Abstract: A pre-ionizing arrangement for a gas laser includes two ceramic-jacketed ionizer electrodes extending into an enclosure including spaced-apart slab electrodes of the laser and a lasing gas at reduced pressure. RF power is applied to the dielectric-jacketed ionizer electrodes creating a gas discharge between the dielectric-jacketed ionizer electrodes. This discharge provides ions in the laser gas. The presence of these ions in the lasing gas facilitates ignition of a gas discharge between the slab electrodes for energizing the laser.

Abstract: The present invention provides a gas discharge laser having at least one long-life elongated electrode for producing at least 12 billion high voltage electric discharges in a fluorine containing laser gas. In a preferred embodiment at least one of the electrodes is comprised of a first material having a relatively low anode erosion rate and a second anode material having a relatively higher anode erosion rate. The first anode material is positioned at a desired anode discharge region of the electrode. The second anode material is located adjacent to the first anode material along at least two long sides of the first material. During operation of the laser erosion occurs on both materials but the higher erosion rate of the second material assures that any tendency of the discharge to spread onto the second material will quickly erode away the second material enough to stop the spread of the discharge.

Abstract: A laser and method of producing laser light. The laser and method involve passing a high energy beam of particles through an evacuated chamber. A static electric or magnetic field is established in the chamber in a direction that is essentially perpendicular to the direction of propagation of the beam, but which is a periodically varying field in the direction of propagation. The velocity of the particles and the variation in the field is sufficient to pump the particles into a higher energy state and produce laser light at the output of the chamber.

Abstract: An excimer or molecular fluorine laser system includes a discharge chamber filled with a laser gas mixture at least including a halogen-containing molecular species and a buffer gas, multiple electrodes within the discharge chamber connected to a discharge circuit for energizing the gas mixture, and a resonator for generating a laser beam including an optical component made of MgF2. The optical component made of MgF2 has been previously cleaved along a predetermined plane, such that the refractive indices of the birefringent MgF2 material for orthogonal polarization components of the beam are either at least approximately equal so that the polarization of the beam due to the influence of the birefringent nature of the MgF2 material is not substantially reduced, or are approximately maximum so that at least a portion of one of the components is rejected by the resonator so that the polarization of the beam is increased due to the birefringent nature of the MgF2.

Abstract: A laser discharge unit is provided. The discharge unit includes an elongated electrode plate, an elongated high voltage electrode, and an elongated ground electrode. Both the high voltage electrode and the ground electrode are mounted to the electrode plate in a spaced-apart relationship with their longitudinal axis being substantially parallel to thereby define a gas discharge gap between the electrodes. The gas laser discharge unit may be removably mounted as a module into a gas laser such as an excimer laser.

Abstract: CO2 slab laser having a gas-filled tubular housing, sealed off at both ends by end pieces, which accommodates two overlapping electrodes extending into the tubular housing and mirrors arranged in the region of the electrodes, where each of the two end pieces holds an electrode, the mirrors are arranged stationary relative to the electrodes and the electrodes, jointly with the mirrors, are adjustable relative to one another.

Abstract: A semiconductor laser device including a light reflecting facet positioned on a first side of the semiconductor device, a light emitting facet positioned on a second side of the semiconductor device thereby forming a resonator between the light reflecting facet and the light emitting facet, and an active layer configured to radiate light in the presence of an injection current, the active layer positioned within the resonator. A wavelength selection structure is positioned within the resonator and configured to select a spectrum of the light including multiple longitudinal modes, the spectrum being output from the light emitting facet. Also, an electrode positioned along the resonator and configured to provide the injection current, and a tuning current that adjusts a center wavelength of the spectrum selected by the wavelength selection structure.

