Abstract: A pulsed transversely excited gas laser device includes a pair of main electrodes having main surfaces opposing each other across a main discharge gap and extending along the optical axis of the laser. A corona discharge preionizer for radiating ultraviolet radiation is substantially accommodated within a recess formed on the main surface of one of the main electrodes at an upstream side of the foot of the main discharge 3. The corona discharge preionizer is separated from the inner wall and bottom surface of the recess except at a surface portion thereof which is in contact with a projection extending sideways from a side wall of the recess next to the main discharge. The corona discharge generated over the preionizer radiates ultraviolet radiation to preionize the laser gas.

Abstract: By dissipating a reverse voltage energy occurring on the pulse generation capacitor (4) of a pulse laser apparatus through the diode (11) connected in parallel with this pulse generation capacitor (4), arc or streamer becomes not occurring, and hence the lifetime of the main discharge electrodes become long and a high-repetition rate oscillation becomes possible.

Abstract: A pulsed laser according to the present invention comprises a charge terminal, mutually-opposing first and second main discharge electrodes, a pulse generation capacitor connected between the first main electrode and the charge terminal, a plurality of peaking capacitors connected in parallel between the first and second main discharge electrodes, and a plurality of diodes connected in parallel with the plurality of peaking capacitors and oriented to suppress reverse-bias components of main discharge current flowing between the first and second main discharge electrodes. Thereby, reverse current flowing between the first and second main discharge electrodes can be minimized without sacrificing laser oscillation efficiency.

Abstract: A wavelength monitor/stabilizer for narrowly controlling the bandwidth of laser; the monitor/stabilizer uses parameters Q, F or G derived by measuring diameters of interference fringes given by the beam of the wavelength-controlled narrow bandwidth laser e.g. excimer laser and those given by the reference light e.g. of a mercury lamp. The controlling is made by controlling the parameter to be in a predetermined range. An image sensing unit for detecting the interference fringes are splitted into plural image sensors with adjustable distance for enabling more rapid measurement by skipping the in-between part.

Abstract: At least the opposing surface portions of the main electrodes of an excimer laser device are covered with materials which are resistive to chemical etching than nickel. The etching resistive material may be a platinum based alloy containing rhodium, ruthenium, iridium, or osmium; a nickel based alloy containing gold, platinum, rhodium, ruthenium, iridium, or osmium; or rhodium, ruthenium, iridium, or osmium. Thus, an excimer laser device is realized by which the lives of the electrodes and the laser gas are prolonged.

Abstract: A method and apparatus for stabilizing the wavelength in a laser. The apparatus includes a first and second etalon for fine and rough tuning, respectively, of a laser oscillator. The output power and wavelength of the laser beam, for example, can be used to adjust these etalons to provide a constant output power and to counteract the change in etalon characteristics due to heat.

Abstract: A discharge exciting pulse laser device such as an exima laser device. The laser device is capable of accelerating the timing of rise of the voltage between an auxiliary electrode and one of main electrodes without decreasing a discharge start voltage between the main electrodes, so that the laser output power is increased and the laser oscillation efficiency is improved.

Abstract: A multi-player type video game playing system permits a plurality of players to play and enjoy a game within the common game space. The video game has a cylinder-shaped screen; a plurality of projectors arranged and allocated to project a game scene continuously extending around the entire circumference of the cylindrical screen; a plurality of players' operating sections arranged radially toward the screen; and an image processor for computing a game scene to be projected onto the screen in accordance with input signals from the players' operating sections and a predetermined game program. The image signals representative of the computed game scene are supplied to the projectors to form the game scene continuously extending around the entire circumference of the screen, whereby any one of the players can face and observe a transversely widened game scene covering the entire field of view for that player such that all the players can enjoy the game with increased reality.

Abstract: A laser apparatus comprising a Fabry-Perot etalon for selecting a laser oscillation wavelength and a wavelength monitor means for monitoring a laser beam taken out from a laser oscillator whose wavelength is variable, whereby the pressure at the gap in the Fabry-Perot etalon is adjusted on the basis of a signal output from the wavelength monitor means. In order to adjust the pressure at the gap the Fabry-Perot etalon is hermetically sealed in a vessel containing a gas and the gas pressure is controlled on the basis of the output signal.

Abstract: Methods of controlling the wavelength and output power of a laser device with two intracavity etalons are disclosed, together with a wavelength monitor capable of detecting sidebands. A method is characterized by the usage of hot/cold parameter K which takes two values 0 and 1 indicating the cold and hot state of the device, respectively. The parameter K, which is reset to 0 at the start, is set to 1 when the laser beam is stabilized; it is reset to 0, whenever the lasing pause exceeds a predetermined time length. Preparatory starting steps are performed or omitted at the start, depending on the value of K. Another method is characterized by the adjustment of the intracavity etalons during the lasing pauses, in accordance with exponential functions with thermal time constants. The sideband detecting wavelength monitor comprises a single etalon whose free spectal region FSRm is selected with respect to that, FSR.sub.

Abstract: A laser wavelength is stabilized by deriving a portion of laser beam emitted from a wavelength variable laser oscillator, spectroscopically processing the laser beam portion by means of a wavelength monitor mechanism, measuring a spatial intensity distribution of the spectroscopically processed beam portion, spectroscopically processing light having a specific wavelength and measuring a spatial intensity distribution thereof, analyzing the measured spatial intensity distribution of the spectroscopically processed beam portion on the basis of the measured spatial intensity distribution of the spectroscopically processed light having the specific wavelength, and controlling wavelength of the laser oscillator according to a result of the analysis.

Abstract: A discharge excitation type short pulse laser device which is constructed with first and second main electrodes disposed in confrontation with the direction of the laser beam axis as their longitudinal direction, an auxiliary electrode provided on the rear surface part of the second main electrode and opposed to the second main electrode through the dielectric member, a pulse circuit for applying a pulse voltage across the first and second main electrodes, and a circuit for applying a voltage across the auxiliary electrode and the second main electrode, the circuit forming a part of the pulse circuit, or being independent of the pulse circuit, wherein the second main electrode is made of an electrically conductive material having a plurality of apertures therein, the second main electrode and the dielectric member are disposed in tight adhesion each other, and the second main electrode is thinly formed to enable creeping discharge to be produced on the surface of the dielectric member, thereby distributing el