Abstract: A laser gas used in a rare gas fluoride excimer laser is efficiently refined with little loss of the principal rare gas such as Ar, Kr or Xe by sequential contact of the laser gas first with a reactive metal, e.g. Si or Fe, for conversion of the fluorine source gas such as F.sub.2 or NF.sub.3 to a metal fluoride, then with a solid alkaline compound, e.g. Ca(OH).sub.2, for conversion of gaseous fluorides to solid metal fluorides, next with zeolite which is adsorbent of most of the remaining impurities and finally with an alkaline metal, e.g. Ca or Na, for decomposition of CF.sub.4 to form a solid metal fluoride and carbon. CF.sub.4 is formed during operation of the excimer laser by reaction of fluorine with a fluororesin used as electrical insulator in the laser apparatus, and accumulation of CF.sub.4 in the laser gas caused significal lowering of the laser output power.

Abstract: An iodine chemical laser is disclosed comprising: a laser cavity; a combustion chamber; a first injector injecting into said combustion chamber an iodine compound as a fuel; a first supply means for supplying the fuel to said first injector; a second injector for injecting F.sub.2 and NF.sub.3 into said combustion chamber; a second supply means for supplying said F.sub.2 and NF.sub.3 to said second injector; combustion initiating means for initiating combustion of the mixture fuel-combustion supporter in said combustion chamber; a supersonic nozzle for extracting products resulting from said combustion fuel-combustion supporter and supplying them into said laser cavity; supply means for supplying singlet oxygen into said laser cavity at the same time as said combustion resulting products; said fuel being in excess with respect to stoichiometric proportions corresponding to said combustion, richness .phi. of said iodine compound fuel with respect to said stoichiometric proportions being 0.5<.phi.<2.

Abstract: An excimer laser apparatus with an HCl generator. The HCl generator is constructed so that HCl gas is generated by the reaction of a fixed concentration of hydrogen gas in the laser gas mixture with an equivalent amount of metallic chlorides. The reaction occurs at a preset temperature, and the metallic chlorides may be either in the laser gas chamber or in the circulation line of the laser gas. Consequently, the HCl required for laser generation is continuously formed by the H.sub.2 reduction of the metallic chlorides. The HCl loss due to the formation of impurities is automatically replenished to maintain a constant concentration of HCl in the laser gas, which results in stable laser generation. This simplified and dependable excimer laser apparatus can be operated continuously for a long time, since it is not necessary to measure and replenish the HCl lost due to the formation of impurities. Furthermore, instead of using a bomb for the highly toxic HCl gas, a bomb for He mixed with H.sub.

Abstract: A modified laser tube including a second pinch off tube or port for flowing argon and krypton gas through the laser for processing to remove contaminants to improve performance of new and used tubes such as ALC 60X argon ion lasers. Lasing discharge is maintained during processing to release contaminants for removal by plasma scrubbing of the laser bore. A magnetic field is applied and rotated in a plane perpendicular to the laser during discharge to enhance contamination release during plasma scrubbing. Preliminary cathode activation, control of gas flow rates and tube power as well as alternating of argon and krypton gas controls the contaminant release rate to prevent recontamination of the laser by released contaminants before removal.

Abstract: A carbon dioxide (CO.sub.2) waveguide laser is used to provide coherent infrared radiation. The mixture of gases in the laser includes helium, nitrogen, carbon dioxide, carbon monoxide, xenon and heavy hydrogen (deuterium). Carbon dioxide is the gain medium of the laser. During operation of the laser, a significant fraction of the CO.sub.2 dissociates to CO and O.sub.2. In the present invention, deuterium (D.sub.2) in the presence of excess CO catalyzes the recombination of CO and O.sub.2 back to CO.sub.2, thus yielding significantly increased power output from the laser. The presence of D.sub.2 also sustains a long sealed life from the CO.sub.2 laser at an enhanced power output level.

