HO1S 3/22

 

The invention falls into field of laser equipment, to be exact, to multitubular gas lasers.

The known multitubular gas lasers include box-shaped or cylindrical housing with edge flanges, gas-discharge tubes, arranged inside a housing along its axis and inserted into holes in housing edge flanges, cooling system with refrigerating fluid pumping through a space between housing interior walls and exterior walls of gas-discharge tubes, two covers, hermetically connected to housing flanges from the side of tubes edges, power suppl

y and electrode system for high voltage delivery to gas-discharge tubes and for glow discharge excitation in tubes, unit of radiation outlet, anchored on the one of covers, optical resonator, optical devices of which represent back opaque mirror in the beginning of laser radiation passing, forward lead-out system, and also corner reflecting prisms, arranged near edges of each pair of gas-discharge tubes and provided the rotation of coming out of each tube laser radiation on 180⁰ and systematic passing around of laser radiation through all tubes from back opaque mirror up to radiation outlet unit [1,2]. The disadvantage of these lasers is, that at a great quantity of tubes a system of mirror alignment becomes substantially complicated.

Also is known the multitubular gas laser, including all above-mentioned devices and gas-discharge tubes are arranged in a package, in one range, equally spaced, and resonator optical devices are disposed inside covers and represent a back opaque mirror in the beginning of laser radiation passing, set in parallel to axes of gas-discharge tubes, forward lead-out system, and also two corner reflecting prisms, set near both edge surfaces of gas- discharge tubes package and completely overlapping their edges. While planes of bisectors of mirrors intersection angles in corner reflecting prisms are perpendicular to a plane of gas- discharge tubes package. They are made coincident with planes of symmetry of gas- discharge tubes arrangement over housing section and in parallel displacement relatively one another on a distance, equal half of a distance between gas-discharge tubes. That ensures rotation on 180⁰ and its input in subsequent symmetrically arranged tube and systematic passing around of laser radiation through all tubes from back opaque mirror up to radiation outlet unit [3]. In this laser at enough great quantity of gas-discharge tubes in a package is simplified the construction of rotary and adjusting units, as corner rotary prisms are common for all tubes.

This laser is most similar engineering solution to our object, i.e. the prototype.

The disadvantage of the prototype is the bulk of the construction at great quantity of gas-discharge tubes in a package, this is necessary for power multiplication. Another disadvantage - power decreasing of radiation because of losses by radiation transmission from tubes to tubes, which are taking place on considerable distance from each other.

Problems of the offered invention are power multiplication of laser radiation and increase of construction compactness. The indicated problems in our multitubular gas laser are executed because of, that gas-discharge tubes with length L are arranged equally spaced from each other in two flat packages, the planes of packages are arranged in parallel to one another

at a distance h. And tubes in one package are arranged angular q = A/L to tubes in the other package in such a manner, that tubes edges in different packages are arranged opposite one another with small displacement d . The radiation between tube edges, which are in different planes, is transmitted with the help of two two-mirror reflectors in such a manner, that ensures systematic transmission of laser radiation through all tubes, starting from a tube, which is taking place opposite of back opaque mirror, and ending on a tube, which is taking place near transparent lead-out mirror.

According to the offered invention, gas-discharge tubes inside a housing can be retained with the help of separators, having holes for refrigerating fluid passing, and simultaneously executing a role of current leads to ring electrode systems on tubes surface. Separators and edge flanges can be anchored on rods from the material with small linear expansion coefficient.

The arrangement of gas-discharge tubes equally spaced in two flat packages at tubes displacement in different packages relatively one another on a corner q = A / L, allows reducing maximal distance of laser radiation transmission outside of tubes. The diminution of path length outside of tubes gives the lowering of power losses, as at major path length outside of tubes the part of laser beam can not fall in tubes because of radiation divergence.

The support of gas-discharge tubes inside a housing by separators, anchored together with edge flanges on rods from the material with small linear expansion coefficient, allows reducing relative displacement of tubes because of heating and lowering losses of radiation by it transmission from one tube in other.

The availability of holes in separators allows increasing an efficiency of gas-discharge tubes cooling.

The lowering of power losses at laser radiation transmission from one tube in other, the lowering of losses on mirrors, the increase of cooling efficiency of gas-discharge tubes give in increase of laser output power.

The construction of the offered laser is illustrated by drawings, where on fig. 1 laser side view is shown, and on fig. 2 - laser top view. On fig. 1 laser side view of the is shown with removed front wall of a housing at section B - B. The laser consists of box-type housing 1, two edge flanges 2 are attached to a housing 1. The gas-discharge tubes 3, which ends come out on outer sides of flanges, are equally spaced from each other and inserted into holes of flanges 2.

The walls of gas-discharge tubes 3 are connected hermetically with flanges 2, and the ends of tubes 3 are closed by two covers 4 and 5, hermetically connected to the ends of flanges 2. The pumping system 6, providing the delivery of mixed gas in gas-discharge tubes 3, is connected to the covers 4,5. Through the space between interior walls of the housing 1 and exterior walls of gas-discharge tubes 3 with the help of cooling system 7 the cooling fluid is pumped.

