WO1989010641A1 - Laser a gaz - Google Patents

Laser a gaz Download PDF

Info

Publication number
WO1989010641A1
WO1989010641A1 PCT/DE1989/000248 DE8900248W WO8910641A1 WO 1989010641 A1 WO1989010641 A1 WO 1989010641A1 DE 8900248 W DE8900248 W DE 8900248W WO 8910641 A1 WO8910641 A1 WO 8910641A1
Authority
WO
WIPO (PCT)
Prior art keywords
beam path
laser
laser according
reflectors
mirrors
Prior art date
Application number
PCT/DE1989/000248
Other languages
German (de)
English (en)
Inventor
Gerd Herziger
Peter Loosen
Original Assignee
Fraunhofer-Gesellschaft Zur Förderung Der Angewand
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Priority claimed from DE19883813569 external-priority patent/DE3813569A1/de
Application filed by Fraunhofer-Gesellschaft Zur Förderung Der Angewand filed Critical Fraunhofer-Gesellschaft Zur Förderung Der Angewand
Publication of WO1989010641A1 publication Critical patent/WO1989010641A1/fr

Links

Classifications

    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01S—DEVICES USING THE PROCESS OF LIGHT AMPLIFICATION BY STIMULATED EMISSION OF RADIATION [LASER] TO AMPLIFY OR GENERATE LIGHT; DEVICES USING STIMULATED EMISSION OF ELECTROMAGNETIC RADIATION IN WAVE RANGES OTHER THAN OPTICAL
    • H01S3/00—Lasers, i.e. devices using stimulated emission of electromagnetic radiation in the infrared, visible or ultraviolet wave range
    • H01S3/02—Constructional details
    • H01S3/03—Constructional details of gas laser discharge tubes
    • H01S3/038—Electrodes, e.g. special shape, configuration or composition
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01S—DEVICES USING THE PROCESS OF LIGHT AMPLIFICATION BY STIMULATED EMISSION OF RADIATION [LASER] TO AMPLIFY OR GENERATE LIGHT; DEVICES USING STIMULATED EMISSION OF ELECTROMAGNETIC RADIATION IN WAVE RANGES OTHER THAN OPTICAL
    • H01S3/00—Lasers, i.e. devices using stimulated emission of electromagnetic radiation in the infrared, visible or ultraviolet wave range
    • H01S3/05—Construction or shape of optical resonators; Accommodation of active medium therein; Shape of active medium
    • H01S3/08—Construction or shape of optical resonators or components thereof
    • H01S3/081—Construction or shape of optical resonators or components thereof comprising three or more reflectors

