Abstract: A fiber-optic laser source capable of emitting multiple useful wavelengths at the same time, including multiple ITU grid wavelengths, is disclosed. The laser preferably comprises a diode-pumped rare-earth doped fiber amplifier as gain medium, a periodic filter to define a first set of possible lasing wavelengths corresponding to ITU grid lasing wavelengths, and a resonant filter for defining a subset of the first set of wavelengths. The arrangement is enclosed in a ring resonator. The ring resonator may be made, in part or in total, with polarization-maintaining optical fiber. The resonator may also comprise in-line optical isolators to ensure unidirectional operation and to eliminate undesired reflections. A gain-flattening filter may also be included within the resonator depending on the desired output characteristics of the laser. The laser may be designed to operate in a set of single cavity longitudinal modes.

Abstract: A femtosecond laser-electron X-ray source. A high-brightness relativistic electron injector produces an electron beam pulse train. A system accelerates the electron beam pulse train. The femtosecond laser-electron X-ray source includes a high intra-cavity power, mode-locked laser and an x-ray optics system.

Abstract: A wavelength monitor capable of obtaining an optical detection signal of high quality is proposed. In the wavelength monitor, a light incident surface of an optical filter is disposed with an inclination relative to the light incident direction. With this arrangement, it is possible to make the route of a reflection light that has been reflected from the light incident surface of the optical filter deviate large from the route of an incident light that has been incident to the optical filter. Consequently, the reflected light is prevented from being incident to a semiconductor laser device or optical detectors.

Abstract: The present invention provides an optical filter module. In one embodiment, the wavelength locker module includes an optical interferometer or filter, such as an etalon. In addition, the wavelength locker module also includes an electrically nonconductive material having a high thermal conductivity substantially surrounding the etalon.

Abstract: A tunable external cavity laser apparatus and method of laser operation. The apparatus includes a gain medium having first and second facets defining a facet laser cavity in which a first portion of light is internally reflected to produce a first lasing condition having a first reflection phase. A reflective element is positioned opposite the second facet of the gain medium, forming an external laser cavity defined by the first facet and reflective element. A second portion of light is internally reflected within the external cavity to produce a second lasing condition having a second reflection phase. A phase adjustment means is employed to adjust the first reflection phase relative to the second reflection phase so as to control a characteristic of the output beam emitted from the apparatus, such as the power output level of the beam. In one aspect, the relative phase is adjusted by controlling the temperature of the gain medium.

Abstract: An excimer or molecular fluorine laser system is provided which emits a laser beam during operation and has a gas mixture with a gas composition initially provided within a discharge chamber. The laser system includes a discharge chamber containing a laser gas mixture at least including a halogen-containing species and a buffer gas, multiple electrodes within the discharge chamber and connected to a discharge circuit for energizing the gas mixture, a resonator for generating a laser beam, an electrostatic precipitator for having a voltage applied thereto and for receiving and precipitating contaminant particulates from a flow of the gas mixture, and a processor for monitoring the corona discharge ignition voltage of the electrostatic precipitator and for determining a status of said gas mixture based on the monitored voltage.

Abstract: A method and a system for filtering a user light beam using a periodic filter having a frequency response stabilized at an absolutely calibrated value are provided. A primary light beam is generated by a tunable laser source and portions thereof are filtered by an absolute reference filter and the periodic filter. First the frequency of the laser source is automatically locked on the absolute reference filter, and then the frequency response of the periodic filter is locked relative to the frequency of the laser source. The frequency response of the periodic filter is therefore continuously maintained at the proper calibration. User input and output are provided to pass the user light beam through the stabilized periodic filter independently of the filter stabilization process. A broadband absolutely calibrated optical source and a method for absolutely calibrating an optical spectrum analysis device are also provided.