Abstract: A film is formed on the discharge parts of the main discharge electrodes. In order to prevent erosion of the discharge parts by the halogen gas contained in the laser gas, a substance that tends not to react with the halogen gas, i.e., a halogen-resistant substance, is used for this film. Furthermore, in order to prevent deformation of the discharge parts by the bombardment and heat of the main discharge, a substance that has a higher hardness than the metal of the main discharge electrodes or a substance that has a higher melting point than the metal of the main discharge electrodes is used for this film. As a result, deterioration of the electrodes can be inhibited, so that a stable laser output can be obtained, and the replacement interval of the electrodes can be extended.

Abstract: A laser and method of producing laser light. The laser and method involve passing a high energy beam of particles through an evacuated chamber. A static electric or magnetic field is established in the chamber in a direction that is essentially perpendicular to the direction of propagation of the beam, but which is a periodically varying field in the direction of propagation. The velocity of the particles and the variation in the field is sufficient to pump the particles into a higher energy state and produce laser light at the output of the chamber.

Abstract: An excimer or molecular fluorine laser system includes a laser chamber filled with a gas mixture at least including a halogen-containing species and a buffer gas, and multiple electrodes with the laser chamber connected to a discharge circuit energizing the gas mixture. The laser chamber is within a laser resonator generating an output beam. The resonator includes a line-narrowing package for reducing a bandwidth of the output beam. The line-narrowing package includes a grating or grism element for use with a highly reflective (HR) and/or an anti-reflective (AR) dielectric coating. The grating may serve as a resonator reflector having a dielectric HR coating. The grating may be disposed before a HR mirror and thus have a dielectric AR or HR coating when the grating is configured in transmission or reflection mode, respectively. The grating may be used as an output coupler, and may be partially reflective with or without a coating.

Abstract: The above discussed and other drawbacks and deficiencies of the prior art are overcome or alleviated by a laser of the present invention. In accordance with the present invention the laser comprises a housing defining a plurality of compartments therein, a folded waveguide disposed within the housing, the folded waveguide defining a plurality of channels having a substantially rectangular cross section for guiding a laser beam, a plurality of electrodes disposed in the plurality of compartments and juxtaposed along opposite surfaces of the waveguide and at least one power supply connected to the plurality of electrodes. The channels having a prescribed width to height ratio for a prescribed channel length for a given Fresnel number. At least one optical housing is provided. The optical housing is mounted to the laser housing, the optical housing including a plurality of beam turning mechanisms disposed within a plurality of compartments accessible for adjusting the beam turning mechanisms.

Abstract: A final stage capacitance of a pulse compression circuit for an excimer or molecular fluorine lithography laser system is provided by a set of peaking capacitors connected through a first inductance to the electrodes and a set of sustaining capacitors connected to the electrodes through a second inductance substantially greater than the first inductance. Current pulses through the discharge are temporally extended relative to current pulses of a system having its final stage capacitance provided only by a set of peaking capacitors connected to the electrodes via the first inductance. An amplified spontaneous emission (ASE) level in the laser pulses is reduced thereby enhancing their spectral purity.

Abstract: Fluorine gas discharge laser electrodes and electrode systems are disclosed that may comprise a plurality of current return tangs extending for less than the respective length of the second elongated gas discharge electrode. In addition disclosed are electrodes that may comprise a first discharge shaping magnet mounted in a first elongated gas discharge electrode and a second discharge shaping magnet mounted in a second elongated gas discharge electrode. This may also comprise at least one of the first and second gas discharge electrodes has imbedded therein a first and a second auxiliary field creating magnet.

Abstract: The present invention relates to a gas laser with a high-voltage electrode 12 and a ground electrode 14, which electrodes 12, 14 are disposed relative to each other so as to form a discharge gap 16 between them, and with high voltage generating means including a circuit having at least one storage capacitor and at least one secondary capacitor 18, 20, said secondary capacitor 18, 20 being disposed in the area of said high-voltage electrode 12 within a discharge chamber 32 filled with laser gas. Said secondary capacitor 18, 20 includes at least one external surface 28, 28′ oriented towards said high-voltage electrode 12 and made of a material which is inert with respect to said laser gas, which external surface 28, 28′ forms at least one boundary surface of a flow channel 26, 26′ for said laser gas.