Definitions

  • the invention relates to a gas laser, in particular a carbon dioxide laser, with a beam path that is folded several times between two resonator mirrors, for the folding of which plane reflector surfaces are present and whose beam path sections are spatially arranged between the reflectors, according to a patent (patent application P 37 16 873.8). .
  • a plurality of reflectors folding the laser beam retroreflectively are as
  • the folding generally causes problems in the beam guidance and in the beam quality.
  • the beam guidance is adversely affected by the fact that the beam is not reflected exactly in the desired direction because the mirror adjustment is not exact or by the Ausge staltung of the laser can be influenced in an undesirable manner.
  • the beam quality is deteriorated, for example, by diffraction effects when reflecting in the corner areas of roof mirror.
  • the disadvantages increase with the number of folds.
  • the helical winding arrangement of the beam path sections leads to a very good utilization of the available space of active material. It is thus possible to increase the performance of lasers in particular that do not have circulation cooling; because these lasers generally require large volumes of active material in order to achieve sufficiently high outputs. If these volumes can now be used better, this is advantageous for a compact laser structure and the folding concept is therefore particularly suitable for utilizing reinforcing active materials in the smallest space. At the same time, the folding concept is particularly suitable for diffusion-cooled laser systems, which therefore do not have gas recirculation cooling, because the heat loss must be removed there only via the walls and the compact structure of the laser according to the invention favors such a rapid removal of the heat loss.
  • the folding according to the invention is the cause of a higher overall efficiency of the laser system.
  • a compact arrangement of the resonator basically enables a correspondingly compact structure of the laser, which contributes to its stability and in particular leads to the fact that the adjustment problems are reduced, which are otherwise not without importance in the case of longitudinally extending laser structures.
  • the simple and compact structure also offers a prerequisite for achieving a high beam quality.
  • the laser is designed such that it has at least three reflector surfaces, at least one of which folds the beam path at least twice, and that at least one reflector is arranged so as to deflect a beam path section deflecting in the winding direction.
  • the three reflector surfaces can be equidistant from each other be arranged so that the shape of a triangular prismatic body results for the space enclosed by the beam path. It is also important that at least one of the three reflector surfaces folds the beam path at least twice; because this reduces the structural effort for the reflector.
  • the adjustment is also simplified since only a single reflector surface has to be adjusted. The tilting of at least one reflector surface causes the subsequent beam path sections to occupy a different area of the active medium.
  • the other beam path sections lie in the same plane. If, on the other hand, all three reflector surfaces are arranged slightly tilted, preferably with the same tilt angle, there is a uniform helical winding of the beam path.
  • the reflectors of the laser have a total of four reflector surfaces that align the adjoining beam path sections at right angles to one another, on the one hand to achieve the longest possible beam path with the best possible use of an available volume, but on the other hand a large construction effort due to an unnecessary large number of reflectors, electrodes, etc . to avoid.
  • the electrode areas available for cooling are comparatively large in relation to the total volume of the active material, so that the heat generated can be easily removed or the power of the laser related to a unit volume is comparatively large. This is particularly the case when the reflector surfaces are arranged opposite the corners of the inner electrode in the intersection areas of the planes of the plate electrodes.
  • the above-described structure of the laser in the resonator area also has advantages for circulation cooling.
  • the laser structure is such that it has gas flows parallel to the radiation path with entries in the corner areas opposite the inner electrode and exits in the center of their flat surfaces.
  • the main advantage is with the front flow guidance described that the gas flow takes place parallel to the direction of propagation of the light. This avoids temperature and density gradients across the beam, which would have a negative impact on the beam quality.
  • the flow guidance thus enables a high jet quality with continuous and also with pulsed operation.
  • the laser structure becomes particularly compact when a gas cooler connected to a gas circulation device is installed in the inner electrode.
  • the two resonator mirrors are aligned with one another, including a beam path section, resulting in a ring resonator, which is used, for example, in dye lasers.
  • one of the resonator mirrors is, as usual, a partially transmitting mirror, which thus couples out part of the laser light, but couples another part back into the beam path via the beam path section to the second resonator mirror.
  • FIG. 4 a representation corresponding to FIG. 3 with gas circulation
  • FIGS. 5 a to c three different tubular housings of the
  • the helical arrangement of the beam path is carried out by only two beam path sections arranged spatially offset from one another.
