JP5389554B2 - Laser apparatus and laser beam adjustment method - Google Patents

Description

  The present invention relates to a laser device using an optical fiber and a laser beam adjusting method.

  Conventionally, as a method for increasing the output of laser light, for example, a method of connecting a plurality of oscillators is known. In order to combine laser beams emitted from a plurality of oscillators, a method of using a bundle fiber in which a plurality of optical fibers are bundled with an adhesive or the like, or a method in which a plurality of optical fibers are bundled and fused to form a single fiber. A method for forming an optical fiber is widely known. However, when the bundle fiber is used, the adhesive may burn out due to the heat generated by the laser light propagating in the optical fiber, and the beam quality of the laser light may deteriorate. Further, when fusing a plurality of optical fibers, it is difficult to bundle, for example, optical fibers having a diameter of 100 μm or less.

  In order to obtain high-power laser light while eliminating the above problems, three laser lights are condensed at one point by one optical fiber incidence lens and incident on the optical fiber to propagate through the optical fiber. The laser beam synthesized in this way is collected by a processing optical system to process a workpiece (see Patent Document 1), or four laser beams are condensed on the end face of a clad excitation laser fiber by a convex lens. A laser device (see Patent Document 2) that emits a high-power laser beam by exciting a rare earth element doped in the core of a clad excitation laser fiber is known.

JP-A-11-231175 JP 2003-309309 A

  Patent Document 1 does not clearly describe the incident positions of the three laser beams with respect to the optical fiber incident lens. For this reason, in Patent Document 1, when any one of the three laser beams is incident on the center of the optical fiber incident lens, the laser beam emitted from the optical fiber has a circular cross section. The beam profile of the laser beam at the point has a Gaussian distribution. When processing a workpiece made of a material having a high thermal conductivity such as aluminum using a laser beam having such a Gaussian beam profile, the intensity of the central portion of the laser beam is high at the processing point. Therefore, a keyhole may be formed in a part of the workpiece. In the processing in which the keyhole is formed in this way, splash (scattering) occurs during laser processing. There is a possibility that the material scattered by the splash may reattach to the processing point or the vicinity thereof. Even when the workpiece is melt-processed using the apparatus of Patent Document 2, the beam profile at the processing point has a Gaussian distribution, so that a keyhole can be formed.

  SUMMARY OF THE INVENTION An object of the present invention is to provide a laser apparatus and a laser beam adjusting method that can melt a workpiece while suppressing the formation of keyholes.

  A laser apparatus according to a first aspect of the present invention includes a laser light output unit that outputs laser light, a condensing lens that condenses the laser light output from the laser light output unit, and a light that is collected by the condensing lens. An optical fiber having a core on which the laser light is incident, and the laser light output from the laser light output unit is incident on a position off the center of the condenser lens and is condensed by the condenser lens The laser light output unit, the condensing lens, and the optical fiber are set so that the laser light that has been incident is incident in a state of intersecting with a perpendicular to the end face of the core.

  When a workpiece made of a material with high thermal conductivity such as aluminum is melted with a laser beam, the laser beam is usually focused on the workpiece with a condenser lens for processing while being collimated with a collimator lens. It is.

  According to the laser device of the first aspect of the present invention, the laser beam output from the laser beam output unit is incident on a position off the center of the condenser lens, and the laser beam condensed by the condenser lens is emitted as light. Since it is incident on the core of the optical fiber in a state of being intersected with a normal to the end face of the fiber, the laser light incident on the core of the optical fiber propagates while being reflected many times in the core. For this reason, the laser light emitted from the optical fiber has a donut shape in cross section in a state where it is collimated by the collimating lens. Accordingly, since the laser beam having a donut cross section is focused on the workpiece by the processing condensing lens, the beam profile of the laser beam becomes a top hat shape at the processing point. That is, the laser beam at the processing point has a wide profile in the radial direction in which the intensity of the central portion is suppressed. Thereby, the workpiece can be melt processed while suppressing the formation of the keyhole. Therefore, it is possible to prevent the occurrence of splash during laser processing.

  A laser apparatus according to a second aspect of the present invention includes a laser beam output unit that outputs three laser beams, a condensing lens that collects the three laser beams output from the laser beam output unit, and the collector An optical fiber having a core on which a laser beam condensed by an optical lens is incident, and an optical path between the laser beam output unit and the focusing lens, and three laser beams output from the laser beam output unit Optical path adjusting means for adjusting the optical path of the laser light so that each of the laser light is incident on another position off the center of the condenser lens, and the laser light condensed by the condenser lens is The condensing lens and the optical fiber are set so as to be incident in a state of intersecting with a perpendicular to the end face of the core.

