .tau.. In one embodiment, the fiber-reinforced resin is a carbon fiber-reinforced resin.

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.

Abstract: A method for doping semiconductors used for far infrared lasers with non-hydrogenic acceptors having binding energies larger than the energy of the laser photons. Doping of germanium or silicon crystals with beryllium, zinc or copper. A far infrared laser comprising germanium crystals doped with double or triple acceptor dopants permitting the doped laser to be tuned continuously from 1 to 4 terahertz and to operate in continuous mode. A method for operating semiconductor hole population inversion lasers with a closed cycle refrigerator.

Abstract: A robust method of stabilizing a diode laser frequency to an atomic transition is provided. The method employs Zeeman shift to generate an anti-symmetric signal about a Doppler-broadened atomic resonance, and, therefore, offers a large recapture range as well as high stability. The frequency of a 780 nm diode laser, stabilized to such a signal in Rb, drifts less than 0.5 MHz.sub.pk-pk (one part in 10.sup.9) in thirty-eight hours. This tunable frequency lock may be inexpensively constructed, requires little laser power, rarely loses lock, and may be extended to other wavelengths by using different atomic species.

Abstract: In accordance with the invention, a tunable laser uses magnets to apply mechanical strain on fiber Bragg grating reflectors or laser cavities in order to induce a change in lasing wavelength. The strain can be tensile or compressive. The tunable laser comprises a laser cavity including a laser material for emitting light in response to stimulating light and two end reflectors one or more of which can be a Bragg grating. In preferred embodiments, latchable programmable magnets vary the grating periodicity and/or cavity length in a controlled, accurate manner so as to achieve desired tuning of the laser over a broad range of wavelengths. The latchable magnets hold the wavelength in the shifted position without the need for sustained power.

Abstract: The present invention is a laser (12) having a resonator (28) between an output coupling mirror (20) and a high-reflection mirror (26). A photoelastic plate (38) is incorporated in a photoelastic cell (24), or a photoelastic mirror (36) used in place of the high-reflection mirror (26). The photoelastic plate (38) is placed in the resonator (28) and introduces an artificial anisotropy to the laser (12). The photoelastic plate (38) has privileged directions (34), which are aligned with the axes of the artificial anisotropy. A magnetic field (32) is applied transversely to the resonator (28), in alignment with one of the privileged directions (34), to produce two orthogonal linearly polarized frequencies in an output beam (30) with the Zeeman effect.

Abstract: An excimer laser system having a laser chamber containing elongated electrodes and an excimer laser gas and a high voltage pulse power supply having fine digital regulation for supplying high voltage electrical pulses to the electrodes. The high voltage pulse power supply includes a power supply and a magnetic switch circuit for compressing and amplifying the output of the power supply. The power supply includes a silicon controlled rectifier which provides a direct current output to an inverter which converts the output of the silicon controlled rectifier to high frequency alternating current which is in turn amplified by a step up transformer. An output stage diode rectifier in combination with an inductor converts this high frequency high voltage current back to direct current. A control board comprising electronic circuits controls the power supply to provide high voltage pulses at a frequency of at least 1000 Hz.

Abstract: A free electron laser amplifier provides a scalloping annular electron beam that interacts with the axial electric field of a TM.sub.0n mode. A waveguide defines an axial centerline and, a solenoid arranged about the waveguide produces an axial constant magnetic field within the waveguide. An electron beam source outputs a annular electron beam that interacts with the axial magnetic field to have an equilibrium radius and a ripple radius component having a variable radius with a ripple period along the axial centerline. An rf source outputs an axial electric field that propagates within the waveguide coaxial with the electron beam and has a radial mode that interacts at the electron beam at the equilibrium radius component of the electron beam.

Abstract: A self-seeded free electron laser (FEL) provides a high gain and extraction efficiency for the emitted light. An accelerator outputs a beam of electron pulses to a permanent magnet wiggler having an input end for receiving the electron pulses and an output end for outputting light and the electron pulses. An optical feedback loop collects low power light in a small signal gain regime at the output end of said wiggler and returns the low power light to the input end of the wiggler while outputting high power light in a high signal gain regime.

Abstract: A split reciprocal polarization switch (SRPS) for use in constructing high performance switching devices used in fiber optics. The SRPS allows selective changes in the polarization of one or the other of two optical rays passing therethrough along first and second bi-directional ray paths of the SRPS so that they emerge therefrom with the same polarizations. The SRPS includes a switching section for selectively changing the optical polarization of optical rays according to a selected state of the switching section, and a split section including a first and second sections having different polarization changing characteristics.

Abstract: An ion laser apparatus having an electromagnet for converging plasma is disclosed for providing stabilized laser operation for a long time. An electromagnet control circuit provided within a power source is capable of changing either voltage or current of the electromagnet while an ion laser tube is discharged. Due to the change of magnetic field of the electromagnet during discharging of the ion laser tube, the plasma configuration is changed while adding intensity to the convergence of the plasma within the ion laser tube, thus inhibiting a stay of a gas within a fine tube to provide stabilized laser operation.