Abstract: A dedusting unit for a laser optical element is provided. The dedusting unit comprises a high-voltage duct comprising a high-voltage conducting core having a first end and a second end and an insulator element disposed around the core. The first end of the core is connectable to a high voltage power supply and the second end of the core is electrically connected to a wire loop. The dedusting unit may be used in connection with a variety of gas lasers. In use, the dedusting unit is mounted to the laser tube so that the wire loop is disposed inside the gas laser tube in proximity to an optical element to be protected from dust. The dedusting unit is further mounted so that the wire loop is transverse to the resonating path of the laser light within the laser tube so that the resonating laser light may pass through the wire loop without being obstructed by the wire loop. A method for installing the dedusting unit to protect a laser optical element in a gas laser is also provided.

Abstract: An electrode structure includes a conductive film 24c formed on a base substrate 10 through an insulation film. The insulation film comprises a plurality of poles 36 of polyimide, a first film 38 formed on the side surfaces of the poles and formed of an insulation material of a high hardness than polyimide, and a second film 40 of polyimide buried among the plural poles with the first film formed on the side surfaces thereof. Because of the first film of an insulation material having high hardness formed on the side surfaces of the poles of polyimide, even when a strong force is applied upon the bonding, the poles are prevented from being distorted, and the conductive film is protected from peeling off. Because of the thick polyimide layer below the conductive film, a parasitic capacity between the conductive film and the lower layer can be small, whereby radio-frequency signals can be used.

Abstract: The invention provides a discharge electrodes connecting structure for a laser apparatus in which a thickness of the return plate is set to be within an optimum range, and a laser apparatus employing the same. Accordingly, a laser apparatus is provided with a laser chamber (2) sealing a laser gas, a pair of anode (5A) and cathode (5B) provided within the laser chamber in an opposing manner, generating a discharge so as to excite a laser gas flowing therebetween and oscillating a laser beam, a conductive anode base (6) holding the anode, an insulative cathode base (8) holding the cathode, and a return plate (9) electrically connecting the anode base to the laser chamber so as to supply a current to the anode. A thickness (t) of the return plate is set to be equal to or more than 100 &mgr;m and equal to or less than 500 &mgr;m, and the return plate is arranged substantially in parallel to a gas flow of the laser gas flowing between the discharge electrodes.

Abstract: An electrically-pumped vertical-cavity surface-emitting laser (VCSEL) has multiple active regions. Embodiments of the invention provide an electrically-pumped VCSEL having a number of different p-i-n junction and electrode arrangements, which, in various embodiments, allow independent biasing of the multiple active regions, and, in other embodiments, allow simplified electrical connections.

Abstract: The invention relates to an High Repetition Rate UV Excimer Laser which includes a source of a laser beam and one or more windows which include magnesium fluoride. Another aspect of the invention relates to an excimer laser which includes a source of a laser beam, one or more windows which include magnesium fluoride and a source for annealing the one or more windows. Another aspect of the invention relates to a method of producing a predetermined narrow width laser beam.

Abstract: Arcing can be minimized in a discharge chamber of an excimer or molecular fluorine laser system by utilizing an improved electrode structure. An electrode structure can include at least one ceramic spoiler positioned near the discharge region of the electrode. An insulating ceramic spoiler can reduce the effective area over which arcing can occur, and can reduce the likelihood of arcing by improving the flow of gas between the electrodes, such as by allowing for design flexibility and reducing the necessary height of a nose portion used to control the discharge area of the electrode. An improved blower design, which can utilize improved bearings and a dry film lubricant, can help to circulate the laser gas between the electrode structures, such as at a speed of at least 30 m/s in order to operate the laser at repetition rates of 4 kHz or higher.

