DD251097A1 - Optical system for introducing laser radiation - Google Patents

Optical system for introducing laser radiation Download PDF

Info

Publication number
DD251097A1
DD251097A1 DD29264186A DD29264186A DD251097A1 DD 251097 A1 DD251097 A1 DD 251097A1 DD 29264186 A DD29264186 A DD 29264186A DD 29264186 A DD29264186 A DD 29264186A DD 251097 A1 DD251097 A1 DD 251097A1
Authority
DD
German Democratic Republic
Prior art keywords
mirror
laser beam
focusing optics
surface
laser beams
Prior art date
Application number
DD29264186A
Other languages
German (de)
Inventor
Guenter Reisse
Horst Exner
Gerhard Zscherpe
Ulf Seifert
Original Assignee
Mittweida Ing Hochschule
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
Application filed by Mittweida Ing Hochschule filed Critical Mittweida Ing Hochschule
Priority to DD29264186A priority Critical patent/DD251097A1/en
Publication of DD251097A1 publication Critical patent/DD251097A1/en

Links

Abstract

The invention relates to a device for Laserstrahlfuehrung for laser material processing. The object and the object to be solved of the invention consist in the complete guiding into one another of laser beams for the simultaneous processing of a given area of a material surface. According to the invention, a first laser beam is focused by means of a first focusing optical system into the opening of the reflecting surface of a mirror inclined to the optical axis of the system for a second laser beam. The laser beams, which are guided into one another, are directed onto the workpiece surface to be machined with the aid of a second focusing optical system. The invention is applicable in the field of laser beam technology, in particular for modifying Festkoerperoberflaechen and for drilling, cutting and joining means laser beams.

Description

For this 3 pages drawings

Fields of application of the invention

The invention is applicable in the field of laser beam technology, in particular for the laser beam-induced modification of the surface area of solid bodies as well as for drilling, cutting and joining by means of laser beams.

Characteristic of the known technical solutions

The laser processing of materials which have a low thermal shock resistance is often possible without the production of defects, such as cracks, in the processing areas only when a larger area than the immediate processing area is preheated by suitable means. As means for preheating, for example, laser beams are also suitable (DD B23 K26 / 00 231522), which are directed by means of optical devices simultaneously with the laser beam used for processing on the processing area. An optimal energy input into the material surface and a uniform radially symmetrical power density distribution on the material surface can be achieved if the laser beams used for machining and for preheating are guided into one another and thus have identical or parallel optical axes.

Methods are already known for guiding one another or for splitting laser beams, wherein the laser beams introduced into one another have the same and the sub-beams have parallel optical axes. In the patent EP G 02 B 27/14 0059836 is a cylindrical laser beam with the aid of a tilted by 45 ° to the beam axis mirror with an opening in Strahlauftreffzentrum in a hollow cylindrical part of the beam and in the opening cross section corresponding cylindrical partial beam, with the help of another 45 ° Mirror is directed parallel to the hollow cylindrical partial beam, disassembled.

Due to the invariance of the beam directions in optical systems, the same arrangement is also suitable for guiding laser beams into one another; in the patent specifications DE B23 K26 / 00 2708039 and DE B23 K26 / 00 2713904 this possibility is disclosed.

The disadvantages of the merging of two laser beams by means of this arrangement is that the opening in the 45 ° mirror must be adapted to the cross section of the continuous laser beam, whereby the cross section of the opening corresponding intensity of the mirror reflected laser beam after the interfitting is no longer available if this beam was cylindrical before the reflection. To avoid this loss of intensity of the reflected beam can be formed before the reflection hollow cylindrical, for example by means of a mirror optics according to DE G 02 B17 / 00 3504366 A1, whereby, however, the optical parameters of the laser beam are reduced and the cost of the entire arrangement is much higher.

Furthermore, the laser beams interspersed with this arrangement can only be jointly focused or defocused by subsequently arranged optics, the portion of the merged-in beam reflected by the mirror having a ring-shaped intensity profile in the defocused state on the material surface to be processed. In one embodiment of the patent DE B23 K26 / 00 2713904 an optics is described, which allows to focus a part of the merged beams and to defocus another part; However, the production of this optics is complicated and the cooling of such a design for (^ laser beams problematic.