Abstract: A gas laser device for effecting a laser oscillation while circulating a laser gas therein includes a laser gas supply unit (5), a gas supply valve (6) arranged at an outlet of the laser gas supply unit, an exhaust unit (9) for exhausting the laser gas from a discharge tube (1), a pressure sensor (7) for detecting the pressure in the discharge tube (1), and a control apparatus (10) which detects a pressure drop in the discharge tube (1) by the pressure sensor (7) and opens the gas supply valve (6) to fill the discharge tube (1) with the laser gas to a predetermined pressure level when operation of the gas laser device is stopped. Thus the pressure in the discharge tube (1) is always higher than the pressure in the gearbox (4a), to prevent the oil in the gearbox (4a) from entering the discharge tube (1).

Abstract: In a piping system for a laser oscillator (1), there are provided gas medium circulating pipes (211, 212, 213, 214) connected with a laser discharge tube (11) for circulating the gas medium therethrough, a gas medium circulating pump (23) arranged in the gas medium circulating pipes, a gas medium supply pipe (217, 218) for supplying a gas medium to the gas medium circulating pipes, a gas medium exhaust pump (24) arranged in a gas medium exhaust pipe and driven by a drive device for exhausting the gas medium in the laser discharge tube and the gas medium circulating pipes, and a control device (7) for controlling the operation of the laser oscillator piping system, the control device receiving a signal from the pressure sensor and generating a signal to be supplied to the gas medium exhaust pump and a signal to be supplied to a display device (6).

Abstract: A control circuit for a pulsed gas laser comprises a plurality of sensors 9, 12, a plurality of control members (e.g. 10) and a central control unit 13. Associated sensors and control members, i.e. sensors which measure a parameter variable by the associated control member, are connected jointly to modules 7, 8, 11 and each module comprises at least one microprocessor; the modules are connected by means of optical waveguides 20 in series in a ring to the central control unit 13. The arrangement makes it possible to save complicated electromagnetic shielding, provides easy fault tracing and simple expansion of the control circuit by further modules.

Abstract: A closed loop carbon dioxide laser system includes a catalytic converter in the form of a conduit with an annular recess which is filled with a catalyst of platinum-plated alumina pellets that are externally heated.

Abstract: The performance of a carbon monoxide laser is improved by coating the walls of the surface facing the discharge with a precious metal chosen from the group consisting of gold, silver, platinum, palladium, rhodium and iridium. The precious metal coating is configured into segments which do not interfere with the electrical discharge.

Abstract: A fast axial flow laser includes a vessel which houses heat exchangers and a pump which imparts the pumping action throughout the laser. Only one housing is necessary and this housing can also be used as an optical bench for the resonator. In one embodiment a positive displacement rotary pump is utilized and a retoreflector included to mount three fold mirrors. In the folded configuration the retroreflector provides angular stability in any two orthogonal planes parallel to the laser beam.

Abstract: The invention relates to a plasma apparatus where plasma is generated utilizing microwave discharge and laser excitation is performed and plasma processing is performed. More specifically, in a plasma apparatus where a microwave from a microwave oscillator is transmitted through a microwave transmission path to a microwave circuit, and plasma is generated by a microwave discharge within the microwave circuit, a plasma generating medium for generating the plasma is filled in a space formed between a conductor wall constituting a part of the microwave circuit and a dielectric installed opposite to the conductor wall, and the microwave circuit forms microwave mode having an electric field component orthogonal to the boundary between the dielectric and the plasma.

Abstract: A directly heated catalyst 10 is comprised of an electrically conductive ceramic substrate 12 having a catalytic coating 14 applied to at least an outer surface thereof. In an illustrative embodiment of the invention the catalytic coating is a noble metal or non-noblemetal coating. In accordance with one embodiment of the invention a high surface area form of platinum (Platinum Black) is deposited upon a ceramic substrate, such as a substrate comprised of SiC or SnO.sub.2. The coating is brought to its activation temperature by resistively heating the substrate with an electrical current. A temperature sensing device (20, 40), such as a thermocouple or a thermostat, may be coupled to the catalyst structure for sensing the temperature of the catalyst to control the heater current supplied to the substrate. The catalyst is shown to be useful for CO.sub.2 gas lasers.

