Abstract: The hollow guide is designed as a thin ceramic hollow tube which is guided in an outer tube while leaving a hollow space between the outer tube and the ceramic hollow tube, the outer tube being provided at its proximal end with a connecting part having a gas connection and receiving a focusing optical system. The ceramic hollow tube is guided in the outer tube through at least one mounting part arranged at the proximal end and at least one mounting part at the distal end, which in each case is supported locally with respect to the inner wall of the outer tube. The mounting parts are thus arranged so that free flow cross-sections to conduct the rinsing gas remain in the region of support, these being matched with the internal inner cross-section of the ceramic hollow tube, so that gas flow flowing past the ceramic hollow tube is produced both on the outside and on the inside.

Abstract: Transmissive optics such as lenses, windows, and output couplers can be improved by positioning two transmissive optical elements to form a thin channel between them. High pressure gas flows through this channel to face cool the optics.

Abstract: A heart-synchronized vacuum-assisted pulsed laser technique generates a valve control signal in response to the ECG of a beating heart which is to be synchronized with the laser; the valve control signal is applied to a valve to open it and permit laser gas to be delivered to the gas inlet of the laser assisted by the draw from a vacuum source at the gas outlet of the laser, to produce a predetermined range of laser gas pressure in the laser; the valve control signal is ceased after the predetermined range of laser gas pressure has been reached to end the gas flow through the laser and enable the rebuilding of the vacuum in the vacuum source; and a laser firing signal is generated to fire the laser when the laser gas pressure is in the predetermined range.

Abstract: A turbo blower for a laser device, including a shaft having an impeller on one end thereof, a pair of bearings, having inside grease spaces and supporting the shaft Non-contact seal portions are provided for preventing an outflow of grease, whereby other spaces for retaining the grease are formed on either side of the bearings. Although the grease in the inside spaces of the bearings is urged to escape from the bearings by the centrifugal force of the rotation of the shaft, the grease is prevented from flowing out of the spaces on either side of the bearing by the non-contact seal portions.

Abstract: A carrying structure for the flanges and other elements of two laser beam paths has a geometric central plane zone that lies between and parallel to geometric central plane zones of the two laser beam paths so that the carrying structure includes the flanges of the first and second laser beam paths, is common to at least two laser segments, and that the first central plane zone of the first laser segment is disposed parallel to the second central plane zone of the second laser segment.

Abstract: A laser (2e), particularly a CO.sub.2 gas laser, is described which has a stimulating path supported on a common carrier (74e) and sub-divided into a plurality of partial paths. The partial paths (46) extend solely radially in relation to a common center (6e) and are connected to one another optically in pairs via deflecting mirrors (10e) and optical connecting paths (12e) between the deflecting mirrors (10e) at their radially outer ends. The laser (2e) is of very compact construction, has a high output and functions very reliably. Heat expansions of component of the resonator beam extend substantially radially of the center (6e) and do not result in maladjustment of the resonator beam.

Abstract: A laser oscillator device comprises an electric-discharge tube for producing an electric discharge in a laser gas contained in the electric-discharge tube for laser excitation, an optical resonator for effecting laser oscillation, and a gas circulating device having a gas blower and a cooling unit for forcibly cooling the laser gas. The gas blower has an impeller that is rotatable in the laser gas and bearings that are lubricated by grease. With this arrangement, contamination of the optical parts is prevented and the device can easily be maintained.

Abstract: A long pulse, fast flow laser system and method in which a laser having a gas inlet and a gas outlet and electrical discharge electrodes has its inlet connected through a valve to a source of laser gas and its outlet connected to a vacuum. A control circuit opens the valve upon a request for laser firing. The valve permits the laser gas to flow through the laser to the vacuum at high speed. A high-voltage power supply is triggered, creating an electrical discharge across the electrodes. After the end of the laser pulse, the valve is shut to cut off the flow of laser gas and the vacuum is reconstituted.