  According to the laser device of the second aspect of the present invention, each of the three laser beams output from the laser beam output unit is incident on another position off the center of the condenser lens. Can be produced easily, and the same effects as those of the laser apparatus according to the first aspect of the present invention described above can be obtained.

  In an embodiment of the laser apparatus according to the first aspect of the present invention, the laser beam output unit is configured to output a plurality of laser beams, and is disposed between the laser beam output unit and the condenser lens. And an optical path for adjusting the optical path of the laser beam so that each of the plurality of laser beams output from the laser beam output unit is incident on another position off the center of the condenser lens Adjustment means may be further provided.

  According to this embodiment, a high output laser beam can be easily generated by using a plurality of laser beams.

  In an embodiment of the laser apparatus according to the second aspect of the present invention, the optical path adjustment means is incident on the condenser lens in a state where the three laser beams output from the laser beam output unit are spaced equiangularly in the circumferential direction. As described above, the optical path of the laser beam may be adjusted.

  According to this aspect, since the three laser beams are incident on the condenser lens in a state of being spaced apart at equal angles in the circumferential direction, the condenser lens is in a state of being separated from each other by equal angles in the circumferential direction. As compared with the case where the laser beam is incident on the laser beam, the intensity distribution of the laser light having a donut-shaped cross section made parallel by the collimator lens can be made more uniform. Thereby, formation of the keyhole to a workpiece | work can be suppressed effectively.

  The laser beam adjustment method according to the present invention is a laser beam adjustment method in which three laser beams output from a laser beam output unit are collected on a core of an optical fiber by a condensing lens. Each of the three laser beams output from the output unit is incident on a different position off the center of the condenser lens, and the laser beam condensed by the condenser lens is perpendicular to the end surface of the core. It is characterized by being incident in a crossed state.

  According to the laser beam adjustment method of the present invention, the same effects as those of the laser device of the second present invention described above can be obtained.

  As described above, according to the present invention, the laser beam output from the laser beam output unit is incident on a position off the center of the condenser lens, and the laser beam condensed by the condenser lens is optical fiber. Since the laser beam emitted from the optical fiber is collimated by the collimator lens, the cross-sectional donut shape is incident on the core of the optical fiber in a state of crossing the perpendicular to the end surface of the core. It becomes. Accordingly, since the beam profile of the laser beam has a top hat shape at the processing point, the workpiece can be melt processed while suppressing the formation of the keyhole.

It is the block diagram which showed the principal part of the laser apparatus concerning embodiment of this invention. It is a block diagram which shows the internal structure of the adjustment mechanism shown in FIG. It is the block diagram which looked at the adjustment mechanism shown in FIG. 2 from the arrow Y direction of FIG. It is front explanatory drawing of the condensing lens provided in the said adjustment mechanism. FIG. 4 is a schematic cross-sectional explanatory view of the synthetic fiber shown in FIGS. 2 and 3. It is a schematic cross-sectional explanatory drawing of the emitted light collimated by the collimating lens. It is a characteristic curve figure which shows the temperature distribution of the condensing lens for a process. It is a schematic cross-sectional explanatory drawing along the transmission direction of the emitted light of the processing condensing lens.

  An embodiment of a laser apparatus according to the present invention will be described with reference to FIGS.

  The laser apparatus according to the present embodiment is an apparatus that emits high-power laser light by combining a plurality of laser lights with an optical fiber, and is used for processing, welding, cutting, or the like of a workpiece. In addition, as a workpiece | work, metal materials with high heat conductivity, for example, aluminum, an aluminum alloy, copper, a copper alloy, etc. can be used.

  As shown in FIG. 1, the laser device 10 includes a laser beam output unit 12 that outputs three laser beams, a transmission unit 14 that transmits three laser beams, and three laser beams transmitted by the transmission unit 14. Are combined with a single laser beam, a light emitting unit 20 for condensing the combined laser beam on a processing target portion of the workpiece 18, and a control unit 22.

  The laser beam output unit 12 includes a first unit 24a that outputs the first fiber laser beam FB1, a second unit 24b that outputs the second fiber laser beam FB2, and a third unit 24c that outputs the third fiber laser beam FB3. And an LD power source 30.

  The first unit 24a is provided with a laser diode (LD) 32a that outputs the pumping light MB and a fiber laser light output unit 34a that outputs the first fiber laser light FB1 based on the pumping light MB. The fiber laser light output unit 34a collimates the optical fiber (active fiber) 36a that outputs the first fiber laser light FB1 by the propagation of the pumping light MB and the first fiber laser light FB1 output from the active fiber 36a. A collimating lens 38a, an isolator 40a that prevents the reflected light reflected by the transmission unit 14 from being irradiated on the LD 32, and a condensing lens 42a that condenses the first fiber laser light FB1 that has passed through the isolator 40a.