Object of the invention

It is the object of the invention to reduce the deficiency of the known technical solutions and to completely merge cylindrical laser beams.

Explanation of the essence of the invention

The invention has for its object to develop a device for complete merging of laser beams for the simultaneous processing of a predetermined range of a material surface, wherein the focal spot radius of the individual laser beams is variable independently.

The causes of the deficiencies of the known technical solutions are that both laser beams are formed by the 45 ° to the beam axis of the passing through the mirror opening laser beam as a parallel beam before merging. For this reason, independent variation of the focal spot radii of the merged beams by means of available optics is not possible, and the beam reflected from the 45 ° mirror produces an annular focal spot on the material surface out of focus.

For the laser material processing with preheating by a second laser beam, however, it is necessary that the preheated area of the material surface area and thus the focal spot radius of the preheat beam is chosen substantially larger than the focal spot radius of the laser beam used for processing.

According to the invention the object is achieved by a device consisting of at least two highly reflective laser beams used and two highly transparent focusing optics in that the focal length of a first focusing optics for a first, parallel laser beam in the opening of the mirror surface of a first, to the optical axis the first focusing optics inclined mirror for a second unfocused laser beam, whereby this mirror merges both laser beams, and that both laser beams after common passage through a second focusing, highly transparent to the laser beams used optics, which hereinafter referred to as the optical axis of the system optical axis as the first focusing optics has, are directed to the workpiece surface to be machined.

In a further embodiment of the invention serves as the first focusing optics inclined to the optical axis of the system concave mirror, and as the second focusing optics of the also designed as a concave mirror, the two laser beams into one another and inclined to the optical axis of the system mirror is used. The optically effective surface of both mirrors is shaped so that the laser beams are deflected, guided parallel to the optical axis of the system and focused in the predetermined focal points.

In order to position the second, non-focusing laser beam on the first mirror, a second mirror is displaceably mounted parallel to this and parallel to the optical axis of the system. The predetermined displacement of the second mirror relative to the first one achieves the effect that both laser beams optionally have the same optical axis or optical axes which are aligned parallel to one another and spaced apart by a predetermined amount, whereby the defined introduction of a predetermined energy fluence of each laser beam into the laser beam Solid surface can be done simultaneously or sequentially.

embodiment

The device will be explained in more detail below with reference to three exemplary embodiments. The accompanying drawings show:

Fig. 1: The supply of the laser beam used for processing as reflected by the merging 45 ° mirror

Beam Fig. 2: The feeding of the laser beam used for the processing as the through the opening of the ineinanderführenden

45 ° mirror continuous beam Fig. 3: The focusing of the laser beams by means of reflecting concave mirrors

In the Ausführungsbeispiei of Fig. 1 of the laser 2 generated and used for processing laser beam 3 of a fixed mirror 5 and a parallel to the optical axis of the system displaceable mirror 13 on the nested mirror 9, which is parallel to the optical axis of the system displaceable is mounted, steered, reflected by the mirror 9 in the direction of the optical axis of the system and by means of the optics 10, which are also parallel to the optical axis

of the system is slidable and located in the range of the distance of its focal length from the opening in the merging mirror 9 and the surface of the workpiece 11 to be machined, focused on the surface of the workpiece 11 to be machined, which is positioned on an xy-coordinate table 12.

The laser beam 4 generated by the laser 1 and used for preheating the surface area to be processed is reflected by a fixed mirror 6 in the direction of the optical axis of the system, focused by means of the optics 7 in the opening of the mirror surface of the mirror 9 and by the mirror Optics 10 shown on the surface of the workpiece to be machined 9 so that the focal spot of the laser beam 3 is within the focal spot of the laser beam 4 on the workpiece surface. The optical system 7 is fixedly connected to the mirror 9 in order to fix the focal position of the laser beam 4 in the opening of the reflecting surface of the mirror 9. The diameter of the opening in the mirror 9 can thus be chosen to be comparable with the focus diameter of the laser beam 4, so that the non-reflected portion of the laser beam 3, which is absorbed by the beam absorber 8, is negligibly small.