Abstract: A gas replenishment system for a gas laser utilizes a gas metering device between a gas reservoir and the gas laser tube which operates at a pressure below the gas reservoir pressure. The metering device incorporates a body of gas entrapping material. The tube pressure is detected and when low an electrically controlled valve is energized for a predetermined time which allows gas to flow from the reservoir, into the gas entrapping material and from there to the tube. If the tube pressure is not restored to its proper level, the system recycles for another equivalent period of time.

Abstract: Apparatus for controlling the composition of a laser gas or gas mixture includes a cryogenic gas-processor (2) connectible to a gas laser (1) selectively to receive gas or a gas mixture therefrom, remove impurities from the gas or gas mixture and selectively return the purified gas or gas mixture to the laser (1). A high temperature gas-purifier (3) is provided in gas flow connection with the processor (2) and with the laser (1) selectively to receive gas or a gas mixture therefrom, remove halogen and/or impurities from the gas or gas mixture and selectively return the dehalogenated or purified gas or gas mixture to the laser (1). Gas analysis means (4) is provided for receiving gas or gas mixture from the laser (1) to analyze it and produce output signals indicative of the actual composition of the laser gas or gas mixture.

Abstract: An NC laser device is provided which is a combination of a gas laser oscillator having a cooling mechanism for forcibly cooling a laser gas by a blower and a cooling unit, and a numerical control device. The NC laser device includes a gas temperature measuring device for measuring a gas temperature at an inlet of the blower, a casing temperature measuring device for measuring a temperature of a casing of the blower, and an abnormality detecting device, etc. The abnormality detecting device detects an abnormal state of the cooling mechanism, and stops the operation of the gas laser oscillator, when the inlet gas temperature or the casing temperature becomes higher than the respective reference value. Accordingly, an abnormal state of the cooling mechanism can be detected at an early stage, and thus secondary damage to the blower can be prevented.

Abstract: A laser oscillator device comprises an electric-discharge tube (1) for producing an electric discharge in a laser gas contained in the electric-discharge tube for laser excitation, an optical resonator (2, 3) for effecting laser oscillation, and a gas circulating device having a gas blower (15) and a cooling unit (8) for forcibly cooling the laser gas. The gas blower (15) has an impeller (16) rotatable in the laser gas. An electric motor for driving the turbo impeller has a stator (20) cooled by thermal contact with a water-cooled medium (25) or an air-cooled medium, and a rotor (19) cooled by contact with a gas flowing between the rotor (19) and the stator (20). The motor for driving the turbo impeller can thus sufficiently be cooled.

Abstract: A compact excimer laser, including a housing structure having a plurality of walls forming an internal laser cavity. A gas is located within the laser cavity and with the gas capable of lasing action. A pair of spaced electrodes are located within the laser cavity and form an electrical discharge area between the electrodes for stimulating gas within the discharge area to lasing action in accordance with an electrical discharge between the electrodes. One of the pair of electrodes is located along a central position within the cavity and is grounded to the housing structure. The other of the pair of electrodes is located adjacent to but spaced from one of the walls of the housing structure and with the other electrode mounted on a main insulator member.

Abstract: The invention relates to a process to electrically excite a laser gas, especially a CO.sub.2 --He--N.sub.2 mixture, which is admitted at an angle, preferably perpendicular, to the axial laser gas discharge gap, and which is ignited by means of bunched microwaves. In order to avoid the formation of wall boundary layers during the microwave excitation of a laser gas and in order to achieve a homogeneous, large-volume glow discharge, the microwaves are axially bunched into the laser gas discharge gap in the area of the laser gas inlet so that the microwaves and the ignited laser gas spread over the axial laser gas discharge gap.

Abstract: The invention concerns a gaseous flux laser device. To enable the removal into the atmosphere of the exhaust gases of an N.sub.2 -CO.sub.2 laser while maintaining a sufficiently low pressure in the zone where the stimulated light emission occurs, the carbon dioxide is injected through supersonic nozzles and an exhaust tube having a sufficient length is used. Application to the generating of powerful coherent light beams.