Abstract: A method of stabilizing an operation of a continuous axial gas laser including at least one gas flow tube system comprising at least one excitation tube, and a gas flow circulation arrangement connected to the gas flow tube system to generate a gas flow therethrough. The gas flow circulation system generates a timed pulsating gas flow and an output pressure signal having a predetermined frequency spectrum. The flow tube system has a pressure-versus-frequency damping transmission characteristic between an input from the gas flow circulation arrangement and the excitation tube, with the damping varying with a frequency of the pressure pulsations applied to the input. The continuous axial gas laser is stabilized by shifting the predetermined frequency spectrum of the pulsating gas flow generated by the gas circulation arrangement with respect to frequency and the damping transmission characteristic to minimize the pressure pulsations to the excitation tube from the gas flow circulation arrangement.

Abstract: A gas laser 10 has a gas-field enclosure 12 in which electrodes 14, 16 are operable to excite the gas within the enclosure to emit laser radiation. The region 20 between the electrodes 14, 16 contains a plasma which emits the laser radiation. At one end of the enclosure 12, there is a plasma-free region 22 undivided from the region 20. A microphone 24 is located in the plasma-free region 22. This detects pressure waves occurring in the plasma-free region when laser radiation is absorbed. The signal from the microphone is used to control a feedback circuit 26 to stabilize the frequency of the emitted laser radiation.

Abstract: There is disclosed herein several gas resupply valves for replenishment of lost gas in gas lasers in general and argon ion lasers in particular. The first embodiment uses a valve which controls flow of gas into a metering volume. The metering volume has an aperture therein which is microscopically small and which has a diffusion constant for gas moving through the aperture which is less than the time the valve is held open. The second embodiment uses the same general structure, but separates the soft sealing member of the valve from the solenoid core which moves to open and close the valve. The soft sealing member is attached to the valve body and supported above a valve seat surrounding the opening of the metering volume. The third embodiment uses a thin diaphragm which overlies a flat surface of the valve body in which are formed an input port and an output port. A solenoid applies pressure against the diaphragm to cause it to flatten against the flat surface thereby sealing the valve.

Abstract: A method of exchanging rare-isotope oxygen for common-isotope oxygen in the top several layers of an oxide-containing catalyst is disclosed. A sample of an oxide-containing catalyst is exposed to a flowing stream of reducing gas in an inert carrier gas at a temperature suitable for the removal of the reactive common-isotope oxygen atoms from the surface layer or layers of the catalyst without damaging the catalyst structure. The reduction temperature must be higher than any at which the catalyst will subsequently operate. Sufficient reducing gas is used to allow removal of all of the reactive common-isotope oxygen atoms in the top several layers of the catalyst. The catalyst is then reoxidized with the desired rare-isotope oxygen in sufficient quantity to replace all of the common-isotope oxygen that was removed.

Abstract: A honeycomb structure is coated with a catalyst to promote reassociation of CO and O.sub.2 gases to form CO.sub.2. The structure is positioned near the outlet of an optical resonator of a flowing gas CO.sub.2 laser. It is preferably positioned within a gas feedback flow system. Utilization of a honeycomb structure minimizes interference of the gas flow within the laser assembly and reduces the introduction of contaminants.

Abstract: An optical assembly isolator and laser system incorporating the same. The isolator attaches to an end of the laser system along the optical axis of the laser system. The isolator includes a flow loop wall, an optical assembly wall, an outer wall connecting the foregoing two walls, and at least one baffle wall included in the volume defined by the outer wall. The flow loop wall and the baffle wall include open first and second apertures, and the optical assembly wall supports an optical assembly. When the isolator is in place on the laser system, the first and second apertures and the optical assembly all align with the optical axis of the laser system. The edges of the first aperture and the flow loop wall can be slanted and oriented with respect to the primary flow through the laser system to induce a small circulation and redirect any entering shock waves and entrained contaminated gas toward the outer wall.