Abstract: A preionization device for a gas laser includes an internal preionization electrode having a dielectric housing around it such that the preionization device is of corona type. The internal electrode connects to advantageous electrical circuitry, preferably external to the discharge chamber via a conductive feedthrough. The circuitry reduces the voltage across the dielectric tube of the preionization unit to reduce over-flashing at tube ends and oscillations due to residual energies stored in the dielectric. A semi-transparent mesh electrode between the preionization unit and the discharge area prevents field distortions and discharge instabilities.

Abstract: A gas laser comprises a pair of elongated electrodes arranged to define a discharge region between two opposing surfaces of said elongated electrodes, wherein the discharge region defines a longitudinal axis, a wide axis and a narrow axis. The gas laser further includes a lasing gas disposed in said discharge region and an excitation means for energizing the electrodes to excite the lasing gas. A first mirror is arranged in front of a first end of the pair of elongated electrodes, wherein the first mirror is spaced apart from the first end along the longitudinal axis by a first distance, and a second mirror is arranged in front of a second end of the pair of elongated electrodes. Moreover, the two opposing electrode surfaces define an electrode curvature, respectively, that is adapted such that a wave front of the a fundamental transverse radiation mode with respect to the narrow axis substantially coincides with a mirror curvature of the first mirror at the first distance.

Abstract: Electrodes for a fluorine gas discharge laser are disclosed which may comprise a crown straddling the centerline axis between the pair of side walls and the pair of end walls, comprising a first material, forming at least a portion of the discharge region of the electrode; the crown in traverse cross section having the shape of the upper half of a canted ellipse rotated in the preionizer direction, such that a tangent to the short centerline axis of the ellipse forms an angle with the horizontal. Another embodiment may comprise an anode blade having a top portion and a first and second sidewall portion each intersecting the top portion; the anode blade being formed with the shape in cross section of the top portion being curvilinear and intersecting the generally straight potions of each of first and second sidewall portions along a radius of curvature and with the top portion beveled away from an asymmetric discharge side of the anode.

Abstract: A fluorine gas discharge laser electrode for a gas discharge laser having a laser gas containing fluorine is disclosed which may comprise a copper and copper alloy cathode body having an upper curved region containing the discharge footprint for the cathode comprising copper and a lower portion comprising a copper alloy, with the facing portion of the electrode if formed in a arcuate shape extending into straight line portions on either side of the arcuate portion, the straight line portions terminating in vertical straight sides, with the boundary between the copper including at least the arcuate portion, the electrode may comprise a bonded element machined from two pieces of material the first made of copper and the second made of a copper alloy bonded together before machining.

Abstract: Truncated ridge waveguide for all-metal gas laser excitation according to present invention consists of a metal tube and a pair of endplates forming a vacuum envelope for containing a laser gas, a laser resonator mirrors placed on the endplates at the opposite ends of the tube and at least one elongated metal ridge electrode located within and conductively connected to the metal tube by at least one metal post to define a truncated ridge waveguide. The tube and the ridge electrode are shaped and positioned so as to define at least one elongated laser bore channel and a low thermal resistance and high capacitance ridge-to-tube gap therebetween. The ridge electrode and metal posts form truncated ridge to increase the ridge waveguide structure inductance, which together with high capacitance of the electrode-to-tube gap decreases the resonant frequency from the microwave band into the VHF band (30-300 MHz), which is the most suitable for CO2 laser excitation.

Abstract: A gas discharge laser having an elongated cathode and an elongated anode with a porous insulating layer covering the anode discharge surface. A pulse power system provides electrical pulses at rates of at least 1 KHz. A blower circulates laser gas between the electrodes at speeds of at least 5 m/s and a heat exchanger is provided to remove heat produced by the blower and the discharges. In preferred embodiments at least a portion of the anode is comprised of lead, and fluorine ion sputtering of the anode surface creates the insulating layer (over the discharge surface of the anode) comprised in large part of lead fluoride. In a particular preferred embodiment the anode is fabricated in two parts, a first part having the general shape of a prior art anode with a trench shaped cavity at the top and a second part comprised of lead rich brass and disposed in the trench shape cavity.

