The device pumping powerful repetitively pulsed gas laser
(57) Abstract:The invention relates to the field of quantum electronics and can be used in high power industrial CO2laser pulse-periodic actions with pre-ionization of the laser medium ultraviolet (UV) radiation. The device pumping powerful repetitively pulsed gas laser includes the electrodes of the discharge-pumped pulsed power system, made by the scheme LC-oscillator in which the discharge electrodes, one of which is connected to a shared bus circuit, connected a serial circuit of the capacitor, the midpoint of which is connected to the high voltage input of the voltage source, the other electrode of the discharge of the pump through a charging resistance connected to a shared bus scheme, lower arm circuit of the capacitors connected to the main electrodes of the high-current switch, made on the thyratron and circuit supplied with a pre-ionizer UV radiation, made in the form prescribed in the zone of the gas medium, spark arrester, which creates a voltage ignition. In this device, the electrode of the discharge pump connected to the charging resistance and which is the cathode, is made of solid material is th form and in its Central part is a window in the form of a lattice, transparent to UV radiation, spark gap of the pre-ionizer is made linear mnogodetnym and is located directly under the grate of the anode, and the midpoint circuit capacitor connected to the anode of the thyratron through the primary winding entered into the scheme of the inductor-transformer, the secondary winding of which is connected to the sections mnohonasobneho spark gap. The technical result consists in increasing the average power and the duration of continuous operation of technological laser, as well as to improve the reliability and resource the work of its basic elements. 3 C.p. f-crystals, 2 Il. The invention relates to the field of quantum electronics and can be used in high power industrial CO2laser pulse-periodic actions with pre-ionization of the laser medium ultraviolet (UV) radiation. In particular, the invention is intended for use in the composition of the laser system for the separation of isotopes of carbon.For the formation of the pulse stable self-sustained volume discharge (OCR) atmospheric pressure is used pre-ionization of the gas environment by establishing minimum initial electron concentration around the active what about the pre-drift fill bit field of the electrons produced by an external source of ionization in the near-cathode region of the discharge gap.Known electrical discharge excitation system active medium CO2lasers with self-discharge and UV pre-ionization containing solid aluminum electrode is the cathode and the anode, is made of steel mesh in which to power the discharge used a two-stage Marx generator  . Pulse voltage between the auxiliary megastream electrode and the grid leads to the formation of corona discharges, passing in spark and serve as a source of pre-ionization in the main discharge.The disadvantage of this device pumping the laser medium is the complexity of operating the elements of the pulsed power systems with the use of pulsed hydrogen thyratrons, exceeding any of the parameters which leads to a drastic reduction in resource their work. In the result, the achievable power level TEA CO2laser is in the range of 0.5-1.0 kW.Known installation scheme for the formation of a stream of electrons drifting in an electric field, without pre-ionization of the working volume, in which a grounded mesh cathode is installed between the anode and the auxiliary electrode near the last, between cat>; source of electrons is the auxiliary discharge is ignited under mesh cathode, the flow of electrons is formed when applying the electric field in the auxiliary plasma discharge and under the influence of this field the electrons are ejected into the main discharge space between the cathode and the anode, where the electron flow is supported by the bias voltage U0.This scheme was applied in experiments on the formation of the SRF at the facility with an active volume HH cm in gas mixtures of CO2:N2:He, which managed to implement OCR in the above-mentioned mixture at atmospheric pressure with the addition of triethylamine. The filling of the discharge volume by the flow of electrons eliminates profiling electrodes and significantly reduce the level of operating voltages. The disadvantage of such a pumping device is the necessity of using leguminosarum additives in the form of triethylamine.A device four CO2laser, the sections of which are powered from independent sources pump, made in the form of two pulse generators voltage Arkadiev-Marx, discharged through the inductance to capacitance, connected in parallel RAZR, having a maximum cross-section penningrowsell ionization and now an ionisable UV radiation, resulting sufficient for ignition OCR concentration of photoelectrons, not only directly on the cathode surface, but far from it .This device has a very compact design of the electrodes and does not require the pump in a low-inductance capacitors, but it also applied leguminosarum supplements.The General lack of formation volume discharge [2, 3] with the aperture of more than 10 cm2other than the application leguminosarum