JP2009295690A - Laser oscillation device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a laser oscillation device for efficiently absorbing scattered light from a laser beam and effectively protecting a laser oscillator. <P>SOLUTION: The laser oscillation device includes the laser oscillators A201 or the like, a light guide part for guiding the laser beam irradiated from the laser oscillators to a prescribed optical path, and a protective wall A601 or the like for absorbing the scattered light from the laser beam. Especially the protective wall A601 or the like is formed of an aluminum or an aluminum alloy to which black alumite treatment is performed on the surface. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a laser oscillation device, and more particularly to a laser oscillation device provided with a protective wall.

  In the field of laser processing and the like, a high-power laser oscillation device is used and various types of processing such as cutting, heat treatment, and welding are performed. A laser oscillation device used in such a field needs to have a high output, and there is a reflection / absorption device of a laser processing machine having a configuration for protecting an optical system on the laser oscillator side (for example, Patent Document 1).

  The laser oscillation device according to Patent Document 1 is composed of basic elements of a reflected light absorbing cylinder that absorbs reflected light of a laser beam, a hollow waveguide, and a machining head. Inside, an absorbing means for reflected light is arranged. According to this configuration, the reflected light absorption cylinder is provided with a cooling passage by cooling water, and the reflected light is reflected by the reflected light absorption cylinder, the light shielding plate and the light shielding portion disposed in the path, and the hollow waveguide. Most of them are absorbed, and the optical system on the laser oscillator side can be protected.

However, the laser oscillation device disclosed in Patent Document 1 does not consider the absorption efficiency between the laser wavelength of the laser light and the material of the reflected light absorbing member. Further, when a laser output device having a higher output is configured by combining a plurality of laser oscillators to synthesize a plurality of laser beams, scattered light is generated together with the reflected light, and the laser oscillator is effectively protected from these. There is a need.
JP-A-2-284785

  Accordingly, an object of the present invention is to provide a laser oscillation device that effectively absorbs scattered light from laser light and effectively protects the laser oscillator.

  [1] In order to achieve the above object, the present invention absorbs scattered light from a laser oscillator, a light guide that guides laser light emitted from the laser oscillator to a predetermined optical path, and the laser light. There is provided a laser oscillation device comprising a protective wall.

  [2] The laser oscillation device according to [1], wherein the protective wall is formed of aluminum or aluminum alloy whose surface is black anodized.

  [3] The laser oscillator is mounted on a base provided with a cooling path, and the protective wall is mounted on the base and is exhausted by the cooling path. [1] ] May be used.

  [4] The laser oscillation device according to [1], wherein a plurality of the laser oscillators are arranged, and the laser light is combined by an optical element in the light guide unit.

  [5] The laser oscillation apparatus according to [1], wherein the laser oscillator is a semiconductor laser.

  ADVANTAGE OF THE INVENTION According to this invention, the laser oscillation apparatus which absorbs the scattered light from a laser beam efficiently, and protects a laser oscillator effectively can be provided.

(Laser oscillator configuration)
FIG. 1 is a plan view of a laser oscillation apparatus according to an embodiment of the present invention. 2 is a cross-sectional view taken along the line DD in FIG. FIG. 3 is a diagram showing the relationship between the oscillation wavelength and the absorptance of aluminum.

  The laser oscillation device 1 according to the embodiment of the present invention includes a base 100, and a predetermined position on the base 100 includes a laser oscillator A201, a laser oscillator B202, a laser oscillator C203, a dichroic mirror A301, a dichroic mirror B302, A cylindrical lens 401, a condenser lens 402, a guide light source 403, a shutter 404, a protective wall A601, a protective wall B602, a protective wall C603, and the like are placed. In addition, a cooling water channel 501 for flowing cooling water is provided inside the base 100, and cooling water pipes 502 and 503 are provided on a side surface of the base 100, and a laser oscillator power source 701, and A power source 702 for guide light source is disposed.

  Laser light oscillated by the laser oscillation device 1 is guided to the laser head 802 by the optical fiber 801. The optical fiber 801 and the laser head 802 may be configured integrally with the laser oscillation device 1 or may be configured to be optically connected as necessary using an optical connector or the like.