Abstract: A compact excimer laser, including a housing structure having a plurality of walls forming an internal laser cavity. A gas is located within the laser cavity and with the gas capable of lasing action. A pair of spaced electrodes are located within the laser cavity and form an electrical discharge area between the electrodes for stimulating gas within the discharge area to lasing action in accordance with an electrical discharge between the electrodes. One of the pair of electrodes is located along a central position within the cavity and is grounded to the housing structure. The other of the pair of electrodes is located adjacent to but spaced from one of the walls of the housing structure an with the other electrode mounted on a main insulator member.

Abstract: A gas laser has a closed gas flow channel in which a gas flows at high velocity through a discharge chamber, the gas discharge burning between at least two electrodes extending transversely of the gas flow. A cross-current blower for maintaining the gas flow has an axis of rotation which runs parallel to the optical axis and buckets are disposed substantially free-standing such that the gas stream flows twice through the bucket wheel, the delivery side of the blower being separated from the intake side at the inner wall of the gas flow channel by a baffle body extending in direction of the axis of the blower and reaching the outer edges of the buckets.

Abstract: A compact excimer laser, including a housing structure having a plurality of walls forming an internal laser cavity. A gas is located within the laser cavity and with the gas capable of lasing action. A pair of spaced electrodes are located within the laser cavity and form an electrical discharge area between the electrodes for stimulating gas within the discharge area to lasing action in accordance with an electrical discharge between the electrodes. One of the pair of electrodes is located along a central position within the cavity and is grounded to the housing structure. The other of the pair of electrodes is located adjacent to but spaced from one of the walls of the housing structure and with the other electrode mounted on a main insulator member.

Abstract: A compact excimer laser, including a housing structure having a plurality of walls forming an internal laser cavity. A gas is located within the laser cavity and with the gas capable of lasing action. A pair of spaced electrodes are located within the laser cavity and form an electrical discharge area between the electrodes for stimulating gas within the discharge area to lasing action in accordance with an electrical discharge between the electrodes. One of the pair of electrodes is located along a central position within the cavity and is grounded to the housing structure. The other of the pair of electrodes is located adjacent to but spaced from one of the walls of the housing structure and with the other electrode mounted on a main insulator member.

Abstract: A compact excimer laser, including a housing structure having a plurality of walls forming an internal laser cavity. A gas is located within the laser cavity and with the gas capable of lasing action. A pair of spaced electrodes are located within the laser cavity and form an electrical discharge area between the electrodes for stimulating gas within the discharge area to lasing action in accordance with an electrical discharge between the electrodes. One of the pair of electrodes is located along a central position within the cavity and is grounded to the housing structure. The other of the pair of electrodes is located adjacent to but spaced from one of the walls of the housing structure and with the other electrode mounted on a main insulator member. The main insulator member is formed of ceramic material and is located intermediate to the one wall of the housing and the other electrode but is spaced from the one wall of the housing to have the main insulator member floating relative the housing structure.

Abstract: A turbo blower for a laser comprises a motor which includes a shaft (17) having a distal end to which a turbo impeller (16) is mounted, a pair of bearings (22,23) for supporting the shaft (17), a rotor (19(, and a stator (20). A squeezed-film damper (36,37) is provided around each of the bearings (22,23), whereby vibration of the blower is damped. The damping coefficient of the squeezed-film dampers (36,37) are different from each other, whereby vibration at the bearing is reduced.

Abstract: A compact excimer laser, including a housing structure having a plurality of walls forming an internal laser cavity. A gas is located within the laser cavity and with the gas capable of lasing action. A pair of spaced electrodes are located within the laser cavity and form an electrical discharge area between the electrodes for stimulating gas within the discharge area to lasing action in accordance with an electrical discharge between the electrodes. One of the pair of electrodes is located along a central position within the cavity and is grounded to the housing structure. The other of the pair of electrodes is located adjacent to but spaced from one of the walls of the housing structure and with the other electrode mounted on a main insulator member.