additives, is the necessity of using multi-channel sources of UV pre-ionization, located at one of the electrodes of the discharge pump. The use of such preionization laser pulse-periodic action is technically extremely difficult.Known electric discharge laser device that can be used for pumping high-power pulsed-periodic gas laser, containing the electrodes of the discharge pump gas and a pulsed power system, made by the scheme LC-generator (Fitch-Govella), in which the electrode is of this circuit through a discharge resistance connected to the voltage source and to the electrode of the switch (spark gap), the second electrode of which is connected with the storage capacitor C1and one of the discharge electrodes, which are attached to the shared bus circuit, a parallel circuit of a capacitor C1and C2connected to the second charging resistance in the circuit is a separate circuit for the implementation of the UV pre-ionization in the form of the second spark gap, bit period which is installed on the periphery of the lateral zone of the gaseous medium between the electrodes of the discharge pump, and one of the electrodes of the spark gap is connected to a shared bus scheme, and the other is connected to the high voltage terminal of the additional capacitor C3equipped with a power circuit and ignition .The inductances in this scheme are the self-inductance of the leads. The advantage of the LC-oscillator compared to the Marx generator is that through the spark gap LC-oscillator pumped all the energy stored in storage capacitor, so that the switch is operating under simplified conditions. This allows instead of a spark gap is to use the thyratron and implement a pulse-periodic mode of operation of the laser with high pulse repetition rate. The pre-ionization in this scheme is carried out automatically before the of INSTRAW C3.Thus, the main advantage of this electric discharge device is in principle possible to reduce the requirements for a pulsed power system discharge by eliminating high-current switch of the circuit of the main discharge pump. However, to make a significant unloading of the elements of the pulse system power laser fails.The invention solves the problem of increasing the average power and the duration of continuous operation of technological laser, as well as improve the reliability and the service life of the key elements.The invention consists in the device pumping powerful imulse-periodic gas laser, containing the electrodes of the discharge-pumped pulsed power system, made by the scheme LC-oscillator in which the discharge electrodes, one of which is connected to a shared bus circuit, connected a serial circuit of the capacitor, the midpoint of which is connected to the high voltage input of the voltage source, the other electrode of the discharge of the pump through a charging resistance connected to a shared bus scheme, lower arm circuit of the capacitors connected to the main electrodes of the high-current switch is built in the area of the gas environment, spark arrester, to generate the voltage of the ignition. The electrode of the discharge pump connected to the charging resistance and which is the cathode, is made of solid material with enhanced photoemission properties, and the other electrode being the anode, has a flat rectangular shape and in its Central part is a window in the form of a lattice, transparent to UV radiation, spark gap of the pre-ionizer is made linear mnogodetnym and is located directly under the grate of the anode, and the midpoint circuit capacitor connected to the anode of the thyratron through the primary winding entered into the scheme of the inductor-transformer, the secondary winding of which is connected to the sections mnohonasobneho discharger.In the particular case of the execution of the proposed pumping device, the solid electrode - the cathode is made of copper, brass or magnesium, and the inductor-transformer made in the form of aerial cable transformer wound on a dielectric cylinder.The major advantage of the proposed scheme is that the duration and rate of rise dI/dt and the amplitude I of the current through the thyratron and the bit period defined bit different contours. It is obvious that these parameters are implemented in the circuit, dial-up the thyratron. The technical result arising from the use of the invention is to increase the average power of the pulsed-periodic CO2lasers up to 4 kW in the application produced by domestic industry hydrogen thyratrons CGI-2500/50 and duration of continuous operation of such lasers to several hours at a pulse repetition rate up to 200 Hz.The invention is illustrated in the drawing, where Fig.1 shows an example construction of a pumping device, and Fig. 2 is an electric diagram of a pulsed power system for the excitation of the discharge pump.High voltage solid electrode - cathode 1 dimensions HH mm, made of brass, has a profiled shape and located above the flat grounded rectangular electrode - anode 2 sizes h mm, made of copper, in the Central part of which is cut grooves with a width of 3 mm, a length of 50 mm and a pitch of 3 mm so that there is formed a window in the form of a lattice, transparent to UV radiation. Under the grid anode installed the pre-ionizer 3, representing a linear