In order to vary the power flux density of the laser beam 3 on the workpiece surface, the optics 10, the mirror 9 with the optics 7 and the mirror 13 are displaced simultaneously by the same amount a = b = c. The power flux density of the laser beam 4 on the workpiece surface is variable by the simultaneous displacement of the mirrors 9 and 13 by the same amount a = c. By shifting the mirror 13 by the amount c, the position of the focal spot of the laser beam 3 with respect to the focal spot center of the laser beam 4 on the material surface is shifted by the same amount c. In the embodiment of FIG. 2, the same arrangement of the optical components as in the embodiment of FIG. 1 is used. The distances between the mirror 9, the optics 10 and the surface of the workpiece 11 and the focal length of the optics 10 are chosen so that in contrast to the embodiment of FIG. 1, the laser beam 4 for processing and the laser beam 3 for preheating the material surface can be used. This is possible if the distance of the focusing optics 10 from the opening in the merging mirror 9 and from the surface of the workpiece 11 is in the range of twice the focal length of the focusing optics 10.

In the embodiment of FIG. 3, the mirrors 6 and 9 as a concave mirror with varying over the reflecting surface radii of curvature, formed and arranged so that the laser beam used for preheating 4 by means of the mirror 6 in the opening of the nested mirror 9 and the The laser beam 3 used for processing can be focused on the surface of the workpiece 11 to be machined with the aid of the mirror 9, the distance of the mirror 6 from the opening in the mirror 9 is thus equal to the focal length of the mirror 6, and the distance of the mirror 9 from the mirror Surface of the workpiece to be machined is in the range of the focal length of the mirror. 9

In order to vary the power flux density of the laser beam 3 on the surface of the workpiece 11, the mirrors 6, 9, 14 and the mirror 13 fixedly connected to one another are displaced parallel to the optical axis of the system by the same amount a = c; At the same time, the power flux density of the laser beam 4 changes by a small amount.

Claims (4)

1. An optical system for merging laser beams using highly reflective for the laser beam used mirrors and focusing optics, characterized in that the focal length of a first highly transparent focusing optics for a first laser beam in the opening of the reflective surface of a first highly reflective, to the optical axis of Systems inclined mirror for a second laser beam, and that both the laser beams are directed to the surface of the workpiece to be machined after passing through a second highly reflective focusing optics, which has the same optical axis as the first focusing optics, or that (further optional) serves as a first focusing optics inclined to the optical axis of the system, highly reflective concave mirror and serves as a second focusing optics of the likewise designed as a concave mirror first highly reflective, the laser beams inei nanderführ mirror is used, that for positioning the second laser beam on the first mirror parallel to this and parallel to the optical axis of the system slidably mounted a second mirror and that both laser beams either the same optical axis or aligned parallel to each other in their distance from each other have a predetermined amount shifted optical axes.
2. An optical system according to claim 1, characterized in that the distance of the second highly transparent focusing optics (10) from the opening in the first, designed as a plane mirror nested mirror (9) and from the surface of the workpiece (11) is variable and preferably in Range of the focal length of the second focusing optics (10).
3. An optical system according to claim 1, characterized in that the distance of the second focusing optics (10) from the opening in the first, designed as a plane mirror nested mirror (9) and from the surface of the workpiece (11) is variable and preferably in the area is twice the focal length of the second focusing optics (10).
4. An optical system according to claim 1, characterized in that the distance of the designed as focussing optics mirror (6) of the opening in the merging mirror (9) equal to the focal length of the mirror (6) and the distance of the mirror also designed as focussing optics (9) from the surface of the workpiece (11) in the region of the focal length of the mirror (9).
DD29264186A 1986-07-18 1986-07-18 Optical system for introducing laser radiation DD251097A1 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
DD29264186A DD251097A1 (en) 1986-07-18 1986-07-18 Optical system for introducing laser radiation

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
DD29264186A DD251097A1 (en) 1986-07-18 1986-07-18 Optical system for introducing laser radiation

