Abstract: An excimer or molecular fluorine laser system includes a discharge chamber filled with a laser gas mixture at least including a halogen gas and a buffer gas, a plurality of electrodes within the discharge chamber connected to a power supply circuit for energizing the gas mixture, and a resonator for generating a laser beam including a line-narrowing module on one side of the discharge chamber for reducing a bandwidth of the laser beam. The laser beam is output coupled from the resonator on the same side of the discharge chamber as the line-narrowing module and preferably after the beam is line-narrowed at the line-narrowing module. A substantially total intensity of the laser beam impinges upon a line-narrowing optical element of the line-narrowing module and is thereby line-narrowed. The resonator preferably includes at least one aperture for reducing a bandwidth of the laser beam.

Abstract: A laser includes an optical cavity. A diode laser pumping device is located within the optical cavity. An aprotic lasing liquid containing neodymium rare earth ions fills the optical cavity. A circulation system that provides a closed loop for circulating the aprotic lasing liquid into and out of the optical cavity includes a pump and a heat exchanger.

Abstract: A compression-tuned Bragg grating-based laser 800 includes a pair of optical grating elements 802,804 wherein at least one of the grating elements is tunable by a compression device 812,814. The grating elements may include either an optical fiber 10 having at least one Bragg grating 12 impressed therein encased within and fused to at least a portion of a glass capillary tube 20 or a large diameter waveguide grating element 600 having a core and a wide cladding. The tunable grating element(s) 802,804 are axially compressed, which causes a shift in the reflection wavelength of the gratings 807,809 without buckling the element. The shape of the element may be other geometries (e.g., a “dogbone” shape) and/or more than one grating or pair of gratings may be used and more than one fiber 10 or core 612 may be used. A gain element, such as Erbium doped fiber, is optical disposed between the grating elements to provide the lasing cavity.

Abstract: An etalon as a wavelength selection element is configured by an optical element whose transmittance or reflectivity cyclically varies, such that, of two oscillation lines of different wavelengths and light intensities in fluorine laser, when a center wavelength of an oscillation line having a stronger light intensity is situated at one selected wavelength in the element, a center wavelength of an oscillation line having a weaker light intensity is situated between two adjacent selected wavelengths in the element. Accordingly, it is possible to oscillate an ultra narrow band fluorine laser apparatus by one line only, a wavelength width of this line can be narrowed to about 0.2 pm, and the drop in laser output can be reduced. By monitoring the laser output (output characteristics) with the etalon serving as the wavelength selection element, the wavelength selected by the etalon can be adjusted so as to maximize the output of the laser output from the etalon.

Abstract: A mirror system for use in generating a short duration laser pulse is disclosed. The system includes first and second double-chirped mirrors disposed along an optical path within a cavity, where the second double-chirped mirror includes an additional phase-shifting layer as compared to the first double-chirped mirror. The additional phase-shifting layer causes the mirror system during use to produce a laser pulse that is characterized by oscillations in group delay substantially reduced in amplitude in comparison to oscillations in group delay for a pulse produced by the same system without the additional phase-shifting layer.

Abstract: Disclosed are a system, and method, for producing a directly extracted flow of preferred-spin-polarization-direction electrons. The present invention optically pumped electron spin filter system provides a mixture of, typically alkali, atoms and electron polarization direction enhancing buffer gas, to a, preferably, single chamber essentially enclosed space, into which essentially enclosed space is entered a predominately single handedness, preferably laser system produced, beam of photons which optically pumps electrons in atoms to a dark-ground state with a preferred-spin-polarization, that is maintained in the presence of an imposed magnetic field, which magnetic field is oriented essentially co-linear with said beam of predominately single polarized photons.

Abstract: A Q-switched solid state laser is disclosed comprising a pump radiation source, whose pump radiation is focused through focusing elements in the laser crystal, a resonator formed by reflecting surfaces in which at least one laser crystal, an acousto-optic switch for Q-switching, and, if desired, a freqency-doubling crystal (KTP) are arranged. The acousto-optic Q-switch is connected with an electronic unit generating a high-frequency wave which can be modulated. The Q-switch is controlled by the high-frequency wave in such a way that laser pulses with pulse lengths on the order of magnitude of several microseconds (&mgr;s) and with an energy content on the order of magnitude of several millijoules can be generated by controlling the steepness of the edge of the modulation function of the high-frequency wave.