multi-element spark gap, a gap which protivorechat holes of the anode grid. The pre-ionizer is divided into two sections.m the path of the laser. The electrodes of the discharge pump in a low-inductance connected to a storage capacitor 6 pulsed power system using high-voltage input 7. Cross-section of the bit region (h mm) is determined by the size of the flat part of the cathode interelectrode distance has a value of 40 mm, and the accurate adjustment of the gap is adjusting screws 8 (Fig. 1). Pulsed power system (Fig. 2) is built on the principle scheme LC-generate (Fitch-Govella), in which high-current switch (thyratron) 9 excluded from the circuit of the discharge pump. The anode of thyratron 9 is connected to the middle point of a series circuit capacitor 6 through the primary winding specially designed for this system inductor-transformer 10, the secondary winding of which is connected to the sections mnohonasobneho discharger 3. The sectional construction of the pre-ionizer is used to reduce the distance between the UV-radiation sources and discharge area. Inductive charging resistance 11 connects the cathode 1 with a shared bus circuit, which is connected to the cathode of the thyratron 9 and the output of the lower arm circuit capacitor 6, the output of the upper arm of which is connected to the cathode 1. The midpoint of the circuit gain is usny cable transformer, wound on a dielectric cylinder.The device operates as follows.Between the electrodes 1 and 2 discharge chamber (Fig. 1) is required for TEM-CO2laser gas mixture. In the initial moment of time the cumulative capacitor 6 is charged from a source to a voltage U0, with the upper shoulder of the LC-oscillator pulse is charged through the inductor 11 (Fig. 2). After running thyratron 9 starts charging through the inductance of the primary winding of the inductor-transformer 10 of the lower storage capacitor 6 and a simultaneous rise of the voltage on the discharge gap. The voltage appearing on the secondary winding of the inductor-transformer 10, which is loaded on the partition of pre-ionizer 3, provides the sparkle in the gaps of the arrester and UV pre - ionization discharge period during the full duration of rise of voltage. The length of the front voltage overcharge is determined by the inductance of the primary winding of the inductor-transformer 10 and upon reaching the voltage to a certain value U1(U0<U<2U) there is a discharge of series-connected cumulative to the independent discharge in the gas mixture of the laser. The sectional construction of the pre-ionizer 3, the sections of which are connected to a separate winding of the inductor-transformer 10 also provides simultaneous activation of the sections and, therefore, synchronous operation of the UV-radiation sources.In the above example (agg. 1, 2) described the design of the bit module used in the development of the pumping system for TEA-CO2laser average power of 4 kW, which is included in the laser system for the separation of isotopes of carbon . The electrode system consists of three identical but electrically unconnected pairs of electrodes. Each pair of electrodes is supplied by a pulsed power supply system with separate pre-ionizer (multiple spark arrester). For each intermediate element of a spark gap connected to a small capacitor (100 pF) connected to the grounded electrode, thereby reducing the breakdown voltage and increase the stability of the pre-ionizer in the frequency mode. A break of the bit intervals of the pre-ionizer is 200 NS after the launch, and the current through the pre-ionizer is maintained during the whole duration of rise of voltage on the main discharge gap. Structurally, the pre-ionizer made in the form of Autonomous b is ionizator has eight bit intervals, located in increments of 24 mm as a high-current switches used commercially available hydrogen thyratrons type THE - 2500/50. The equivalent inductance of the inductor-transformer, converted to the primary winding, is estimated at 510-6GBV. Because hydrogen thyratrons are spread over time, which also may change as they age, in the device of the pumping laser system uses a system of synchronization that allows to adjust the trigger point of each thyratron. In addition, the system is used for stabilizing the intensity of the pulse thyratrons with fascinosum the regulator as a reliable work tietronix keys is possible only when the voltage of the tension and stress on the hydrogen generator at the level of 2-3%.Sources of information