  • the beam path 13 shown in FIG. 1 of a resonator system of the lasers 10 shown in FIGS. 3 and 4 shows a helical arrangement of the beam path sections 16 of the beam path 13.
  • the fall device of the beam path 13 is carried out with reflectors (not shown in FIG. 1) at the points 30.
  • the reflectors located there are, according to FIGS Folds the beam path 13.
  • the beam path will be designed according to FIG. 1, since then a long beam path 13 is present in a relatively small volume between the resonator mirrors 11, 12, so that the laser can accordingly have a very compact structure.
  • the reflectors required for folding at points 30 are each a plane mirror, so that the entire resonator arrangement needs four plane mirrors.
  • a similarly simple arrangement results from the use of two retroreflective roof edge mirrors as reflectors 15 according to FIG. 2.
  • multiple folding takes place such that the beam path sections 16 related to a reflector surface 14 are arranged at right angles to each other.
  • the helical arrangement of these beam path sections 16 cannot be seen in detail in the perspective illustration in FIG. 2, but is indicated by the fact that the horizontal 31 is shown. which obviously forms an angle with the longer beam path sections 16, as a result of which the tilting of one reflector 15 or both reflectors 15 is indicated.
  • This reflector tilt causes a beam path section to be deflected in the direction of the turns.
  • Fig. 2 shows that the formed as a roof mirror
  • Reflectors 15 require an essentially rectangular or guader-shaped arrangement of the beam path sections 16 because the reflector surfaces 14, which are at right angles to one another, permit only short beam path sections between them, if one disregards a disproportionately large design of the roof mirror. Such a configuration will therefore generally only be used if no electrode is installed between the beam path sections 16, ie the entire space occupied by the beam paths is filled with gas. In comparison with conventional systems, however, such a construction is also comparatively compact and has the advantage above all of using only less flat reflector surfaces with comparatively little adjustment sensitivity. As a result, such a laser can also be produced at significantly lower manufacturing costs than previously known lasers.
  • the beam path 13 extends between the resonator mirrors 11, 12 and essentially within a housing 26.
  • the mirror 11 is opaque, while the mirror 12 is partially transparent, so that an externally available laser beam 29 is coupled out.
  • the reflectors 15 adjacent to the mirrors 11, 12 are arranged in such a way that they do not obstruct the beam path 13.
  • the upper right reflector 15 is arranged above the beam path section to the mirror 11, while the lower right reflector 15 'is below of the beam path section leading to the mirror 12 is arranged.
  • Such an arrangement is readily possible with an arrangement of the mirrors 11, 12 that is offset perpendicular to the plane of representation.
  • Electrodes 18, 19 are present in the interior of the housing 26.
  • the electrode 18 is designed as a cylindrical tube and arranged within the tortuous beam path 13. It has four flat surfaces 17 facing the beam path sections 16, opposite which plate electrodes 19 are arranged on the other side of the beam path sections 16.
  • the electrode 18 may be gas tight in which case the active medium is confined to the area between the inner electrode 18 and the housing 26.
  • FIG. 3 shows in particular the compact arrangement of the laser 10 or the folded beam path 13 with respect to the cross-sectional dimensions.
  • the reflectors 15 are arranged in the sectional areas 21 of the planes of the plate electrodes 19 opposite the corners 20 of the inner electrode 18, specifically within the housing 26.
  • the housing 26 can accordingly be tubular, that is to say with a square cross section according to FIG. 5a.
  • the stability of the housing is improved by the housing 27, which has stiffening ribs 27 ′′ extending from its edges 27 ′.
  • 5c shows a housing 28 with an annular cross section with a correspondingly high mechanical rigidity.
  • FIG. 4 The structure of the laser shown in FIG. 4 corresponds essentially to that of FIG. 3.
  • gas cooling is provided, in which the cooling gas, which at the same time forms the active medium, can be fed into the housing 26 on the front side as well as through side inlet openings.
  • 4 shows entrances 23 of gas flows 22 in the corner areas opposite the inner electrode 18, that is to say opposite their corners 20 and exits 24 in the flat surfaces 17 of the inner electrode. These outlets are arranged in the center, so that gas flows 22 parallel to the beam path result in the excitation regions 32 of the active medium between the electrodes 18, 19, which has the advantage of largely avoiding temperature and density gradients occurring transversely to the beam path, so that the beam 29 has a high quality.
  • the gas is circulated using a gas circulating device, not shown, for example by means of root pumps or turbine pumps. From the area between the electrodes 18, 19, the gas flows into the interior 33 of the electrode 18, from which it is discharged at the end.
  • a gas cooler 25 is advantageously installed in the interior of the electrode 18, to which the heated gas is supplied and from which the cooled gas is returned to the inlets 23 through an outflow opening 34.
  • the coolant for the gas cooler 25, not shown in detail, is expediently supplied on one end face and discharged on the other end face, so that a high throughput rate of the coolant and thus a correspondingly large cooling effect can be achieved.
  • the method according to the invention serves to make a laser as compact as possible.