Abstract: A method for the reactivation of a tin oxide-containing catalyst of a CO.sub.2 laser is provided. First, the catalyst is pretreated by a standard procedure. When the catalyst experiences diminished activity during usage, the heated zone surrounding the catalyst is raised to a temperature which is the operating temperature of the laser and 400.degree. C. for approximately one hour. The catalyst is exposed to the same laser gas mixture during this period. The temperature of the heated zone is then lowered to the operating temperature of the CO.sub.2 laser.

Abstract: A laser generator with a catalyst for the laser gas is provided comprising a cavity which communicates with a housing receiving a catalytic cartridge, which communicates also with a laser gas reserve, and which is subjected to the action of the heat released by the laser effect. The cartridge contains, inside a mechanical filter, granules of zeolite on which a manganese dioxide catalyst has been fixed. The generator, whose output power is stabilized, has a long lifespan.

Abstract: A device for the preparation of a gas mixture includes a closed circuit. Mixture components of a gas mixture are fed with greatly differing partial pressures ranging from low to highest partial pressures to the closed circuit. The gas mixture is circulated in the closed circuit. At least one of the mixture components with low partial pressure is replenished at increasingly shorter intervals. The gas mixture is completely exchanged when a given minimal length of the intervals is reached. At least one branch parallel to a section of the closed circuit conducts the gas mixture substantially completely free of flow losses.

Abstract: A rare gas halide laser has a hollow discharge tube disposed between two metal electrodes, and a high frequency electrical generator attached to the electrodes. In order to increase the duty factor of the laser, the bore in the discharge tube is formed with two opposing walls which are separated by a small distance, preferably less than 0.5 millimeters, so that the rate of recombination of the halide compound is increased.

Abstract: A gas laser generator comprises a frame, a gas channel through which a gas flows, a mirror for obtaining a laser beam, defining a resonant cavity, an anode electrode and at least two first and at least two second cathode electrodes arranged in the lower and the upper portions of the resonant cavity, respectively, and a power source, in which a first voltage of a first electric field between the first cathode electrodes connected to the power source through a first ballast resistance and the anode electrode and a second voltage of a second electric field between the second cathode electrodes connected to the power source through a second ballast resistance and the anode electrode are so determined that the former is smaller than the latter so that the current flowing in the first electric field may be substantially equal to the current flowing in the second electric field during the electric discharges between the electrodes.

Abstract: The premixed cold reaction CW chemical laser places the secondary injectors which input fuel and/or diluent in the exit walls of the primary nozzle. These injectors are acutely angled thereto and are arranged in rows and are further grouped therein where a first injector inputs a pure diluent, a second group of injectors inputs independently of a third group.

Abstract: A gas laser such as an argon or krypton laser has an annular gas reservoir surrounding a laser bore. A series of heat-dissipating fins are connected to the laser bore and extend between the exterior of the laser bore and the interior of the coaxial gas reservoir, arranged so as to allow air to pass over the fins as it travels lengthwise in the annular space between the bore and the gas reservoir. The gas reservoir, which communicates directly with the interior of the bore via one or more tubes, can be supported in position by the fins. The gas reservoir supplies additional makeup gas for the laser bore, as the gas in the bore is slowly consumed over the life of the laser, thereby prolonging the life of the laser without gas recharge. In addition to its storage function, the coaxial annular reservoir also serves to duct cooling air, drawn by a blower, directly over the exterior of the bore and over the cooling fins, greatly improving the cooling efficiency of the laser.

Abstract: A gas laser oscillator having a gas flow smoothing device, preferably made of a cylindrical mesh, installed in the gas inlet of the electrical discharge region of the oscillator.

Abstract: A device and process using Ag.sub.2 O.sub.2 and Ag.sub.2 O.sub.3 as a catalyst for oxidizing carbon monoxide to form CO.sub.2 at temperatures between 20.degree. C. and 120.degree. C. This has particular application to CO.sub.2 lasers. In one CO.sub.2 laser embodiment, silver is distributed on the walls of the discharge volume. The silver is divided to form electrically isolated islands to prevent interference with the discharge. After an activation process, energetic forms of oxygen, such as atomic oxygen, reacts with the silver to form endothermic silver oxides which can be easily reduced by CO. In another embodiment, the Ag.sub.2 O.sub.2 or Ag.sub.2 O.sub.3 catalyst is used in a convective flow laser.