Abstract: The present invention is a device for avoiding sliding discharges in pre-ionization in a gas laser with corona discharge. The invention uses a pair of main electrodes provided in a closed gas discharge volume, and at least one pair of corona electrodes which are arranged in the immediate vicinity of the pair of main electrodes. The individual electrodes, which include a tube-like sheathing of dielectric material, are designed to be open on both ends and contain an electrically conducting rod, or core, introduced into the interior and projecting beyond the sheathing. The invention is distinguished by the provision that the material selection, the shaping of various elements associated with the gas discharge volume, or a combination of material selection and shaping is made in such a way that a specific capacitance per unit area is provided in the surface region on both ends of the sheathing is lower than the capacitance in the central region of the sheathing between its both ends.

Abstract: Internal mirror sputtering metal ion lasers are disclosed which employ laser mirrors and a resonator internal to and integral with the laser plasma tube. Preferred lasers use silver, copper, gold and other metals individually or in combination as optically active materials and buffer gases of helium, neon, argon and other noble gases. Laser mirrors are utilized to enhance or reject selected combinations of emission wavelengths. Because of the rapid response time of these lasers, they may be employed as quasi-CW devices with laser output pulse widths ranging from a few microseconds to hundreds of microseconds and with very low input power ranging from a few watts to about 500 watts. The disclosed lasers approach the size, weight, power consumption, and cost of a helium-neon laser while providing quasi-continuous output up to hundreds of milliwatts at a wide range of wavelengths from about 200nm in the deep ultraviolet to about 2000nm in the middle infrared.

Abstract: The present invention provides a gas discharge laser having at least one long-life elongated electrode for producing at least 12 billion high voltage electric discharges in a fluorine containing laser gas. In a preferred embodiment at least one of the electrodes is comprised of a first material having a relatively low anode erosion rate and a second anode material having a relatively higher anode erosion rate. The first anode material is positioned at a desired anode discharge region of the electrode. The second anode material is located adjacent to the first anode material along at least two long sides of the first material. During operation of the laser erosion occurs on both materials but the higher erosion rate of the second material assures that any tendency of the discharge to spread onto the second material will quickly erode away the second material enough to stop the spread of the discharge.

Abstract: Electric field easing members (corona rings) for easing concentration of electric fields caused at edges of a core are disposed between the core and a winding to form a gap so to allow the presence of a cooling medium (insulating oil) between the top and bottom surfaces of the core and the electric field easing members. Thus, pressboards between the core and the electric field easing members become unnecessary, a wire-wound apparatus can be prevented from having a short service life due to the degradation of the pressboards, and the pressboards can be made to have a long service life because the electric field easing members are not heated by thermal conduction from the core.

Abstract: The present invention provides a gas discharge laser having at least one long-life elongated electrode for producing at least 12 billion high voltage electric discharges in a fluorine containing laser gas. In a preferred embodiment at least one of the electrodes is comprised of a first material having a relatively low anode erosion rate and a second anode material having a relatively higher anode erosion rate. The first anode material is positioned at a desired anode discharge region of the electrode. The second anode material is located adjacent to the first anode material along at least two long sides of the first material. During operation of the laser erosion occurs on both materials but the higher erosion rate of the second material assures that any tendency of the discharge to spread onto the second material will quickly erode away the second material enough to stop the spread of the discharge.

Abstract: A device for use with a repetitively pulsed gas laser provides self-initiated UV preliminary ionization of the active volume of a laser, which has extended high-voltage and grounded electrodes disposed parallel to one another, to which peaking capacitors distributed along the length of the electrodes are connected in a low-inductance manner. The low-voltage contacts of the peaking capacitors are either connected directly to the grounded electrode or, if this connection is interrupted, dielectric plates are inserted that are disposed either on one side or on both sides of the grounded electrode. If the capacitors are charged rapidly, a surface discharge which effects UV pre-ionization of the volume of the main discharge and is uniformly distributed over the whole surface of the dielectric plates is produced on the surface of the dielectric plates.

