The invention falls into field of laser equipment, to be exact to electrodischarge multitubular lasers with diffusion refrigeration of a mixed gas.

The known electrodischarge multitubular lasers with diffusion refrigeration of a mixed gas comprise box-shaped or cylindrical housing with edge flanges; gas-discharge tubes, arranged in the form of a package inside a housing along its axis and inserted into holes in edge flanges of a housing; cooling system with refrigerating fluid pumping through space between interior walls of a housing and exterior walls of gas-discharge tubes; two covers, hermetically connected to flanges of a housing on the side of tubes edges; system of mixed gas pumping along gas-discharge tubes, through covers; power supply and electrode system for high voltage delivery to gas-discharge tubes and glow discharge excitation in tubes; radiation outlet unit, anchored on one of covers; optical resonator, the optical devices of which represent an opaque mirror in the beginning of laser radiation course, forward lead-out system, and also corner reflecting prisms, arranged near edges of each pair of gas-discharge tubes and providing rotational displacement of laser radiation, coming from each tube, at an angle 180⁰ and systematic bypass of laser radiation through all tubes from a back opaque mirror up to radiation outlet unit [ 1,2] . The disadvantage of these lasers is in, that at a great quantity of tubes a system of mirror alignment becomes substantially complicated.

Also is known the electrodischarge multitubular laser with diffusion refrigeration of a mixed gas, including all above-mentioned devices, while gas-discharge tubes in a package are arranged in one line, on equal distance from each other. And the optical devices of the resonator are disposed inside covers and represent back opaque mirror in the beginning of laser radiation course, which takes place along 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 the planes of bisectors of mirrors intersection angles in corner reflecting prisms are perpendicular to plane of gas-discharge tubes package. They are combined with planes of symmetry of gas-discharge tubes arrangement on section of the housing and displaced in parallel rather one another on distance, equal half of distance between gas-discharge tubes. This ensures rotational displacement at an angle 180⁰, and input in the subsequent, symmetrically arranged tube, and systematic bypass of laser radiation through all tubes from the back opaque mirror up to an outlet unit [ 3] . In this laser at enough quantity of gas-discharge tubes in the package is simplified the construction of rotary and adjusting units, as for all tubes corner rotary prisms are common.

This laser is most close engineering solution to the offered object, i.e. prototype.

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

Problems of the invention - power multiplication of laser radiation and pinch of construction compactness.

The indicated problems are executed because gas-discharge tubes in the package are arranged on a circle, on equal distance from each other. And the planes of bisectors of mirrors intersection angles in corner reflecting prisms are displaced rather one another around of circle center at an angle p /n, where n - number of gas-discharge tubes on a circle. It ensures systematic transmission of laser radiation through all tubes, starting from a tube, which is taking place opposite of back opaque mirror, and ending a tube, which is taking place about the opposite end of circle diameter. And the back opaque mirror is arranged near an end of gas-discharge tube, perpendicularly to its axis.

According to the invention gas-discharge tubes inside the housing can hold on by separators, having the holes for refrigerating fluid passing and simultaneously executing a role of current leads to ring electrode systems on tubes surface. The separators and edge flanges can be anchored on a rod from a material with a small linear expansion coefficient, arranged at center of a circle, formed by gas-discharge tubes.

Besides, gas-discharge tubes in the package can be arranged on one circle or on several concentric circles, in each circle there is an identical quantity of tubes and they are arranged in radial planes. And for laser radiation delivery from one circle in other are arranged near ends of output and input tubes the corner reflecting mirrors.

The offered electrodischarge multitubular laser with diffusion refrigeration of a mixed gas can differ by that near an input end of last on laser radiation course tube of the same circle, as back opaque mirror, the forward lead-out system of the optical resonator is arranged. It is fulfilled in the form of reflective – rotary unit, integrated with a corner reflecting mirror, transmitting a part of laser radiation in the subsequent circle, and another part of radiation reflecting back in the resonator.

Arrangement of gas-discharge tubes in the package on a circle, with equal distance from each other, at displacement of bisectors planes of mirrors intersection angles in corner reflecting prisms rather one another, around of circle center at an angle p / n, where n - the quantity of gas-discharge tubes on a circle, allows reducing maximal distance of laser radiation transmission outside of tubes. The arrangement of back opaque mirror near an end of gas-discharge tube, perpendicularly to tube axes also gives in diminution of laser radiation path length outside of a tube. The diminution of a path length outside of tubes gives in lowering of power losses, as at a major path length outside of tubes the part of laser beam can not get into tubes because of radiation divergence.

The support of gas-discharge tubes inside the housing by separators, anchored together with edge flanges on the rod from a material with a small linear expansion coefficient, allows reducing the displacement of tubes concerning their axial and lowering losses of radiation at its transmission from one tube in other.