Abstract: A device and process using a gold as a catalyst for oxidizing carbon monoxide to form CO.sub.2 at ambient temperatures. This has particular application to CO.sub.2 lasers. In one CO.sub.2 laser embodiment, gold is distributed on the walls of the discharge volume. The gold is divided to form electrically isolated islands to prevent interference with the discharge. Energetic forms of oxygen, such as atomic oxygen reacts with CO on the gold catalyst. In another embodiment, the gold catalyst is used in a convective flow laser.

Abstract: For the excitation of a discharge in a laser gas, an electrode arrangement is provided which consists of at least two elongated electrodes wound approximately in a cylindrical helical line. The double helix thus formed is arranged on or concentrically within a gas flow tube.

Abstract: A piezoelectric fan is comprised of two counter-oscillating flexible blades that are driven at resonance by a bimorph comprised of two piezoceramic bending elements. The fan is provided within the flow duct of a circulating gas laser. The operation of the piezoelectric fan serves to create a flow of a laser gas medium in a desired direction through the flow duct, thereby replenishing the gas medium between a pair of laser electrodes. The fan has no wearing elements, such as bearings, and requires no bearing lubricant resulting in the elimination of lubricant hydrocarbon and bearing particulate contamination of the laser gas medium.

Abstract: In the present invention, a getter assembly is formed by a housing containing a cavity in which the passageway into the cavity is covered by an end cover which is permeable to selected gases. Internal to the cavity formed by the housing is an activated getter material for eliminating selected gas contaminants within the cavity.

Abstract: A laser gas used in a rare gas halide excimer laser is efficiently refined with little loss of the essential rare gas such as Kr, Ar or Xe by contact of the laser gas with a solid alkaline compound, e.g. Ca(OH).sub.2, for conversion of acidic impurities and also the halogen source gas such as F.sub.2 or HCl into solid metal halides and contact of the remaining gas with zeolite which is adsorbent of the remaining impurities. When the halogen source gas comprises a highly oxidizing fluorine matter the laser gas is first brought into contact with a reactive metal, e.g. Si or Fe, to convert the oxidizing fluorine matter into metal fluorides to thereby prevent formation of O.sub.2, which is obstructive to the laser operation, by reaction of the oxidizing matter with the alkaline compound.

Abstract: A temperature controller unit for use in a gas laser resonator structure using a gas lasing medium excited within a resonator cavity having reflective optical surfaces for producing a beam of coherent radiation, and the gas lasing medium being circulated through a heat exchanger to maintain a predetermined lasing temperature range. The temperature controller unit includes a tubular member of substantial length forming a primary chamber for conducting said gas lasing medium through the heat exchanger in a non-contaminating environment to reduce gas contaminate buildup on the optical surfaces in the resonator cavity, end caps sealably closing the ends of the tubular member and receiving gas lasing medium from the resonator structure, and an outlet tube having an open end positioned within the primary chamber for conveying the gas lasing medium for recirculation to the resonator structure.

Abstract: For an excimer laser system utilizing in a laser chamber a lasing material and a mixture of a diluent rare gas and a heavy rare gas and halogen rare gas in given percentages, there is disclosed a method and apparatus for reducing the expenditure of the rare gases by continuously evacuating the laser mixture from the laser chamber removing from the evacuated laser mixture any gaseous impurities to provide a cleaned laser mixture and thereafter feeding the cleaned laser mixture back into the laser chamber. Along with the cleaned laser mixture there is fed in a supplemental halogen gas. The gaseous impurities along with the halogen are removed by passing the gas through an elongated tube having calcium particles therein with a void fraction for a given length of tube in the range 0.30 to 0.60. Some of the ratio is obtained by providing alternate layers of calcium particles and inert, refractory spacers, such as stainless steel wool.