Abstract: A support section is provided on one side of a stem, which is secured such that at least two leads are projected from both sides. A heat sink section is formed on the upper portion of the support section in a wide width extending to the side of the projecting two leads. A laser chip is mounted on the heat sink section. As a consequence, in the event of a laser chip having a large chip size and a large calorific value, the heat sink section is large-sized to improve heat dissipation characteristics, thereby obtaining a semiconductor laser having a small outside diameter and a thin type optical pickup.

Abstract: The method and apparatus operates to calibrate a transmission laser of the dense wavelength division multiplexer (DWDM). In one example, the transmission laser is a widely tunable laser (WTL) to be tuned to one of a set of International Telecommunications Union (ITU) transmission grid lines for transmission through an optic fiber. The WTL is tuned to the ITU grid using an etalon and a gas cell having acetylene, hydrogen cyanide or carbon dioxide. Initially, the absolute transmission wavelengths of the WTL are calibrated by routing an output beam from the WTL through the etalon and through the gas cell while varying tuning parameters of the WTL to thereby generate an etalon spectrum and a gas absorption spectrum both as functions of the tuning parameters. The etalon and gas absorption spectra are compared, along with input reference information specifying gas absorption as a function of absolute wavelength, to determine the absolute transmission wavelength for the WTL as a function of the tuning parameters.

Abstract: According to the invention, a high power diode pumped solid state laser is provided. The laser includes a first and second reflective surfaces which form an optical resonator cavity. A laser medium, particularly a Nd doped laser medium for example: a Nd:YAG, a Nd:YLF, or a Nd:YVO4 crystal is provided within the laser cavity. A fundamental frequency laser beam propagates from the front and back ends of the laser medium. The first reflective surface is highly reflective for fundamental beam. The second reflective surface is at least partially reflective for fundamental beam. The laser medium is end pumped by at least one diode pumping apparatus for example, a laser diode, or diode array, or fiber coupled laser diodes, whose wavelength matches at least one laser medium absorption band. The diode pumping apparatus is located adjacent either the front end or the back end of the laser medium, or both. The optical resonator cavity is configured to provide a laser beam diameter in the laser medium from about 0.

Abstract: A high power diode laser array system utilizes an external cavity to narrow the spectral width of a high power diode laser array to change the output power normally produced by the diode array from a broad spectrum to a very narrow spectrum. The power output of the laser array system is concentrated over a narrow spectral range which falls within the useable range for particular applications such as optical pumping of noble gas samples for magnetic resonance imaging. The output of the array is received by a collimating element, which collimates the light in a direction perpendicular to the direction of the length of the array of emitters and directs the light on a beam path to a diffraction grating which is oriented at an angle to the incident beam.

Abstract: An ArF excimer laser device for performing an oscillating operation with a repetition rate of more than 3 kHz and an oscillating laser pulse width (Tis) of more than 30 ns. The laser operation is carried out in an initial half-period of an electrical discharge oscillating current waveform of a pulse of reversed polarity generated by a high voltage pulse generating device and in at least two subsequent half-periods. The pressure of the laser gas in the laser chamber is 2.5 to 3.5 atm, the fluorine concentration is 0.12% or less, and the argon gas concentration 3% or less. As a result, the laser pulse width (Tis) can be set to more than 30 ns.

Abstract: A molecular fluorine (F2) laser system includes a seed oscillator and power amplifier. The seed oscillator includes a laser tube including multiple electrodes therein which are connected to a discharge circuit. The laser tube is part of an optical resonator for generating a laser beam including a first line of multiple characteristic emission lines around 157 nm. The laser tube is filled with a gas mixture including molecular fluorine and a buffer gas. A low pressure seed radiation generating gas lamp is alternatively used. The gas mixture is at a pressure below that which results in the generation of a laser emission including the first line around 157 nm having a natural linewidth of less than 0.5 pm. The power amplifier amplifies the power of the beam emitted by the seed oscillator to a desired power for applications processing.