1. E. P. Velikhov, and others, Pulse CO2lasers and their application to isotope separation. -M.: Nauka, 1983, S. 109-118, Fig. 3.19 K.2. Century Century Appolonov, and others, the Formation of self-sustained volume discharge in dense gases with large interelectrode distances. -Technical physics letters, volume 11, issue 20, 26.10.85, S. 1262-1267.3. Century Century Appolonov, etc., Powerful electric CO2Y. Baranov and others, Electric-discharge excimer lasers halides inert gases.- M: Energoizdat, 1988, S. 103-107 (prototype).5. A. C. Astakhov and other Laser system for the separation of isotopes of carbon. -Abstracts of the conference "Applied optics - 96". -St. Petersburg, September 1996, S. 265. 1. The device pumping powerful repetitively pulsed gas laser, containing the electrodes of the discharge pump and a pulse power system, made by the scheme LC-oscillator in which the discharge electrodes, one of which is connected to a shared bus circuit, connected a serial circuit of the capacitor, the midpoint of which is connected to the high voltage input of the voltage source, the other electrode of the discharge of the pump through a charging resistance connected to a shared bus scheme, lower arm circuit of the capacitors connected to the main electrodes of the high-current switch, made on the thyratron and circuit supplied with a pre-ionizer UV radiation, made in the form prescribed in the zone of the gas laser medium, spark arrester, which creates a voltage ignition, characterized in that the electrode discharge pump connected to the charging resistance and which is the cathode hatred, which is the anode gas discharge volume, has a flat rectangular shape and in its Central part is a window in the form of a lattice, transparent to UV radiation, spark gap of the pre-ionizer is made linear mnogodetnym and is located directly under the grate of the anode, and the midpoint circuit capacitor connected to the anode of the thyratron through the primary winding entered into the scheme of the inductor-transformer, the secondary winding of which is connected to the sections mnohonasobneho discharger.2. The pumping device under item 1, characterized in that the solid electrode discharge pump - cathode is made of copper or brass.3. The pumping device under item 1, characterized in that the solid electrode discharge pump - cathode is made of magnesium.4. The pumping device on PP. 1 to 3, characterized in that the inductor-transformer made in the form of aerial cable transformer wound on a dielectric cylinder.
FIELD: quantum electronics, spectrometry, and plasma chemistry.
SUBSTANCE: proposed method for firing sparkless discharge in solid gases includes ignition of main charge between first and second electrodes by applying high-voltage pulse minus across first electrode and its plus, across second one, gas being pre-ionized with aid of low-energy electron beam, photons, and plasma electrons produced directly within main-discharge space; low-energy electron beam is produced by means of open barrier discharge with high-voltage pulse applied between first electrode made in the form of grid disposed on insulator surface and additional electrode disposed on opposite side of insulator; main charge is fired not earlier than ignition of open barrier discharge; the latter and main discharge are ignited within one gas-filled chamber. Device implementing proposed method has first and second electrodes forming main discharge gap, and high-voltage pulsed power supply; first electrode is made in the form of grid disposed on insulator surface whose opposite side mounts additional electrode; high-voltage pulsed power supply is connected through minus terminal to first grid electrode and through plus one, to second electrode; it functions to ignite main discharge; additional high-voltage pulsed power supply for open barrier discharge is connected through plus terminal to first grid electrode and through minus one, to additional electrode; first grid electrode, second electrode, additional electrode, and insulator are mounted in same gas-filled chamber.
EFFECT: enhanced main-charge stability due to enhanced efficiency of gas pre-ionization in main discharge gap from pre-ionization source disposed within main discharge space.
4 cl, 5 dwg
FIELD: electrical engineering, physics.
SUBSTANCE: laser incorporates elongated solid main electrodes, each furnished with, at least, one UV-preionisation device. The gas flow zone is formed by gas flow dielectric guides and the main discharge electrode working surfaces. The said preionisation devices are arranged outside the gas flow zone to enlighten the gap between the main discharge through the gap between the main discharge electrodes and the flow dielectric guides.
EFFECT: laser efficient operation under the conditions of high pulse rate.
11 cl, 3 dwg
SUBSTANCE: present invention pertains to quantum electronics, particularly to electrode systems of gaseous TE-lasers. In the electrode system of TE-laser with corona preoinisation, the inner conductors of the corona preionisation devices are only connected between themselves. The outer conductors of the corona preionisation devices are connected to the main discharge electrodes.
EFFECT: provision for effective preionisation of the discharge gap, which does not require a high voltage lead through the case to the electrodes of the preionisation device.
5 cl, 2 dwg
SUBSTANCE: laser has a gas pumping loop in which there are series-arranged discharge gap formed by two extended electrodes, diffuser, heat exchanger, cross flow fan with an impeller and an extra channel. The inlet opening of the extra channel lies on the pressure side of the fan. The distance between the electrodes is between 0.05 and 0.25 times the external diametre of the impeller. The extra channel is in form of a convergent tube with an outlet hole directed towards the impeller of the fan on the suction side of the fan.
EFFECT: design of a compact TE-type gas laser with efficient laser gas pumping, stable operation and high pulse repetition rate.