Abstract: The present invention relates to excimer laser equipment which is one kind of gas laser, and in particular to a rare gas-halide excimer laser using rare gases and halogens as laser media, and adapted to control the concentration of halogens contained in laser media therewithin on the basis of the result of the measurement of the concentration of halogens in the laser media which is being used for the oscillation of laser rays therein, whereby the stabilized oscillation of the laser is always possible.

Abstract: In order of maintaining at the more constant level the CO.sub.2 content in the gaseous mixture discharge of a transversely excited atmospheric pressure laser, a polymer product is included in advance of the laser operation in the laser chamber or within the closed fluidtight circuit where the gaseous mixture is recycled. Such polymer is produced by irradiating tripropylamine with ultraviolet photons and/or with energy electrons in the form of a layer whereby at least a portion of a solid support is coated.

Abstract: A gas laser is provided with elongated electrodes having apertures therein. he electrodes provide a transmission line for an HF electromagnetic pump which ionizes the gas, and the apertures are distributed and offset to provide passageways for efficient interaction between the hot ionized gas and a replenishing supply of cooled gas.

Abstract: A fast axial flow folded laser includes a vessel which houses heat exchangers and a pump which imparts the pumping action throughout the laser. Only one housing is necessary and this housing can also be used as an optical bench for the resonator. In one embodiment a positive displacement rotary pump is utilized and a retroreflector included to mount three fold mirrors. In the folded configuration the retroreflector provides angular stability in any two orthogonal planes parallel to the laser beam.

Abstract: A temperature responsive, gas entrapping material contained in a chamber connected to a gas laser tube selectively entraps gas to regulate the pressure in the laser tube. A temperature regulator adjusts the temperature of the gas entrapping material and thereby controls the pressure of the gas in the laser tube. The temperature of the gas entrapping material can be adjusted by cooling or by heating. The pressure in the laser tube is monitored. The tube voltage can be used to monitor the pressure. Temperature adjustment of the gas entrapping material permits development of optimum gas pressure in the laser tube for different wave lengths. In one embodiment the laser is a krypton gas laser and the gas entrapping material is activated charcoal or alumino-silicate. The gas entrapping material may be heated, during assembly of the gas laser, to a temperature high enough to remove foreign material which might otherwise interfere with the operation of the laser tube.

Abstract: A plasma tube for a gas laser includes a series of heat webs and insulative spacers between the heat webs, with tungsten bore insert members supported by the heat webs and having aligned apertures defining a laser discharge path. To produce the plasma tube, the heat webs, spacers and other connected components are assembled in a vertical stack outside the ceramic tube of the laser, with a stacking gauge which helps assure that the heat webs are correctly spaced apart within close tolerances. The heat webs lie adjacent to annular metallized areas on the inside surface of the ceramic tube when the assembly is inserted into the tube, which is precision-formed ceramic tubing. The tube assembly is heated in vertical orientation to expand the heat webs diametrically so that they engage outwardly against and are brazed to the metallized areas of the ceramic tube.

Abstract: A method of reducing an expenditure of a rare gas in an excimer laser system includes evacuating a lasing material including a mixture of diluent rare gas and removing therefrom halogen compounds. Supplemental lasing material is then added to the lasing mixture.

Abstract: A method and apparatus for reducing gas pressure in a laser wherein a miniature cryogenic pump is constructed to comprise an integral part of a laser plasma tube. The pump includes a container which holds molecular sieve material, a conduit which permits communication between the container and the plasma tube, and a valve which controls the communication along the conduit. All connections between the container, conduit, valve and plasma tube are gas-tight so as to maintain the ion integrity of the plasma tube with respect to the atmosphere. In operation, a service engineer immerses the container in a refrigerant, such as liquid nitrogen, and opens the valve until the pressure in the plasma tube reaches the desired level. Thereafter the valve is closed and the container permitted to return to ambient temperature. Further in accordance with the present invention, means are provided for preventing over pressure in the container.