The arrangement of forward lead-out system of the optical resonator near an input end of last, on laser radiation course, tube of the same circle, as back opaque mirror, allows gaining in tubes of the given circle oscillation of laser radiation. In tubes of remaining circles there will be an amplification of laser radiation. It gives in lowering of power losses at reflection from mirrors, as in a gain mode the losses on mirrors are less.

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

Lowering of power losses at laser radiation transmission from one tube in other, lowering of losses on mirrors, pinch of efficiency of refrigeration of gas-discharge tubes give in pinch of laser output power.

The arrangement of gas-discharge tubes in the package on several concentric circles also gives in pinch of radiated power, and simultaneously ensures largely the construction compactness. Besides, the construction compactness rises at using separators as current supply.

The construction of the offered laser is illustrated by the constructed drawings, where on fig. 1 the side view the laser is shown; on fig. 2 - the plan of laser radiation course, section A - A on fig. 1; on fig. 3 - section Б – Б on fig. 1. On fig. 4 is shown the laser with removed forward wall of the housing, side view, section B - B on fig. 1. The laser consists of box-shape housing 1, two edge flanges 2 are attached to the housing 1. Into holes of flanges 2, on a circle with equal distance from each other are inserted the gas-discharge tubes 3, the ends of which leave on outer sides of flanges.

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

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

Inside the cover 4, near an end of gas-discharge tube 3, taking place in the beginning of laser radiation course, is attached the back, opaque mirror 13, arranged perpendicularly 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 gas-discharge tubes axis and at an angle 90⁰ to each other.

Inside the cover 5, near an end of gas-discharge tube, which is taking place at the end of laser radiation course, is attached the forward lead-out system 15. Besides, inside the cover 5, to the flange 2 is also attached corner reflecting prism 16, which mirrors are arranged at an angle 45⁰ to gas- discharge tubes axis and at an angle 90⁰ to each other.

The corner reflecting prisms 14 and 16 overlap ends of gas-discharge tubes 3. The planes of bisectors of mirrors intersection angles in corner reflecting prisms 14 and 16 are combined with planes of symmetry of an arrangement of gas-discharge tubes on housing section. While the planes of bisectors are displaced rather one another around of circle center, formed by tubes, at an angle p / n, where n - number of gas-discharge tubes on a circle.

On fig. 4 is shown the plan of laser radiation course, section B - B, in which the gas-discharge tubes in the package are arranged on several concentric circles, in this case on three. On fig. 5 is figured the top view of the laser, section G - G on fig. 1. In each circle, in this case, is present eleven tubes, arranged in eleven radial planes. The laser radiation from tubes of an inside circle to the tubes of a mean circle is transmitted with the help of corner reflecting mirror 18, arranged near ends of input and output tubes. The laser radiation from tubes of an inside circle to tubes of an outside circle is transmitted with the help of corner reflecting mirror 19, arranged near ends of input and output tubes of these circles. On fig. 6 is figured the unit of laser radiation transmission from tubes of an inside circle to tubes of a mean circle. Where the forward lead-out system 15 of optical resonator is arranged near an output end of last tube of an inside circle, i.e. same circle, as back, opaque mirror. The forward lead-out system 15 of optical resonator is fulfilled in the form of reflective – rotary unit, integrated with corner reflecting mirror. This unit in this case consists from corner reflecting mirror 18, formed by mirrors 20 and 2. And on the mirror 20 there is a diffraction array, reflected from which the radiation of 1-st order hits back in a tube. That ensures a back coupling for the laser generator, formed by tubes of an inside circle. And the radiation, reflected in 0 - order hits in tubes) of exterior circles and compresses the energy, accumulated in active medium, in an amplifying mode.

The offered electrodischarge multitubular laser with diffusion refrigeration operates as follows. With the help of pumping system 6 from a gas contour, formed with volume between covers 4 and 5 and flanges 2 and also inside cavity of gas-discharge tubes 3, air is evacuated. And then is pumped the mixed gas, representing in particular nitrogen, helium and carbon dioxide (fig. 1). With the help of pumping system 6 the mixed gas moves with velocity up to 1 m/s along gas-discharge tubes 3, arranged on section of the housing 1 on a circle, on equal distance from each other. The high voltage, igniting a glow discharge for mixed gas excitation, is delivered from the power supply 9 to ring electrodes 10 on tubes surface through separators 8. The refrigeration of a mixed gas, heated as a result of its excitation, is carried out at the expense of heat removal through walls of tubes 3. For what through space between interior walls of the housing 1 and exterior walls of tubes 3 with the help of cooling system 7 is pumped the refrigerating fluid. For leveling of refrigerating fluid temperature and fluid overflowing along tubes in separators 8 are available holes 11. The separators 8 and also flanges 2 are anchored on the rod 12, also cooling at refrigerating fluid passing. The rod 12 with flanges 2 executes a role of skeleton for retaining of gas-discharge tubes 3, and also simultaneously forms an optical bench of the resonator.