Abstract: Apparatus and method for controlling the length of a laser cavity comprises a laser diode that is configured to produce a beam of energy, the laser diode has a first end and an output end, the first end being in optical communication with a highly reflective mirror. A wave guide having a receiving end and a transmission end is also provided, with the wave guide being comprised of an electro-optical material, wherein the receiving end is in optical communication with the output end, and the transmission end is in optical communication with an output coupler. A plurality of electrodes are disposed along a longitudinal axis of the wave guide, wherein the voltage on each electrode is independently controlled to alter the index of refraction of the wave guide at a position adjacent each electrode. A polarizer is also provided with respect to the transmission end, with the polarizer configured to attenuate the beam of energy.

Abstract: An excimer laser with a laser chamber containing a circulating laser gas containing fluorine and a set of long life electrode structures. At least one of the electrode structures has an erosion pad and a cross section shape designed to provide in conjunction with other chamber structure a gradual increasing flow cross section between the discharge region and the circulating tangential fan blade. In a preferred embodiment, electrode lifetime is increased by annealing the erosion rod after it is are machined. This annealing relieves the surface stress caused by the machining operation and reduces the exposed metallic grain boundary length per unit area on the surface of the electrodes, which provides substantial reduction in erosion caused by fluorine chemical attack. Annealing after machining also reduces the stress throughout the bulk of the electrode material. In preferred embodiments the anode is a copper-aluminum alloy and the cathode is a copper-zinc alloy.

Abstract: A corona preionization electrode unit for use in gas laser apparatus, wherein the electric field for corona discharge is concentrated, and ultraviolet radiation is not blocked, and further the laser gas stream is not obstructed, thereby allowing efficient, stable and uniform corona preionization. The corona preionization electrode unit is disposed in a gas laser apparatus together with a pair of main discharge electrodes for ionizing and exciting a laser gas. The corona preionization electrode unit includes a first electrode covered with a dielectric material and a second electrode placed in contact with the outer surface of the dielectric material around the first electrode. The corona preionization electrode unit is positioned in the vicinity of either one of the main discharge electrodes. The second electrode is a plate-shaped member having a straight edge contacting at least the outer surface of the dielectric material.

Abstract: A laser has at least two coaxial electrode tubes spaced apart to provide a laser cavity therebetween and a cooling system including cooling coils about the outer surface of the outer electrode and about the inner surface of the inner electrode and in heat exchange contact therewith. Support pipes are provided about the outside of the outside cooling coil and about the inside surface of the inner cooling coil. The cooling coils are deformed into improved heat exchange contact with the electrode tubes by internal pressure and may be softened by annealing or the like before the application of the deformation pressure.

Abstract: A preionization device for a gas laser comprises an internal preionization electrode having a dielectric housing around it and an external preionization electrode displaced from the dielectric housing by a small gap. The dielectric housing includes two cylindrical regions of differing outer radii of curvature. An open end of the housing has a larger radius of curvature than the other end which is closed. The internal electrode connects to circuitry external to the discharge chamber via a conductive feedthrough which penetrates through the housing. The external circuitry prevents voltage oscillations caused by residual energy stored as capacitance in the dielectric housing. The external preionization electrode, which is connected electrically to one of the main discharge electrodes, is formed to shield the internal preionization electrode from the other main discharge electrode to prevent arcing therebetween.

Abstract: The present invention relates to a semiconductor laser device having a protective coating with a high-reliability formed on an end surface, and to a method for manufacturing the same. According to the present invention, in forming a semiconductor laser device, an electrode comprising Au is patterned so that the electrode does not exist in the vicinity of a light emitting end surface. Thereby, even when an Si film is formed on the light emitting end surface, the Si film is prevented from contacting with the light emitting end surface. In addition, after patterning the electrode, an insulating film (a silicon nitride film) is formed on the electrode for preventing the Si in the protective coating on the end surface from contacting with Au in the electrode, even when the Si film contacts with a surface of the electrode.