The gas-discharge tubes 3 are retained inside the housing 1 with the help of separators 8, which simultaneously execute role of current leads from the power supply 9 to ring electrodes 10 on the surface of tubes 3. The separators 8 have holes 11 for cooling fluid passage. The separators 8 and also flanges 2 are anchored on rods 12, manufactured from a material with a small linear expansion coefficient, for example, invar.

Near an end of gas-discharge tube 3, which is taking place in the beginning of laser radiation passage, inside the cover 4 is attached the back opaque mirror 13, arranged perpendicularly to the tube axes. Besides, inside the cover 4 is attached the corner reflecting prism 14, the mirrors of which are arranged at an angle 45⁰ to an axis of gas-discharge tubes and at an angle 90⁰ to each other.

Near an end of gas-discharge tube, which is taking place at the end of laser radiation passage, inside the cover 5 is attached the front lead-out system 15. Besides, inside the cover 5 is attached also the corner reflecting prism 16, the mirrors of which are arranged at an angle 45⁰ to an axis of gas-discharge tubes and at an angle 90⁰ to each other.

The corner reflecting prisms 14 and 16 overlap the ends of gas-discharge tubes 3.

The offered multitubular gas laser operates as follows. With the help of pumping system 6 from the gas contour, formed by the volume between covers 4,5 and flanges 2, and also by the inside chamber of gas-discharge tubes 3, the air is evacuated. And then the mixed gas, representing in particular nitrogen, helium and carbon dioxide (fig. 1), is filled with. With the help of pumping system 6 the mixed gas moves with the velocity up to 1 m/s along gas-discharge tubes 3. The high voltage, igniting a glow discharge for mixed gas excitation, is brought from the power supply 9 through separators 8 to the ring electrodes 10 on tubes surface 3. The cooling of mixed gas, heating as a result of its excitation, is carried out at the expense of heat removal through walls of tubes 3. For this through space between interior walls of the housing 1 and exterior walls of tubes 3 is pumped with the help of the cooling system 7 the cooling fluid. For the temperature leveling of cooling fluid and for the fluid overflowing along the tubes in separators 8 are available holes 11. The separators 8 and also flanges 2 are anchored on rods 12, refrigerating also at fluid flowing. The rods 12 with flanges 2 execute a role of skeleton for retention of gas-discharge tubes 3 and also simultaneously form an optical bench of the resonator.

The laser radiation is shaped during a multiple reflection from back opaque mirror 13, front lead-out system 15 and corner reflecting prisms 14 and 16. It ensures systematic transmission of laser radiation through all tubes, starting from a tube, which is taking place opposite of back opaque mirror 13, and ending a tube, which is taking place near transparent lead-out mirror (fig. 2). The laser radiation, passes through the front lead-out system 15 of optical resonator, leaves out through radiation outlet unit 17.

What is claimed is:

1. A multitubular gas laser, comprising a housing with edge flanges, gas-discharge tubes, arranged inside a housing along its axis and inserted into holes of housing edge flanges, cooling system with refrigerating fluid pumping through a space between interior walls of a housing and exterior walls of gas-discharge tubes, two covers, hermetically connected to housing flanges from the side of tubes ends, power supply and electrode system for delivery of high voltage to gas-discharge tubes and excitation of glow discharge in tubes, a radiation outlet unit, anchored on one of covers, an optical resonator, optical devices, which are disposed inside covers and represent a back opaque mirror in the beginning of laser radiation passage, a front lead-out system, two corner reflecting prisms, set near both edge surfaces of gas-discharge tubes and overlapping their ends, that ensures rotational displacement of a direction of laser radiation, coming out from each tube, on an angle 180⁰ and its input in a subsequent tube and systematic bypass of laser radiation through all tubes from a back opaque mirror up to a unit of radiation outlet, characterized in, that gas-discharge tubes with length L are arranged in two flat packages, equally spaced on distance A from each other, and packages planes are arranged in parallel, while the tubes in one package are arranged at the angle q = A / L concerning the tubes of other package in such a manner, that the ends of tubes in different packages are arranged opposite one another with small displacement, and the corner reflecting prisms oriented in such a manner, that their bisectors lie between planes of tubes packages, and their mirrors transmit a radiation from tubes ends of one package to tubes ends of other package, that ensures systematic transmission of laser radiation through all tubes, starting from a tube, which is taking place opposite of a back opaque mirror, and ending in a tube, which is taking place near a lead-out transparent mirror.
2. The laser according to claim 1, wherein gas-discharge tubes inside the housing are retained by separators, having holes for refrigerating fluid passing and simultaneously executing the role of current supply to ring electrode systems on tubes surface, the separators and edge flanges are anchored on the rods from the material with small linear expansion coefficient.

 

1. Abilsiitov G.A. High-power gas-discharge CO₂-lasers and their application in technology / Moscow, “Nauka”, 1984, p.106.(in russian)
2. The handbook “Technological lasers” In 2 volumes. Volume 1: calculation, designing and operation / G.A.Abilsiitov, V.S.Golubev, V.G.Gontar, etc. Moscow, “Maschinostroenie”, 1991, p.432, fig. 56. (in russian).
3. Vasilcov V.V. Technological single-mode CO₂- laser, excited by the discharge of alternating current with power of radiation 500 W. /Izvestiya RAN, physical series, volume 57, N 12,1993, pages 123 and 127.