Abstract: An excimer or molecular fluorine laser, such as a KrF- or ArF-laser, or a molecular fluorine (F2) laser, particularly for photolithography applications, has a gas mixture including a trace amount of a gas additive. The concentration of the gas additive in the gas mixture is optimized for improving energy stability and/or the overshoot control of the laser output beam. The concentration is further determined and adjusted at new fills and/or during laser operation based on its effect on the output pulse energy in view of constraints and/or aging on the discharge circuit and/or other components of the laser system. Attenuation control is also provided for increasing the lifetimes of components of the laser system by controlling the concentration of the gas additive over time. A specific preferred concentration of xenon is more than 100 ppm for improving the energy stability and/or overshoot control.

Abstract: The present invention relates to an excimer laser comprising a charging circuit including a parallel connection of a storage capacitor (CB) with a series connection of a reoscillation inductance (LB), a charging inductance (LL) and a firing device (Z) for firing the excimer laser, wherein the storage capacitor (CB) has at least a terminal for connecting a power supply (UL), a peaking capacitor (CP) connected in parallel with the charging inductance (LL), a discharge path including two opposed electrodes (E1, E2), connected in parallel with the peaking capacitor (CP), and a driving device for driving the firing device (Z), wherein the firing device (Z) is formed as a MOSFET array. The invention also relates to a corresponding method of operating such an excimer laser.

Abstract: Current control biasing of a ring laser gyroscope is employed to protect electrode seals. A frame of a ring laser gyroscope has more than one electrode attached to it. An electric field is created between the electrodes during the operation of the gyroscope, which causes ions in the frame to migrate towards a lowest electrical potential. Electrode seals are located between the electrodes and the frame. By providing a positive power supply voltage and connecting the current control to the non-ground side of the power supply, the mounting structure may be at the lowest electrical potential. The ions will then migrate towards the mounting structure, which significantly reduces migration to the electrodes.

Abstract: A method for producing molecular Iodine for introduction into the laser cavity of a Chemical-Oxygen-Iodine-Laser (COIL) includes the step of preparing a solid mixture that contains a primary component and an additive component. The solid mixture is formulated to generate a gas having a high concentration of molecular Iodine when ignited. The primary component of the mixture is composed of oxidizer and fuel at a substantially stoichiometric ratio and includes at least one Iodine compound. The additive component is provided to cool the relatively high temperature gas that is created during combustion of the primary component. The result is a gas at a relatively low temperature in which most of the Iodine is present as molecular Iodine. The additive component is preferably an Iodine compound that either absorbs heat during decomposition such as Iodine Pentoxide (I2O5) or an Iodine compound that absorbs heat during sublimation such as solid Iodine.

Abstract: An optical wavelength conversion device includes: two or more non-linear optical crystals each having approximately identical phase matching conditions for a fundamental wave light and a second harmonic wave light; and a phase adjusting section inserted between the adjacent non-linear optical crystals, wherein the phase adjusting section a dispersion characteristic which is different from that of the non-linear optical crystals, and the phase adjusting section is formed so as to allow at least one of a refractive index or a length thereof to be modulated.

Abstract: Room temperature lasing from optically pumped single defect in a two-dimensional photonic bandgap crystal is illustrated. The high Q optical microcavities are formed by etching an array of air holes into a half wavelength thick multiquantum well waveguide. Defects in the two-dimensional photonic crystal or used to support highly localized optical modes with volumes ranging from 2 to 3 (&lgr;/2n)3. Lithographic tuning of the air hole radius and the lattice spacing is used to match the cavity wavelength to the quantum well gain peak, as well as to increase cavity Q. The defect lasers were pumped with 10-30 nsec pulse of 0.4-1 percent duty cycle. The threshold pump power was 1500 milliwatts. The confinement of the defect mode energy to a tiny volume and the enhancement of the spontaneous emission rate make the defect cavity an interesting device for low threshold, high spontaneous emission coupling factor lasers, and high modulation rate light emitting diodes.