The laser radiation is shaped during a multiple reflection from the back opaque mirror 13, forward lead-out system 15 and corner reflecting prisms 14 and 16. The planes of bisectors of mirrors intersection angles in corner reflecting prisms 14 and 16 are combined with planes of symmetry of an arrangement of gas-discharge tubes 3 on section of the housing 1. They are displaced rather one another around of a circle center, formed by tubes 3, at an angle =p /n, where n - quantity of gas-discharge tubes on a circle. This ensures systematic transmission of laser radiation through all tubes, starting from a tube, which is taking place opposite of the back opaque mirror 13, and ending a tube, which is taking place near the opposite end of a circle diameter (fig. 2-3). The laser radiation, having passed the forward lead-out system 15 of optical resonator, leaves out through the radiation outlet unit 17.

In case of an arrangement of gas-discharge tubes 3 in a package on several concentric circles the laser radiation is transmitted from the last (output) tube of one circle with the help of corner reflecting mirrors 18 and 19, arranged near ends of these tubes (figs. 4 and 5).

At an arrangement of forward lead-out system 15 near the output end of last on laser radiation course tube of the same circle, as back opaque mirror 13, the laser radiation, reflected in the 1-st order from a diffraction array, marked on the mirror 20 of corner reflecting mirror 18, is returned back in the optical resonator. The laser radiation, reflected in 0 order with the help of the mirror 21 of corner reflecting mirror 18, is transmitted in gas-discharge tubes of other circles (figs. 6). In the given variant the tubes of a circle with the back, opaque mirror 13 and forward lead-out system 15 operate in radiation oscillation mode, and the tubes of remaining circles - in radiation gain condition.

What is claimed is:

1. An electrodischarge multitubular laser with diffusion cooling of mixed gas, comprising box-shaped housing with edge flanges, gas-discharge tubes, arranged as a package inside a housing along its axis and inserted into holes in edge flanges of a housing; cooling system with pumping of refrigerating fluid through space between interior walls of a housing and exterior walls of gas-discharge tubes; two covers, hermetically connected to flanges of a housing on the side of tubes ends; system of mixed gas pumping via gas-discharge tubes, through covers; power supply and electrode system for high voltage delivery to gas-discharge tubes and glow discharge excitation in tubes; radiation outlet unit, anchored on one of covers; optical resonator, the optical devices of which are disposed inside covers and represent a back opaque mirror in the beginning of laser radiation passage, forward lead-out system, two corner reflecting prisms, set near both edge surfaces of gas-discharge tubes package and overlapping their ends, while planes of bisectors of mirrors intersection angles in corner reflecting prisms are displaced relatively each other and are matched with planes of symmetry of gas-discharge tubes arrangement along housing section, that ensures rotational displacement of laser radiation direction, coming out of each tube, at an angle 180⁰ , and its input in subsequent symmetrically arranged tube, and systematic bypass of laser radiation through all tubes from a back opaque mirror up to radiation outlet unit, characterized in, that gas-discharge tubes in a package are arranged on a circle, on equal distance from each other; and planes of bisectors of mirrors intersection angles in corner reflecting prisms are displaced relatively each other around of circle center at an angle p / n, where n - number of gas-discharge tubes on a circle, that ensures systematic transmission of laser radiation through all tubes, starting from a tube, taking place opposite of back opaque mirror, and ending with a tube, which is taking place near an opposite end of circle diameter; and back opaque mirror is arranged near an end of gas-discharge tube, perpendicularly to its axis.
2. The laser according to claim 1, wherein the gas-discharge tubes inside the housing are retained by separators, having the holes for refrigerating fluid passing and simultaneously executing the role of conductor for ring electrode systems on tubes surface; the separators and edge flanges are anchored on a rod from a material with a small linear expansion coefficient, arranged in circle center, formed by gas-discharge tubes.
3. The laser according to claims 1 and 2, wherein the gas-discharge tubes in the package are arranged on several concentric circles, in each circle there is an equal quantity of tubes and they are arranged in radial planes; and for laser radiation delivery from one circle to another, near ends of input and output tubes of the circles are arranged the corner reflecting mirrors.
4. The laser according to claims 1 – 3, wherein near the output end of last on laser radiation passage tube of the same circle, as the back opaque mirror, is arranged the forward lead-out system of the optical resonator, fulfilled in the form of reflective - rotary unit, integrated with the corner reflecting mirror, transmitting a part of laser radiation in the subsequent circle, and a part of the radiation reflecting back in the resonator.

 

 

1. Abilsiitov G.A. High-power gas-discharge CO₂-lasers and their application in technology / Moscow, “Nauka”, 1984, p.106, fig. 11(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. Vasiltcov 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 - 127.