Abstract: A high-efficiency plasma confining method, and a laser oscillating method of oscillating a laser, confine a plasma generated by entering a laser beam via an entry of a superconducting cylinder within the cylinder. The methods include the step of inhibiting diffusion or expansion in the radial or axial direction of the generated plasma by reducing the inside diameter of the cylinder between the entrance and an exit thereof. A magnetic line of force may be generated in the axial direction by winding a coil around the superconducting cylinder, to thereby confine the plasma. A laser oscillator for carrying out the method includes a superconducting cylinder, a supply mechanism for supplying a gas or a solid into the cylinder, and a laser irradiating mechanism. The inside diameter of the cylinder is reduced between an entry and an exit thereof, or the inside diameter of the cylinder is reduced at the entry and the exit thereof.

Abstract: The invention relates to a laser cavity having an active laser medium and two mirrors forming a Fabry-Perot cavity, characterized in that the cavity is at the optical stability limit and in that there are means for varying the optical length of the cavity, so as to pass from an optically unstable state into a stable state.

Abstract: A microlaser cavity to a microlaser incorporating an active solid medium (38) and means (44) for switching the cavity, whilst also having, within said cavity, at least one element (46) of an optically nonlinear material, making it possible to multiply the basic frequency of the laser cavity by a factor n (n.gtoreq.2).

Abstract: Described are a method for generating a laser beam and a laser device for practising the method. In a first step gas is ionised by means of X-rays. In a second step the electron density is increased by means of a pre-discharge. In a third step the main discharge takes place. Between the second and third steps, an electron redistribution occurs. According to the invention, the electron redistribution rate and/or the time delay between the pre-discharge and the main discharge are adjustable and controllable in relation to each other, for achieving a particular desired beam profile, such as a uniform profile. Because that delay is preferably set by varying one or more process parameters, an improtant advantage is achieved in that it is possible with one and the same laser device to modify the beam profile in a simple and flexible manner even during the operation of the laser device.

Abstract: An apparatus for producing high intensity laser radiation. A vacuum enclosure is provided which includes first and second magnets at each end, and a magnetic field applied along the length of the enclosure. The magnets and applied magnetic field forms a magnetic mirror for electrons of a near relativistic energies introduced into the vacuum enclosure. A thin dielectric material is provides which is charged on each side by some of the electrons which strike the surfaces of the dielectric. The charged dielectric provides high intensity electrostatic fields at the edges thereof. The strength of the magnets and applied magnetic field are selected to produce an oscillation of electrons which pass through the high intensity electrostatic fields and are subject to a radial acceleration which produces free electron lasing. The laser energy is collected by an optical cavity within the enclosure. The laser energy exits an optical port within the enclosure.

Abstract: A p-Ge laser operating at submillimeter wavelengths in Voigt configuration using a regular permanent magnet. The invention is improvement over prior art Ge Lasers which use superconducting magnets that require liquid helium to cool the magnets along with the Ge crystal. Although the subject invention requires cooling(refrigerant) of the Ge crystal itself, it does not need liquid helium. The permanent magnet can be Nd.sub.2 Fe.sub.14 B. The emissions using the novel invention were observed over a wider range of electric-field magnitude in Voigt configuration at a given magnetic field as compared to that of the prior system. The free space beam profile of the subject invention is Gaussian. The emission-strength of the subject invention is sufficient between 4 and 10K that a closed-cycle refrigerator can be used to cool the crystal rather than the liquid helium used in all prior p-Ge lasers.

Abstract: The invention provides a laser oscillator including (a) laser medium having a characteristic that distortion is caused in the laser medium by applying electric field thereto, (b) an optical pumping source for exciting the laser medium to thereby generate laser beam, (c) a pair of terminals through which a voltage is applied to the laser medium, and (d) an optical resonator including a total reflection coating attached to one of end surfaces of the laser medium and a partial reflection coating attached to the other of end surfaces of the laser medium. The laser oscillator provides advantages as follows: (a) laser outputs can be stabilized; (b) a laser oscillator can be small-sized; and (c) a laser apparatus can be also small-sized by incorporating the small-sized laser oscillator thereinto.

Abstract: An optical isolator comprises an input polarizer configured to pass light at a predetermined optical polarization axis to a Faraday rotator and thereafter through an output polarizer. A magnet is disposed remotely and laterally away from the Faraday rotator, such that the external field of the magnet maintains the magnetization of the Faraday rotator substantially saturated. In accordance with another aspect of the invention the output polarizer is rotatably adjustable to substantially fine tune the isolator to a given laser wavelength. To this end light is transmitted through an input polarizer, and through a Faraday rotator magnetized in a first magnetization direction so as to rotate the polarization axis of the light passing through the Faraday rotator. The output polarizer is rotatably adjusted until such time that substantially no light travels through the output polarizer.