Publications (1)

Publication Number Publication Date
DD251097A1 true DD251097A1 (en) 1987-11-04

Family

ID=5581010

Family Applications (1)

Application Number Title Priority Date Filing Date
DD29264186A DD251097A1 (en) 1986-07-18 1986-07-18 Optical system for introducing laser radiation

Country Status (1)

Country Link
DD (1) DD251097A1 (en)

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE4034744A1 (en) * 1989-10-30 1991-07-18 Univ Schiller Jena Variable laser beam division - has modulator and mirror assembly to alter power ratios and alignment rapidly
DE19601032C1 (en) * 1996-01-13 1997-04-10 Univ Schiller Jena Laser working device for brittle material
DE19805726A1 (en) * 1998-02-12 1999-09-02 Fraunhofer Ges Forschung Method of increasing the process stability of laser material processing
DE19619339B4 (en) * 1995-05-26 2005-02-24 BLZ Bayerisches Laserzentrum Gemeinnützige Forschungsgesellschaft mbH Laser beam processing device with two partial beams
CN104755013A (en) * 2012-10-25 2015-07-01 极点有限公司 Image acquisition apparatus

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE4034744A1 (en) * 1989-10-30 1991-07-18 Univ Schiller Jena Variable laser beam division - has modulator and mirror assembly to alter power ratios and alignment rapidly
DE4034744C2 (en) * 1989-10-30 1998-09-24 Univ Schiller Jena Device for variable laser beam division and guidance of the partial beams
DE19619339B4 (en) * 1995-05-26 2005-02-24 BLZ Bayerisches Laserzentrum Gemeinnützige Forschungsgesellschaft mbH Laser beam processing device with two partial beams
DE19601032C1 (en) * 1996-01-13 1997-04-10 Univ Schiller Jena Laser working device for brittle material
DE19805726A1 (en) * 1998-02-12 1999-09-02 Fraunhofer Ges Forschung Method of increasing the process stability of laser material processing
CN104755013A (en) * 2012-10-25 2015-07-01 极点有限公司 Image acquisition apparatus

Similar Documents

Publication Publication Date Title
US4275288A (en) Apparatus for machining material
JP3531199B2 (en) Optical transmission equipment
US5705788A (en) Process for treatment of materials with diode radiation
EP0997261B1 (en) Laser welding method and apparatus for joining a plurality of plastic articles with each other or with other materials
US4566765A (en) Apparatus for summing several ring-shape laser beams
ES2215939T3 (en) System and procedure for welding laser distance.
US5779753A (en) Method of and apparatus for treating a solid workpiece, especially a glass tube
EP0243293B1 (en) Twin spot laser welding
US7151788B2 (en) Laser processing device
JP5383504B2 (en) Laser beam welding apparatus and laser beam welding method
US5841097A (en) Process and apparatus for welding workpieces with two or more laser beams whose spots are oscillated across welding direction
DE10193737B4 (en) Laser processing device
JP2004136675A (en) Method and device for joining article of synthetic resin in three-dimensional shape
EP0929376B2 (en) A method of processing a material by means of a laser beam
EP0882540B1 (en) Optical device for laser machining
US20170368638A1 (en) Material processing utilizing a laser having a variable beam shape
US4456811A (en) Method of and apparatus for heat treating axisymmetric surfaces with an annular laser beam
ES2423952T3 (en) Mechanization device with laser beam with means for the representation of annularly reflected laser radiation on a sensor unit as well as a procedure for adjusting the focal position
EP0594210B2 (en) Method and apparatus for welding material by laser beam
US6331692B1 (en) Diode laser, laser optics, device for laser treatment of a workpiece, process for a laser treatment of workpiece
DE3037981C2 (en)
JP2006218487A (en) Laser welding equipment, laser welding system, and laser welding method
EP0282593B1 (en) Laser beam forming apparatus
KR930004999B1 (en) Laser processing device
ES2248672T3 (en) Laser welding procedure for structured plastics.

Legal Events

Date Code Title Description
ENJ Ceased due to non-payment of renewal fee