  The base 100 is plate-shaped, and a cooling water channel 501 is provided inside. As shown by a broken line in FIG. 1, the cooling water channel 501 is arranged so that a deep hole is formed from a side surface portion by a drill or the like and a cooling path passes through a necessary region. The path pattern (cooling path) of the cooling water channel 501 shown in FIG. 1 is an example, and is formed in consideration of the lower part of a laser oscillator described later and exhaust heat efficiency. A cooling water pipe 502 (IN) and a cooling water pipe (OUT) 503 are provided on the side surface of the base 100 as input / output parts of the cooling water channel 501, and cooling water is supplied into the cooling water channel 501 at a predetermined flow rate. Reflux.

  The laser oscillator A201, the laser oscillator B202, and the laser oscillator C203 are high output stacked semiconductor laser oscillators. The oscillation wavelength of the laser oscillator A201 is 980 nm, the oscillation wavelength of the laser oscillator B202 is 940 nm, and the oscillation wavelength of the laser oscillator C203 is 808 nm. In the embodiment of the present invention, three laser oscillators having different oscillation wavelengths are used. However, the present invention is not limited to this configuration, and an arbitrary number of laser oscillators can be used. Even if it is used, it can be used by devising beam synthesis. Laser oscillator A201, laser oscillator B202, and laser oscillator C203 all have a rated output of 960 W, but the output of each oscillator can be arbitrarily selected according to the target output. The laser oscillator A201 is a semiconductor laser, but a carbon dioxide laser or a YAG laser can also be applied.

  Laser light emitted from the laser oscillator A201, the laser oscillator B202, and the laser oscillator C203 is an optical fiber, which will be described later, by a light guide unit including optical elements such as a dichroic mirror A301, a dichroic mirror B302, a cylindrical lens 401, and a condenser lens 402. 801 is guided. The dichroic mirror reflects light of a specific wavelength and transmits light of other wavelengths, and the dichroic mirror A301 transmits 980 nm laser light and reflects 940 nm laser light. The dichroic mirror B302 transmits a laser beam of 940 nm or more and reflects the laser beam of 808 nm.

  The laser light emitted from the laser oscillator A201 passes through the dichroic mirror A301 and the dichroic mirror B302. The laser beam emitted from the laser oscillator B202 is reflected by the dichroic mirror A301, and the reflected laser beam passes through the dichroic mirror B302. The laser beam emitted from the laser oscillator C203 is reflected by the dichroic mirror B302. These three laser beams are combined into one after the dichroic mirror B302. The combined laser beam is shaped by the cylindrical lens 401, collimated by the condenser lens 402, and guided to the optical fiber 801. In FIG. 1, only the chief ray of the laser beam is shown.

  The optical fiber 801 is set to a length capable of guiding laser light from the laser oscillation device 1 to the object to be processed, and uses a glass optical fiber for power transmission. In addition, the laser light from the optical fiber 801 is condensed to a predetermined condensing spot diameter by the laser head 802 and irradiated onto the object to be processed.

  A guide light source 403 and a shutter 404 are provided between the cylindrical lens 401 and the condenser lens 402. Since the laser light emitted from the laser oscillator A201 or the like is not visible light, the guide light source 403 uses a visible light laser of 640 nm, and is used to check the processing point by inserting it into the optical path as necessary. Is done. In addition, a shutter 404 that can be inserted into the optical path is provided so that the laser beam can be shielded as necessary.

  When the laser oscillator A201, the laser oscillator B202, and the laser oscillator C203 are oscillated with the above configuration, part of the reflected light reaches the region other than the predetermined optical path as scattered light. Since the laser oscillator used in the embodiment of the present invention has a high output, the scattered light as described above is condensed on the optical component or the laser oscillator and is damaged. Decreases.

  In order to suppress the above problems, a protective wall is provided at a site where scattered light is collected. In the embodiment of the present invention, the protective wall A601, the protective wall B602, and the protective wall C603 are provided at three locations. However, the present invention is not limited to this, and a required number of protective walls can be provided at necessary locations.

As shown in FIG. 2, the protective wall A 601 is formed in an L shape, for example, and is placed and fixed on a necessary portion on the base 100. The material is preferably aluminum (Al) or an aluminum alloy having excellent thermal conductivity. Here, FIG. 3 shows the relationship between the oscillation wavelength and the light absorption rate of aluminum. Aluminum exhibits a peak of absorption near the wavelength of a near-infrared semiconductor laser, and is excellent in absorption efficiency compared to a YAG laser or a CO ₂ laser. Similarly, the protective wall B602 and the protective wall C603 are formed of aluminum or an aluminum alloy.