Abstract: A compact excimer laser, including a housing structure having a plurality of walls forming an internal laser cavity. A gas is located within the laser cavity and with the gas capable of lasing action. A pair of spaced electrodes are located within the laser cavity and form an electrical discharge area between the electrodes for stimulating gas within the discharge area to lasing action in accordance with an electrical discharge between the electrodes. One of the pair of electrodes is located along a central position within the cavity and is grounded to the housing structure. The other of the pair of electrodes is located adjacent to but spaced from one of the walls of the housing structure and with the other electrode mounted on a main insulator member.

Abstract: Gas laser, particularly carbon dioxide laser, with a component-free gas dharge chamber between high voltage electrodes, with a beam of two resonator end mirrors multiply folded between facing reflectors and with openings of the outwardly sealed gas discharge chamber permitting the inflow and outflow of gas. A gas laser with the aforementioned features is so constructed for the purpose of increasing its efficiency, that there is a continuous gas flow in the gas discharge chamber and that the gas flow direction is parallel to the longitudinal axis of the component-free gas discharge chamber located between the reflectors.

Abstract: A gas laser includes a laser gas circuit having a by-pass line. The by-pass line includes a condenser for removing water vapor. During normal operation, the laser gas flows through the by-pass line as well as through the remaining portion of the laser gas circuit so that the water vapor portion in the laser gas flowing through the by-pass line is partly removed by the condenser. For the purpose of defrosting the condenser, the by-pass line is isolated from the rest of the laser gas circuit and, if required, is evacuated several times and rinsed with fresh laser gas. During normal operation, the gas laser can be operated with a substantially lower fresh gas supply than piror art circulating lasers.

Abstract: A very compact flow loop for circulating gas through a pulsed laser or other pulsed discharge device is disclosed. An apparatus, having greater resistance to flow and shock wave propagation in the upstream direction, preferentially converts energy from the pulsed discharge residue into flow energy and causes flow through the discharge region in the desired downstream direction. The large available work in the discharge residue lets the efficiency of the conversion apparatus be very low and yet still provide sufficient flow power to circulate gas for purging a conventional flow loop without using a separate input of power to drive the purge flow. Moderate conversion efficiency provides sufficient flow power to allow compact, high loss components to be used for a very compact flow loop with no external flow circulation power and no rotating components.

Abstract: A high-speed axial-flow gas laser generator has a plurality of anodes radially provided at the inlet section of the laser tube, and a ring-shaped cathode is provided on the gas discharge section side of the laser tube. On the upstream side from the anodes, viewed from the laser gas flow in the laser tube, a nozzle is provided which imparts a spiral rotary motion to the gas flow in the laser tube.

Abstract: A metallic vapor laser apparatus includes a cylindrical discharge tube (31) having an internal space (2), a heat-insulating material (6) encompassing the periphery of the discharge tube (31), and two electrodes (3a) and (3b) having a cylindrical portion coaxial with the discharge tube (31) and disposed at both ends of the discharge tube (31). The internal space (2) are filled with a gas containing the vapor of copper as a laser medium for effecting laser oscillation by the excitation of the filler gas and the discharge.

Abstract: The gas discharge space into which microwaves are fed via a waveguide forms a laser housing in the form of a waveguide having a longitudinal ridge therein, the laser housing being preferably dimensioned such that its critical wavelength .lambda..sub.k is shorter than or equal to the wavelength .lambda..sub.o of the microwave frequency. The gas laser may advantageously be a CO.sub.2 gas laser.

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: An excimer laser including a discharge chamber containing a mixture of halogen, rare gas and buffer gas uses two gas sources to replenish the halogen in the discharge chamber while maintaining the concentrations of all the gases at the optimum levels. One of the gas sources, source A, contains a mixture of the rare gas and the buffer gas in optimum concentrations. The other gas source, source B, contains both the rare gas and the buffer gas, in optimum relative concentrations, and also the halogen, in a concentration which is greater than optimum. As the laser operates and the gain of the laser decreases due to halogen depletion, gas from source B is injected into the discharge chamber to raise the halogen concentration. Gas is then released from the chamber to reduce the chamber pressure to the original level.