Abstract: A spherical magnet structure having an axis about which an equatorial gap disposed into the periphery thereof, is constructed to sustain a magnetic field across the gap with the field magnitude varying periodically over a circular pattern in a plane passing perpendicularly through the axis. Such construction includes magnet segments which are configured and aligned across the gap in wedge-shaped arrangements to sustain magnetic field contributions thereacross. A source of wiggler radiation is derived by combining the magnet structure with means for introducing charged particles into the gap thereof, wherein the field influences the particles to travel circularly in a continuous periodic path.

Abstract: An ion laser apparatus capable of simultaneous oscillation at a plurality of wavelengths is provided, which makes it possible to stabilize not only the overall output beam but also each component of the output beam. A laser tube having a pair of optical mirrors at each end is driven by a first electric current, thereby causing a specific electric discharge in the tube. A magnetic-field generator is driven by a second electric current, thereby generating a specific magnetic field in the tube to focus or collect a plasma generated in the tube. An optical beam splitter splits a reference beam generated from the output laser beam into first and second feedback beams. First and second detectors detect the feedback beams to thereby generate first and second electric signals, respectively. The electric discharge in the tube is controlled by the use of the first electric signal, and the magnetic field in the tube is controlled by the use of the second electric signal.

Abstract: An excitation system for a gas laser featuring a multiplicity of gain channels uses a resonant cavity to provide broad band RF power division and impedance matching to the multiplicity of gain channels. Integral anode and grid resonant tank circuits featuring positive feedback may be employed to provide a self-excited power oscillator having a very high power capability with good efficiency at low cost. A smaller and higher frequency multi-channel excitation system fabricated from stripline resonator elements may be used for driving small scale multi-channel lasers. A common optical extraction system features either a stable, an unstable, or a hybrid optical cavity mode, with phase-locked or non-phase locked output performance, achieved via external or self-injection.

Abstract: A discharge tubule has improved first and second side portions made of a material having a higher resisitvity to the sputtering, for example, any of titanium carbide (TiC), beryllia (BeO) and boron carbide (B.sub.4 C), wherein the first and second side portions are exposed to a strong sputtering by a plasma gas generated by a large current discharge. The selected material of any of the titanium carbide (TiC), beryllia (BeO) and boron carbide (B.sub.4 C) makes the discharge tubule free from receiving any damage due to the strong sputtering by the plasma gas generated by the large current discharge and further free from any deformation thereof. This ensures that the ion laser tube has a long life time.

Abstract: Electron orbits from a helical axial wiggler in an axial guide field are absolutely unstable as power is extracted from the particles. For off-axis beams an axial FEL mechanism exists when the axial electric field in a TM mode is wiggled to interact with the axial velocity of the electrons that form the beam. The interaction strength is comparable to that for helical FELs and is insensitive to beam orbit errors. The orbits for this mechanism are extremely stable in the absence of space charge and lead to high extraction efficiencies without particle phasing incoherence or interception. This interaction mechanism is suitable for use with intense annular electron beams for high power generation at microwave frequencies.

Abstract: In a magnetooptical element comprising a single crystal of Cd.sub.1-x-y Mn.sub.x Hg.sub.y Te, the single crystal has a composition in an area defined in a quasi three-element phase diagram of MnTe--HgTe--CdTe by four points of:Mn.sub.0.01 Hg.sub.0.04 Cd.sub.0.95 Te, Mn.sub.0.01 Hg.sub.0.1 Cd.sub.0.89 Te, Mn.sub.0.12 Hg.sub.0.17 Cd.sub.0.71 Te, and Mn.sub.0.25 Hg.sub.0.04 Cd.sub.0.71 Te.This renders the magnetooptical element suitable for use in a wavelength range between 0.8 micrometer and 1.1 micrometers.

Abstract: The present invention is a laser with a high reflector mirror and an output coupler mirror defining a laser resonator having an optical axis and optical path length. A gain medium, with a first refractive index and a first Verdet constant, is positioned in the resonator. The laser also includes an apparatus to excite and cause a population inversion in the gain medium to produce an output laser beam. An optically transparent medium is positioned in the laser resonator. The optically transparent medium has a second refractive index and a second Verdet constant. The second Verdet constant is typically larger than the first Verdet constant. One or more permanent and electromagnets are positioned at least partially around the exterior of the laser resonator.

Abstract: The present invention provides a reliable modular production quality excimer laser capable of producing 10 mJ laser pulses in the range of 1000 Hz to 2000 Hz or greater. Replaceable modules include a laser chamber; a pulse power system comprised of three modules; an optical resonator comprised of a line narrowing module and an output coupler module; a wavemeter module, an electrical control module, a cooling water module and a gas control module. Important improvements have been provided in the pulse power unit to produce faster rise time and improved pulse energy control. These improvements include an increased capacity high voltage power supply with a voltage bleed-down circuit for precise voltage trimming, an improved communication module that generates a high voltage pulse from the capacitors charged by the high voltage power supply and amplifies the pulse voltage 23 times with a very fast voltage transformer having a secondary winding consisting of a single four-segment stainless steel rod.

Abstract: A permanent magnet design including a Chiron Wiggler, which is able to produce a magnetic field to accelerate and focus electrons in a high frequency laser without the use of an externally powered, current driven solenoid.