The protective walls (A601, B602, C603) are blackened by anodizing the surface in order to improve the absorption of laser light, and a black anodized layer 601a is formed. The alumite treatment is performed by electrolyzing sulfuric acid, oxalic acid or the like as an electrolytic solution, forming an Al ₂ O ₃ film on the surface of aluminum, and adsorbing an inorganic or organic dye (black) on the surface of the film. .

  The protective walls (A601, B602, C603) are placed on the base 100, but are preferably placed on the cooling water channel 501 in particular. As shown in FIG. 2, the scattered light is absorbed by the black alumite layer 601 a of the protective wall A 601, and the heat from the scattered light is transferred through the protective wall A 601 and is exhausted to the base 100. Furthermore, exhaust heat efficiency is improved by exhausting heat to the coolant 504 flowing through the coolant channel 501 in the base 100.

The embodiment of the present invention has the following effects.
(1) In the laser oscillation device 1 according to the embodiment of the present invention, a protective wall is provided at a site where a part of the laser light emitted from the laser oscillator is collected as scattered light. For this reason, it is possible to improve safety by suppressing damage to the optical components and the laser oscillator, overheating of the entire laser oscillator, and the like.
(2) Since the protective wall is made of aluminum (Al) or an alloy material thereof, it has excellent thermal conductivity, and aluminum is near the wavelength of the near-infrared semiconductor laser used in the embodiment of the present invention. Since the absorption peak is exhibited, the light and heat absorption efficiency is excellent.
(3) Since the surface of the protective wall is black anodized, it is possible to improve the absorption of laser light.
(4) Since the protective wall is placed on the cooling water channel 501, exhaust heat efficiency is improved by exhausting heat to the cooling water 504 flowing through the cooling water channel 501 in the base 100.
(5) The laser oscillation apparatus according to the embodiment of the present invention has a configuration in which laser light is synthesized by an optical element in order to achieve particularly high output, and a part of the laser light is scattered during transmission / reflection by the optical element. It tends to be light. However, since the protective wall is provided at the site where the scattered light is collected, it is particularly advantageous for a high-power laser oscillation device.
(6) Since the protective wall is made of aluminum (Al) or its alloy material and the surface is black anodized, it has excellent heat absorption efficiency and thermal conductivity, and it is necessary to cool the protective wall itself with cooling water. There is no need to bring cooling water onto the base 100.
(7) Since the heat absorption efficiency and thermal conductivity of the protective wall are excellent, the protective wall can be made small, and no cooling pipe is required on the base 100, leading to miniaturization of the laser oscillation device.

FIG. 1 is a plan view of a laser oscillation apparatus according to an embodiment of the present invention. 2 is a cross-sectional view taken along the line DD in FIG. FIG. 3 is a diagram showing the relationship between the oscillation wavelength and the absorptance of aluminum.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Laser oscillation apparatus, 100 ... Base, 201 ... Laser oscillator A, 202 ... Laser oscillator B, 203 ... Laser oscillator C, 301 ... Dichroic mirror A, 302 ... Dichroic mirror B, 401 ... Cylindrical lens, 402 ... Condenser lens, 403 ... Guide light source, 404 ... Shutter, 501 ... Cooling water channel, 502, 503 ... Cooling water piping, 504 ... Cooling water, 601 ... Protective wall A, 601a ... Black anodized layer, 602 ... Protective wall B, 701 ... Laser oscillator Power source 702 ... Power source for guide light source, 801 ... Optical fiber, 802 ... Laser head

Claims (5)

A laser oscillator;
A light guide that guides laser light emitted from the laser oscillator to a predetermined optical path;
A protective wall for absorbing scattered light from the laser light;
A laser oscillation device comprising:   2. The laser oscillation device according to claim 1, wherein the protective wall is formed of aluminum or an aluminum alloy having a black anodized surface.   2. The laser oscillation according to claim 1, wherein the laser oscillator is placed on a base provided with a cooling path, and the protective wall is placed on the base and is exhausted by the cooling path. apparatus.   The laser oscillation apparatus according to claim 1, wherein a plurality of the laser oscillators are arranged, and the laser light is synthesized by an optical element in the light guide unit.   The laser oscillation apparatus according to claim 1, wherein the laser oscillator is a semiconductor laser.

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