Abstract: For an excimer laser system utilizing in a laser chamber a lasing material and a mixture of a diluent rare gas and a heavy rare gas and halogen rare gas in given percentages there is disclosed a method and apparatus for reducing the expenditure of the rare gases by continuously evacuating the laser mixture from the laser chamber removing from the evacuated laser mixture any foreign halogen compounds to provide a cleaned laser mixture and thereafter feeding the cleaned lasing mixture back into the laser chamber. Along with the cleaned laser mixture there is fed in a supplementing lasing material which is a mixture of the halogen gas, the diluent gas and the heavy rare gas. The percentage of the halogen gas in the supplemental material is substantially greater than the given percentage in the lasing chamber while the percentages of the diluent gas and the heavy rare gas are substantially the same as the percentage ratios of the given percentages.

Abstract: Disclosed is a method of maintaining the power of the output of a xenon chloride laser. The gases in the lasing chamber are circulated between the lasing chamber and a reforming chamber. In the reforming chamber, the gases are contacted with at least one metal chloride which is chemically less stable than hydrogen chloride. The temperature of the metal chloride in the reforming chamber is maintained between the condensation temperature of hydrogen chloride and the dissociation temperature of the metal chloride used. Also disclosed is apparatus for performing this method.

Abstract: An improved gas laser is disclosed. The laser has a support tube to support and to maintain the alignment of the optical resonator structure. The gas lasing medium is used within the support tube to maintain the tube at a substantially constant temperature above the ambient. Furthermore, an active temperature controller is disclosed. The temperature controller maintains the gas lasing medium in the support tube at a substantially constant temperature. An active pressure controller is also disclosed. The active pressure controller uses a pressure sensor, an electronic processor, and a motor-driven needle valve to maintain the pressure of the gas lasing medium in the laser within the desired operating pressure range. The laser can also be switched in operation from a continuous mode to a pulsing mode. An active power control system is disclosed wherein the power output of the laser, through an active feedback loop is maintained at the desired level.

Abstract: In electrically pumped CO.sub.2 gas lasers, there take place widely different chemical and physical processes which lead, at least partially, to undesirable interactions of the gases among themselves, and/or of the gases with the electrical and/or the optical field and/or with the materials used in the gas-filled chambers. Bodies that are equipped with surface area-enlarging structures are included in the discharge or resonator chamber or in adjacent secondary chambers. The secondary chambers by themselves act as reservoirs or as carriers of reservoirs for suitable catalysts and gas components and/or the heating of the catalysts, and have a predetermined influence over the conditions of volume and/or pressure and/or temperature. The inclusion of such secondary chambers and such structures which enlarge surface area inside the chambers make possible the attainment of at least an approximate state of equilibrium, which leads to uniformly good discharge and long life with high laser efficiency.

Abstract: Gas laser apparatus comprises a cavity 10 containing a gaseous active medium, and discharge electrodes 11 and 12 between which a potential difference may be applied to produce an electric pumping discharge in the active medium. A reservoir 17 communicates with the cavity to form a sealed enclosure containing the active medium and volume control means 19 are contained in the reservoir 17 to vary the pressure of the gaseous active medium in the cavity.

Abstract: In a laser using an electrical discharge produced between a pair of electrodes a catalyst is used for the recombination of gain medium components dissociated by the discharge. The catalyst material is confined by a catalyst container made of conductive material. The container has apertures smaller than the smallest catalyst particle and bigger than the molecule size of the gain medium. The conductive surface forms a cage which protects the catalyst, usually a powder, from the dispersing effects of the large electric fields present in the laser, and the aperture size allows the gain medium to contact the catalyst while preventing the catalyst powder from dispersing throughout the laser. The cage is placed adjacent the region in which the discharge takes place. Preferably, the cage is placed in contact with one of the electrodes in order to transfer heat from the electrode to the catalyst.

Abstract: Gas flow laser, in particular a laser through which the gas flows transversely, or through which it flow rapidly in an axial direction, which possesses a main gas circuit embracing the resonator and a circulating pump, together with an auxiliary circuit for continuously bleeding-off, conditioning and reintroducing a partial stream of the gas. The cost of the auxiliary circuit is reduced by connecting it to the main circuit upstream and downstream of the circulating pump, so that the full delivery head by the circulating pump is available for operating the auxiliary circuit. The supply of fresh gas can be introduced independently of the auxiliary circuit.