Abstract: Ceramic bearings and races, each coated or implanted with metal, glass, boron fibers, carbon fibers, jade or horneblende are disclosed as bearings for the fan assembly of a laser. The bearings and races may be silicon nitride implanted with gold and may be used in the laser without potentially contaminating supplemental lubricants.

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: A compact excimer laser, including a housing structure having a plurality of walls forming an internal laser cavity. A gas is located within the laser cavity and with the gas capable of lasing action. A pair of spaced electrodes are located within the laser cavity and form an electrical discharge area between the electrodes for stimulating gas within the discharge area to lasing action in accordance with an electrical discharge between the electrodes. One of the pair of electrodes is located along a central position within the cavity and is grounded to the housing structure. The other of the pair of electrodes is located adjacent to but spaced from one of the walls of the housing structure and with the other electrode mounted on a main insulator member.

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 gas laser device for effecting a laser oscillation while circulating a laser gas is disclosed, the gas laser device comprising a laser gun supply unit (5), a gas supply valve (6) provided at the outlet of the laser gas supply unit, an exhaust unit (9) for exhausting the laser gas in a discharge tube, a pressure sensor (7), a gas cylinder replacement check switch (5a), a control unit (10) and the like, wherein the control unit (10) exhausts the air after closing the gas supply valve, introduces a laser gas by opening the gas supply valve after the laser oscillator has been brought to a vacuum state, and effects a vacuum exhausting of the laser oscillator after closing the gas supply valve, whereby air in a pipe is exhausted from the oscillator when a gas cylinder is replaced to eliminate such disadvantages as a reduced laser output, and an unstable laser output, and the like.

Abstract: A gas laser with a discharge bore defined by a single-bore extruded ceramic discharge tube is disclosed. An outer tube is located over the discharge tube so as to define an annular space therebetween. Caps are located over both ends of the tubes and each cap is provide with at least one gas transport passage so the discharge bore and the annular space are in communication. The annular space is filled with electrically insulating, thermally conducting components such as washers, baffles and ceramic granules. When the laser is in operation the annular space serves as a gas return path so a uniform equilibrium pressure is maintained in the discharge bore. The components in the annular space inhibit the flow of electrical current in the space so all of the current flow is through the discharge bore so as to excite the gas therein. The components in the annular space also provide a thermally conductive path between the discharge tube and the outer tube to diffuse heat away from the discharge bore.

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 visible, or near to mid infra-red, hypersonic gasdynamic laser system incorporated in a hypersonic vehicle which provides high enthalpy ram air for thermodynamic excitation of the laser gases. The hypersonic vehicle defines therein a laser cavity, and ram air directed therethrough supports gasdynamic lasing operations at wavelengths less than 10.6 .mu. meters. An optical train collects the laser radiation from the laser cavity and directs it as a substantially collimated laser beam to an output aperture defined by an opening in the hypersonic aircraft too allow the laser beam to be directed against a target. The present invention is particularly applicable to a hypersonic vehicle powered by a supersonic combustion ramjet engine. Electrical energy is also produced on-board the vehicle, using ram air, or ram air plus fuel combustion, as the power source and an electrical turbogenerator (or another equivalent electrical generator) connected to a supersonic turbine.

Abstract: A fast axial flow gas laser apparatus comprising an at least essentially closed loop defining a flow path for a laser gas, an arrangement for exciting gas flowing in the loop of the apparatus to cause the gas to lase, and a regenerative compressor for flowing gas through the closed loop along the flow path. The compressor is capable of operating with a pressure ratio sufficient to flow the gas along at least a portion of the loop at a speed at least half the speed of sound in the gas with inlet pressures of only a small fraction of an atmosphere. The uniform discharge pressure of the compressor results in a uniform laser discharge or output. A positive pressure fluid pressure seal prevents lubricant at a bearing support for the impeller shaft of the compressor from moving to the impeller and possibly contaminating the laser gas being compressed thereby and also prevents surrounding air from contaminating the laser gas.