Abstract: Disclosed is a gas laser utilizing radio frequency excitation in the area of sonic or supersonic/subsonic transfer gas flow. The laser uses various types of gases and mixtures of gases as the active medium using radio frequency excitation. The gas is supplied into a supersonic nozzle for acceleration of the active gaseous flow to supersonic or deceleration to high subsonic speeds in order to provide intensive dynamic cooling of the active gas medium. The gas is excited using radio frequency excitation in the critical area of the supersonic nozzle or downstream therefrom. The radio frequency action and excitation can also occur within the optical resonator region which is located within the supersonic area of the nozzle.

Abstract: A discharge electrode for a laser device which can cause stable main discharge to occur is provided. To this end, the discharge electrode includes a cathode base (8) made of an insulating material for sealing up a chamber opening (7) provided in a laser chamber (2) for containing laser gases, a cathode (5) attached to the cathode base (8) with a bottom surface (5A) of the cathode (5) in contact therewith, and a plurality of high-voltage feeder rods (12) disposed in a longitudinal direction, penetrating through the cathode base (8) from an outside of the laser chamber (2) which supplies a high-voltage current to the cathode (5), in which an O-ring groove (22) for sealing in the laser gases is formed on the bottom surface of the cathode (5) to surround a plurality of holes (24) for fixing the high-voltage feeder rods (12) disposed on the bottom surface of the cathode (5).

Abstract: An optical pulse generator, consisting of a semiconductor device and an optical output assembly. The semiconductor device includes an optically-active region having a gain section and a saturable absorber (SA) section, which are adapted to generate coherent optical pulses. The device also includes an output facet for coupling therethrough of the optical pulses generated in the optically-active region, and an SA electrode for application of a radio-frequency (RF) modulation of a desired frequency to the SA section. The optical output assembly is optically coupled to the output facet of the semiconductor device so as to partially reflect the coherent optical pulses within a predetermined wavelength range.

Abstract: A preionization device for a gas laser comprises an internal preionization electrode having a dielectric housing around it and an external preionization electrode displaced from the dielectric housing by a small gap. The dielectric housing includes two cylindrical regions of differing outer radii of curvature. An open end of the housing has a larger radius of curvature than the other end which is closed. The internal electrode connects to circuitry external to the discharge chamber via a conductive feedthrough which penetrates through the housing. The external circuitry prevents voltage oscillations caused by residual energy stored as capacitance in the dielectric housing. The external preionization electrode, which is connected electrically to one of the main discharge electrodes, is formed to shield the internal preionization electrode from the other main discharge electrode to prevent arcing therebetween.

Abstract: A laser system and method having an output laser beam uses an gain medium with one or more output beam transverse profile tailoring (OBTPT) longitudinal strips to tailor the transverse profile of the output laser beam to a desirable shape such as having a symmetrical profile transverse to the direction of propagation of the output laser beam. The laser system has two reflector systems on opposite ends in the long z-axis dimension of the gain medium to form a resonator that outputs the output laser beam following the same long z-axis dimension. In some embodiments the gain medium has a narrow y-axis dimension and a wide x-axis dimension. In these embodiments the OBTPT longitudinal strips have lengths running the long z-axis dimension, widths running the wide x-axis dimension and thicknesses running the narrow y-axis dimension of the gain medium. The widths of the OBTPT longitudinal strips are generally chosen with respect to coupling width of the output laser beam.

Abstract: The invention provides a discharge electrodes structure which can be easily replaced and adjustable a distance between the discharge electrodes, and a laser apparatus employing the discharge electrodes. Accordingly, the laser apparatus is provided with a pair of anode (5A) and cathode (5B) provided within a laser chamber (2) for sealing a laser medium in an opposing manner, generating a discharge so as to excite the laser medium and oscillating a laser beam, a conductive anode base (6) holding the anode, an insulative cathode base (8) placed so as to close an opening portion (4) provided in the laser chamber and holding the cathode, a return plate (9) suspending the anode base from the cathode base so as to supply a current to the anode, and an anode support bar (23) for connecting the cathode base to the anode base so as to suspend the anode from the cathode base.