Abstract: An efficient F2 laser is provided with improvements in line selection, monitoring capabilities, alignment stabilization, performance at high repetition rates and polarization characteristics. Line selection is preferably provided by a transmission grating or a grism. The grating or grism preferably outcouples the laser beam. The line selection may be fully provided at the front optics module. A monitor grating and an array detector monitor the intensity of the selected (and unselected) lines for line selection control. An energy detector is enclosed in an inert gas purged environment at slight overpressure. A blue or green reference beam is used for F2 laser beam alignment stabilization and/or spectral monitoring of the output laser beam. The blue or green reference beam advantageously is not reflected out with a atomic fluorine red emission of the laser and is easily resolved from the red emission.

Abstract: In order to improve a laser amplification system, comprising a solid-state body having a laser-active medium, a pumping radiation source for generating a pumping radiation field which passes through the solid-state body several times, an optical pumping radiation imaging means which is arranged between the pumping radiation source and the solid-state body and focuses a leg of the pumping radiation field entering the solid-state body onto the solid-state body and at least one optical refocusing means which focuses a leg of the pumping radiation field exiting from the solid-state body onto the solid-state body again in the form of a leg entering the solid-state body and different to the outgoing leg, in such a manner that as high a pumping radiation power density as possible can be generated in the solid-state body with as little resources as possible it is suggested that the optical refocusing means reshape the leg exiting from the solid-state body into an intermediately collimated leg and reshape the intermed

Abstract: A wiggler that, when used in a free electron laser, reduces the harmonicity of the light emitted from the free electron laser. In general, the reduced harmonicity is accomplished by making the magnetic field distribution of the wiggler to be sinusoidal, rather than like a square wave. The sinusoidal magnetic field distribution reduces the number of harmonics that can be used to approximate the magnetic field distribution of the wiggler, and thus reduces the harmonicity of the light produced by passing an electron beam through the wiggler. In a particular embodiment, the wiggler is composed of pieces or segments of permanent magnets that are arranged along an axis such that their magnetic orientations are perpendicular to the axis, and such that the magnetic field distribution along the axis is sinusoidal.

Abstract: External cavity optically-pumped semiconductor lasers (OPS-lasers) including an OPS-structure having a mirror-structure surmounted by a surface-emitting, semiconductor multilayer (periodic) gain-structure are disclosed. The gain-structure in pumped by light from diode-lasers. The OPS-lasers can provide fundamental laser output-power of about two Watts (2.0 w) or greater. Inactivity frequency-converted arrangements of the OPS-lasers can provide harmonic laser output-power of about one-hundred milliwatts (100 raw) or greater, even at wavelengths in the ultraviolet region of the electromagnetic spectrum. These high output powers can be provided even in single axial-mode operation.

Abstract: A real-time wavelength calibration scheme for a swept laser generates an electrical signal from a swept optical output of the swept laser that is cyclical with respect to the wavelength of the swept optical output over a defined range of wavelengths. The point on the electrical signal at any given time provides an accurate phase for the swept optical output at that point. The electrical signal in turn is calibrated by generating calibration references from the swept optical output using known absorption lines within the defined range of interest. The wavelength of the swept laser is calibrated as a function of a reference wavelength from the known absorption lines and the phase at the given point.

Abstract: Continuously tunable and precisely wavelength-switchable fiber lasers combine fiber Bragg gratings and the transmissive filtering properties of high finesse fiber Fabry-Perot filters. This laser arrangement adapts to multiple wavelength ranges based on the selections of fiber Bragg grating and gain medium and their arrangement to create a wavelength-modulatable and simultaneously rapidly wavelength-switchable narrow linewidth all-fiber laser design. This laser arrangement further results in narrow-linewidth outputs with fast switching speeds between the selected wavelengths.

Abstract: In a dye laser system, a porous bed filter is loaded with dye prior to operation of the system. With repeated firings, the dye solution is filtered by the porous bed filter to remove by-products of the laser process. Solute concentration is monitored and dye and additives removed by the filter are replenished by a metering pump. Precise temperature control assures consistent filtering of dye by the filter for more consistent color and energy output. To control the metering pump, the differential output of a two-channel absorption detector is digitized. The digitized signal is loaded into a counter which drives the metering pump. The useful lifetime of the dye solution is enhanced by incorporating pH buffers in the solution.