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: The invention is based on the knowledge that a laser can be used as a basic component and that the energy can be doubled by coupling together two basic components according to the invention and that the energy can be tripled by using three basic units, and so on. The power laser constitutes one module with corners, at least two modules that are at least substantially the same are connected to each other, and the modules are connected at corners of the modules by means of a connecting flange having an interior that is impermeable to laser beams, the connecting flange establishing a rectilinear joint between two gas pipelines of different modules.

Abstract: A CO2 power laser has beam paths in gas pipelines disposed in a rectangle with a plurality of corner flanges, and an end flange, and through flange that subdivide each gas pipeline. Partial paths of a gas supply device and partial paths of a gas drain device are situated in a star-shaped device between a turbo radial blower and the corner, end and through flanges. The star-shaped device has cavities in which the gas supply and gas drain paths extend.

Abstract: An improved drive coupling and bearing assembly for a recirculation fan in a long-life gas laser unit includes a plurality of frictionless gas bearings which allow journals supporting the recirculation fan to ride on a cushion of compressed laser gas. Mechanical power is transmitted from an external source to the recirculation fan through a magnetic coupling assembly, so that the walls of the sealed laser unit do not have to be breached. Additional structure is provided for spacing the driven magnet in the magnetic coupling assembly from the interior wall of the long-life laser unit.

Abstract: In a laser arrangement, solid or liquid material, at least part of which comprises a laser amplifying medium, is atomized in a gas prior to being applied to a discharge region. In one embodiment of the invention, the gas is combustible and is ignited to produce a flame which provides heating of the material. The invention is particularly applicable to metal vapour lasers.In another embodiment of the invention, the material is atomized in an inert gas and a discharge within a laser discharge tube is used to provide excitation.

Abstract: A CO.sub.2 gas laser is equipped with a gas mixture control arrangement which introduces into the interior of the laser, of the constituent component of water, only hydrogen, in such amounts based on the instantaneous humidity of the gas mixture that the dew point of water vapor resulting from the combination of the thus introduced hydrogen with incidental oxygen present in the laser interior as an incident to the operation of the laser is maintained within a predetermined range.

Abstract: An active gas based on CO.sub.2 penetrates under pressure into a discharge chamber (20) via injection orifices (10) formed through the upstream face of said chamber. These orifices leave considerable solid portions (22) about themselves in said face such that the gas forms jets which diverge up to an outlet grid (12) constituting a common anode. Cathodes (8) are individually powered by a block (14) and give rise to discharges which are widened on the edges of said jets by large-amplitude gas recirculation currents, thereby increasing the electrical power injected. The invention is particularly applicable to power lasers.

Abstract: A gas laser includes a laser cavity, mirror means defining an optical path in the cavity, electrodes defining an electric discharge path in the cavity, the electrodes including at least one anode member having a passage therethrough which at one end opens into the cavity, and gas supply means for injecting gas into the cavity through the passage, wherein the wall of the passage at said one end and the exterior of the anode member around the end of said passage is electrically insulated and an electrically conducting anode surface defining the root of the discharge is provided inwardly of the perimeter of the open end of the passage.

Abstract: An axial flow gas transport laser comprising an excitation tube through which gas flows along an axis of the tube, an inlet arrangement to feed gas towards the excitation tube and an outlet arrangement to discharge gas from the excitation tube. At least one of the inlet and outlet arrangements comprises a circumferential opening arrangements evenly distributed along the periphery of the excitation tube, substantially in a cross-section plane of the tube. A gas flow channel arrangement to the opening arrangement is directed at least substantially in the direction of the excitation tube axis and into the excitation tube at the opening arrangement for preventing wide-areal turbulances of the gas flowing in the excitation tube.