Abstract: A gas laser and a dedusting unit thereof are provided. The gas laser comprises a tube containing a gas mixture including a laser gas and preferably a buffer gas. The tube preferably comprises a cylindrical inner wall. A discharge unit is inserted into the tube and has two elongated electrodes defining an electrical gas discharge gap therebetween for providing an electric gas discharge between said electrodes to generate laser light. A circulation means is included in the tube for generating a gas flow within the tube that passes through the discharge gap. A dedusting unit is mounted along the inner cylindrical wall of the tube in such a manner that only a bypass flow which is a part of the gas flow within the tube passes through the dedusting unit.

Abstract: A CO2 laser utilizing combination of direct current (DC), radio frequency (RF) discharges together with an unstable resonator is disclosed. The combined use of the combination of DC and RF discharges in the laser apparatus allows to provide high power output radiation within a relatively compact design of the apparatus. Consequently, the laser operating efficiency is increased, with a significant lowering of required excitation voltages, and a substantial reduction in excitation hardware. The laser apparatus of the present invention may have durable and reliable construction that is relatively easy and cheap in manufacturing.

Abstract: Electrodes comprised of spinodal copper alloys. Applicant's tests have shown erosion rates of these alloys under certain environmental conditions are a factor of 5 or more lower than erosion rates of similar prior art copper alloys. In one application, the erosion of spinodal electrodes was at least an order of magnitude lower than the prior art material. A preferred application of these electrodes are as electrodes in excimer lasers which utilize a circulating laser gas containing fluorine. A preferred spinodal copper alloy is a copper-tin-nickel alloy known as spinodal bronze. These alloys are prepared using spinodal decomposition. This material forms atomic layers several atoms thick. The spinodal decomposition process permits atoms of one kind to concentrate to an extent while maintaining a relatively uniform crystal structure.

Abstract: A thin film laser emitting device includes a Bragg reflector including a recess and one or more diffraction gratings provided around the recess, a thin film laser layer formed in the recess, for generating lights, the lights being reflected by the diffraction gratings, a pair of electrodes, provided in the recess to have the thin film laser layer therebetween, and a laser emitting means, provided at a portion of the gratings, for emanating the reflected lights.

Abstract: A gas discharge laser having a laser chamber with two elongated electrode elements, each having a discharge section having an optimum array of discharge peaks and sputter cavities. The sputter cavities provide sputter metal ions to contribute to a plasma between the electrodes and support a glow-type discharge. The peaks provide very high fields which produce a very large number of filament-type discharges. The electrodes erode gradually but since the discharge region is confined to the array of discharge peaks and sputter cavities, the shape of he discharge remains approximately constant for billions of pulses. A pulse power system provides electrical pulses of at least 2J at rates of at least 1 KHz. A blower circulates laser gas between the electrodes at speeds of at least 5 m/s and a heat exchanger is provided to remove heat produced by the blower and the discharges.

Abstract: A laser for an excimer or molecular fluorine laser includes an electrode chamber connected with a gas flow vessel and having a pair of main electrodes and a preionization unit each connected to a discharge circuit. A spoiler is provided within the electrode chamber and is shaped to provide a more uniform gas flow through the discharge area between the main electrodes, to shield one of the preionization units from one of the main electrodes, and to reflect acoustic waves generated in the discharge area into the gas flow vessel for absorption therein. A spoiler unit may include a pair of opposed spoiler elements on either side of the discharge area. One or both main electrodes includes a base portion and a center portion which may be a nipple protruding from the base portion. The center portion substantially carries the periodic discharge current such that the discharge width is and may be significantly less than the width of the base portion.