Abstract: A rapidly oscillating laser light source is produced that exhibits extended pulse duration having a substantially uniform amplified output. A pulsed beam of laser light having a given wavelength, frequency, duration and intensity is produced such that the pulse shape is controlled. The pulsed beam is amplified using a fiber amplifier which exhibits inherent changes in amplifier gain at the frequencies of interest. The fiber amplifier is continuously pumped. A feedback signal is provided with the amplified pulse characteristics and is used to adjust the pulse shape of the pulsed beam of laser light before amplifying, such that the intensity is changed over the pulse duration to generate a substantially uniform amplified output during each pulse.

Abstract: The present invention provides for the coupling of laser diodes into electromagnetic radiation transmitting fibers wherein coupling efficiency is improved by improving the spatial brightness of multi-mode diode lasers as they are coupled into double-clad fibers. A Bragg grating 100 is fabricated into the core 102 of a double-clad fiber 104 coupled to a multi-mode diode laser 106. The output 108 from the multi-mode diode laser 106 is coupled into the core 102 and inner cladding 110 of the double-clad fiber by proximity or by one or more focusing objectives 112. The Bragg grating 100 in the core 102 of the double-clad fiber 104 is written at the wavelength of the multi-mode diode laser 106. The original output 108 from the multi-mode diode laser 106 strikes the Bragg grating 100 which reflects feedback 114 back to the diode laser 106.

Abstract: A method of generating light pulses in an ultrawide band ranging from the near-infrared region to the near-ultraviolet region. Fundamental sub-picosecond pulses emitted from an ultrashort pulse laser (1) are passed through a nonlinear optical material (6) to produce wavelength-converted pulses whose center wavelength differs from that of the fundamental pulses. The method comprises the steps of separating the converted pulses from the fundamental pulses, delaying the converted pulses relative to the fundamental pulses, adjusting the polarization of the converted or fundamental pulses, adjusting the energy of the fundamental and converted pulses, superposing the separated fundamental and converted pulses on each other, and allowing the superimposed pulses to pass through a nonlinear optical material (22).

Abstract: An E-Diagnostic system for monitoring a state of an excimer laser or molecular fluorine laser system includes a processing device and an interface. The processing device runs a program for outputting parameter requests to the laser system, receiving parameter values from the laser system in response to the parameter requests, and storing the parameter values such that a record of the state of the excimer or molecular fluorine laser system is kept. The interface signal-couples the processing device with the laser system permitting the outputting of the parameter requests and the receiving of the parameter values between the processing device and the laser system.

Abstract: An on-demand system for generating Iodine gas that is substantially free of contaminants such as water, Carbon Monoxide and Carbon Dioxide includes a solid mixture of oxidizer and fuel having at least one Iodine compound. An ignitor squib is provided to ignite the mixture and thereby generate a contaminant free Iodine gas. Preferably, Iodine Pentoxide (I2O5) is used as the oxidizer and a metal such as Zinc, Tin, Calcium, Magnesium, Aluminum, Silica, Sodium, Potassium, Lithium, Boron, Beryllium, Sodium Azide or Iron is used as the fuel. With this composition, the solid mixture is substantially free of Hydrogen and Carbon compounds and the corresponding combustion gas is free of water, Carbon Monoxide and Carbon Dioxide. The mixture is disposed within a permeable jacket to capture non-gas reaction products generated during combustion such as solid and liquid metal oxides while allowing Iodine gas to pass through the permeable jacket.

Abstract: In a tunable laser source device for branching a light output from a tunable laser source portion 1 to supply to a wavelength measuring device 6 and a wavelength calibrating reference device 5 and then controlling the tunable laser source portion in response to an output of the wavelength measuring device, at least one peak and one notch or two peaks or two notches or more in a measurement interference period of the wavelength measuring device are included between a plurality of reference wavelengths of the wavelength calibrating reference device.

Abstract: A digital controller for a laser driver has a register for storing control data that serve to control an analog circuit of the laser driver. A first interface receives operating data from a local memory. A second interface receives external user data. A control unit controls the data communication between the first and second interfaces and the register. The digital controller thus takes over the trimming process and other communication and control functions of the laser driver. The required information for this is contained in the operating and/or user data.