4 cl, 1 dwg
SUBSTANCE: laser includes gas-filled chamber with the main discharge electrodes installed in it, charging circuit and discharging circuit. Charging circuit includes pulse voltage source and peaking capacitors. Discharging circuit includes peaking capacitors and the main discharge electrodes, at least one corona pre-ioniser in the form of dielectric tube with inner and outer electrodes. Outer electrode of pre-ioniser covers part of surface of dielectric tube and is connected to the main discharge electrode. At that, outer electrode of corona pre-ioniser is current lead of charging circuit.
EFFECT: improving efficiency of pre-ionisation and stability of operation.
FIELD: physics, optics.
SUBSTANCE: invention relates to laser engineering. The discharge system of a high-efficiency gas laser includes, arranged in the housing of the laser, extended first and second electrodes which define a discharge area in between. On the side of one of the electrodes there is a UV preioniser, which is in the form of a system for igniting a uniform creeping discharge between the extended ignitor electrode and an additional electrode, placed on the surface of a dielectric layer which covers an extended metal substrate connected to the additional electrode. The dielectric layer is in the form of a straight thin-wall dielectric tube with a longitudinal section. The ignitor electrode and the additional electrode are placed on the outer surface of the dielectric tube along the tube, and the metal substrate is placed inside the dielectric tube such that at least part of the surface of the metal substrate is superimposed with the extended part of the inner surface of the dielectric tube. The additional electrode is connected to the metal substrate through the longitudinal section of the dielectric tube.
EFFECT: increasing generation energy and average radiation power of the gas laser and simple design of the gas laser.
5 cl, 4 dwg
SUBSTANCE: invention refers to a gas molecule and atom excitation device in gas laser pumping systems. The device represents a tray in the form of an elongated parallelepiped or cylinder having an outer casing made of an insulation material. Parallel mesh electrodes - anode and cathode - are integrated into the casing along the tray walls. The space between the electrodes represents a discharge chamber for glow burning. Between each electrode mesh and the inner face of the tray, there are chambers used as a gas flow conditioner. Gas is individually supplied into each of the chambers. One of the side walls of the gas tray is slotted to release an excited gas molecule or atom flow from the discharge chamber into a resonant chamber generating a radiation flow.
EFFECT: downsizing and reducing power of the device and maintaining energy deposition.
3 cl, 2 dwg
FIELD: physics, optics.
SUBSTANCE: invention relates to laser engineering. The discharge system of an excimer laser includes a space discharge area (4) in a laser chamber (1) between first and second electrodes (2), (3), the longitudinal axes of which are parallel to each other; each preionisation unit (5) comprises a system for generating uniform complete creeping discharge on the surface of an extended dielectric plate (6), having an arched shape in the cross-section. The arched dielectric plate (6) can be in the form of a dielectric tube.
EFFECT: enabling laser energy and power increase.
21 cl, 13 dwg
FIELD: physics, optics.
SUBSTANCE: invention relates to laser engineering. The laser includes a gas-filled housing which is fitted with a ceramic discharge chamber with an extended high-voltage flange, a high-voltage electrode and a grounded electrode, both placed extended and placed in the discharge chamber, and at least one preionisation unit. Each preionisation unit comprises a system for generating creeping discharge, which includes an extended dielectric plate having an arched shape in the cross-section. In another version of the invention, the high-voltage electrode is placed on the inner side of the high-voltage flange and is partially transparent. The preionisation unit is placed on the back side of the partially transparent high-voltage electrode. The extended walls of the ceramic discharge chamber are preferably inclined towards the high-voltage electrode, and capacitors are inclined towards the high-voltage electrode.
EFFECT: high generation energy and power of the laser.
24 cl, 6 dwg
FIELD: power industry.
SUBSTANCE: invention relates to laser engineering. The gas laser discharge system contains the extended first and second laser electrodes, located in the laser housing, UF pre-ionizer located aside from one of laser electrodes and designed as the system of ignition of sliding discharge between extended igniting electrode and additional electrode located on the surface of the dielectric layer coating an extended metal substrate. The dielectric layer is designed as a part of direct thin-walled cylindrical tube enclosed between two planes of the tube cuts made along its length parallel to the axis. The igniting electrode is placed on the internal surface of the part of the dielectric tube along it and connected to the laser electrode, and the surface of the extended metal substrate is made concave and superposed with the part of external cylindrical surface of the dielectric layer.
EFFECT: possibility of increase of generation energy and simplification of the laser design.
4 cl, 4 dwg