Landscapes

  • Physics & Mathematics (AREA)
  • Electromagnetism (AREA)
  • Engineering & Computer Science (AREA)
  • Plasma & Fusion (AREA)
  • Optics & Photonics (AREA)
  • Lasers (AREA)

Abstract

Un laser, notamment un laser au dioxyde de carbone, comprend un trajet de rayons à déflexions multiples qui s'étend entre deux miroirs résonateurs terminaux. Les déflexions sont assurées par des surfaces planes de réflecteurs, les sections du trajet des rayons s'étendant spatialement entre les réflecteurs. Afin d'obtenir des lasers de ce genre aussi compacts que possible, les sections du trajet des rayons sont enroulées en spirale.
PCT/DE1989/000248 1988-04-22 1989-04-21 Laser a gaz WO1989010641A1 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DEP3813569.8 1988-04-22
DE19883813569 DE3813569A1 (de) 1987-05-20 1988-04-22 Gaslaser

Publications (1)

Publication Number Publication Date
WO1989010641A1 true WO1989010641A1 (fr) 1989-11-02

Family

ID=6352633

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/DE1989/000248 WO1989010641A1 (fr) 1988-04-22 1989-04-21 Laser a gaz

Country Status (1)

Country Link
WO (1) WO1989010641A1 (fr)

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO1998006156A1 (fr) * 1996-08-07 1998-02-12 Lumonics Inc. Laser a faisceau replie et a elements multiples
US5867518A (en) * 1996-08-07 1999-02-02 Lumonics Inc. Multiple element laser pumping chamber
US5867519A (en) * 1996-08-07 1999-02-02 Lumonics Inc. Multiple element, folded beam laser

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR1356934A (fr) * 1961-09-14 1964-04-03 Siemens Ag Amplificateur optique
US4740983A (en) * 1987-08-28 1988-04-26 General Electric Company Laser apparatus for minimizing wavefront distortion
EP0292277A1 (fr) * 1987-05-22 1988-11-23 Rimon Financing, Inc. Systèmes à laser à plis multiples
WO1988009578A1 (fr) * 1987-05-20 1988-12-01 Fraunhofer-Gesellschaft Zur Förderung Der Angewand Laser a gaz

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR1356934A (fr) * 1961-09-14 1964-04-03 Siemens Ag Amplificateur optique
WO1988009578A1 (fr) * 1987-05-20 1988-12-01 Fraunhofer-Gesellschaft Zur Förderung Der Angewand Laser a gaz
EP0292277A1 (fr) * 1987-05-22 1988-11-23 Rimon Financing, Inc. Systèmes à laser à plis multiples
US4740983A (en) * 1987-08-28 1988-04-26 General Electric Company Laser apparatus for minimizing wavefront distortion

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO1998006156A1 (fr) * 1996-08-07 1998-02-12 Lumonics Inc. Laser a faisceau replie et a elements multiples
US5867518A (en) * 1996-08-07 1999-02-02 Lumonics Inc. Multiple element laser pumping chamber
US5867519A (en) * 1996-08-07 1999-02-02 Lumonics Inc. Multiple element, folded beam laser
EP0986150A1 (fr) * 1996-08-07 2000-03-15 Lumonics Inc. Laser à faisceau replie et à éléments multiples

Similar Documents

Publication Publication Date Title
DE69408846T2 (de) Slab-laser mit gefalteter resonatorstruktur
DE3883130T2 (de) Transversal gepumpter modenangepasster Festkörperlaser mit hohem Wirkungsgrad.
DE60002082T2 (de) Optischer mehrfachdurchgangsverstärker
DE3716873C2 (fr)
DE3813572A1 (de) Laser
DE2018034A1 (de) Flächengepumpter Laser mit vielfacher Innenreflexion
DE102010000032A1 (de) Laserstrahl-Verstärker und Laservorrichtung unter Benutzung desselben
WO2000008726A2 (fr) Systeme d'amplification laser
EP0886896B1 (fr) Laser a ruban
EP0521029B1 (fr) Laser a gaz
EP0355757B1 (fr) Système laser à guide d'ondes
EP2917985B1 (fr) Amplificateur optique slab à pompage par extrémité avec modules de pompage distribués
EP0339128A1 (fr) Laser avec un résonateur à passages multiples
EP0301526B1 (fr) Barreau de laser à matériau solide
DE3604231C2 (fr)
DE3813569A1 (de) Gaslaser
WO1989010641A1 (fr) Laser a gaz
DE7833585U1 (de) Flaechengepumpter laser mit durch beugung begrenztem ausgangsstrahl
DE3330238A1 (de) Hochleistungslaser
DE4123024A1 (de) Laserresonator
DE4129530A1 (de) Laserresonator fuer laser-medien mit ringfoermigem querschnitt
EP0152570B1 (fr) Laser à gaz, en particulier à excitation transversale
EP1151508B1 (fr) Dispositif resonateur comportant au moins deux elements de repliement
DE3923624A1 (de) Verfahren zum betrieb eines gaslasers, insbesondere eines co(pfeil abwaerts)2(pfeil abwaerts)-lasers, mit gasstroemung quer zu seiner optischen achse und gaslaser zur durchfuehrung des verfahrens
WO2000077894A1 (fr) Resonateur d'un laser a activation hf

Legal Events

Date Code Title Description
AK Designated states

Kind code of ref document: A1

Designated state(s): JP US

AL Designated countries for regional patents

Kind code of ref document: A1

Designated state(s): AT BE CH DE FR GB IT LU NL SE