  The second unit 24b has the same configuration as the first unit 24a, and includes an LD 32b and a fiber laser light output unit 34b that outputs the second fiber laser light FB2, and the fiber laser light output unit 34b includes an active A fiber 36b, an isolator 40b, and a condenser lens 42b are provided.

  The third unit 24c has the same configuration as the first unit 24a, and includes an LD 32c and a fiber laser light output unit 34c that outputs the third fiber laser light FB3. The fiber laser light output unit 34c includes an active A fiber 36c, an isolator 40c, and a condenser lens 42c are provided.

  The active fibers 36a, 36b, and 36c include a core (not shown) doped with a rare earth element ion such as ytterbium (Yb), and the first fiber laser beam is excited by exciting the rare earth element ion with the excitation light MB. FB1 is output. The LD power source 30 supplies an excitation current to the LDs 32a, 32b, and 32c of the first to third units 24a, 24b, and 24c.

  The transmission unit 14 includes a first transmission fiber 46a that transmits the first fiber laser beam FB1 to the combining unit 16, a second transmission fiber 46b that transmits the second fiber laser beam FB2 to the combining unit 16, and a third fiber laser beam. And a third transmission fiber 46c for transmitting FB3 to the combining unit 16. Hereinafter, the first to third fiber laser beams FB1, FB2, and FB3 may be collectively referred to as a fiber laser beam FB.

  The combining unit 16 includes an adjustment mechanism 52 that optically adjusts the optical path of the fiber laser light FB transmitted through the first to third transmission fibers 46a, 46b, and 46c, and a fiber laser that has been adjusted in optical path by the adjustment mechanism 52. And an optical fiber (synthetic fiber) 54 for synthesizing the optical FB.

  As shown in FIGS. 2, 3, and 5, the adjustment mechanism 52 includes a housing 56 for supporting the first to third transmission fibers 46 a, 46 b, 46 c and the synthetic fiber 54, and the first to third transmissions. And an optical member 60 for guiding the fiber laser light FB emitted from the fibers 46a, 46b, and 46c to the core 72 of the synthetic fiber 54. Although not shown, the adjustment mechanism 52 is configured so that the first to third transmission fibers 46a, 46b, 46c, the synthetic fiber 54, and the optical member 60 can be cooled. The adjustment mechanism 52 is cooled by, for example, water cooling. Thereby, it is possible to prevent the optical member 60 and the like from being defective due to heat resulting from the reflection / scattering of the fiber laser light FB and the optical path of the fiber laser light FB from being shifted.

  Further, as shown in FIG. 2, the emission end faces of the first to third transmission fibers 46 a, 46 b, 46 c and the incident end face 61 of the synthetic fiber 54 face the housing 56, and the first to third transmission fibers Antireflection treatment is applied to the emission end faces of 46a, 46b, and 46c, the incident end face 61 of the synthetic fiber 54, and the optical member 60. As this antireflection treatment, for example, AR coating or the like is used. Thereby, it is possible to prevent the fiber laser beam FB from being reflected by the emission end surfaces of the first to third transmission fibers 46 a, 46 b, 46 c and the incident end surface 61 of the synthetic fiber 54 to generate heat in the housing 56.

  As shown in FIG. 2, the housing 56 emits the first fiber laser beam FB1 in the X direction, the second and third fiber laser beams FB2 and FB3 in the Y direction, and as shown in FIG. In the Z direction, the first and third fiber laser beams FB1 and FB3 are aligned so that the second fiber laser beam FB2 is positioned above the first and third fiber laser beams FB1 and FB3. The third transmission fibers 46a, 46b, and 46c are supported. As shown in FIGS. 2 and 3, the housing 56 supports the synthetic fiber 54 so that the emission end face of the first transmission fiber 46 a and the incident end face 61 of the synthetic fiber 54 face each other in the X direction.

  As shown in FIGS. 2 and 5, the optical member 60 emits the fiber laser light FB from the condensing lens 62 that condenses the fiber laser light FB onto the core 72 of the synthetic fiber 54 and the first to third transmission fibers 46a, 46b, and 46c. And an optical path adjusting unit 64 as optical path adjusting means for guiding the fiber laser beam FB thus obtained to the condenser lens 62. As shown in FIGS. 2 and 3, the condenser lens 62 faces the incident end face 61 of the synthetic fiber 54 in a state of being separated from the synthetic fiber 54 by a predetermined distance.

  As shown in FIGS. 2 and 3, the optical path adjustment unit 64 includes collimator lenses 66a, 66b, and 66c provided on each optical path of the fiber laser light FB, and a mirror for adjusting the optical path of the second fiber laser light FB2. 68 and a mirror 70 for adjusting the optical path of the third fiber laser beam FB3.

  As shown in FIG. 2, the mirrors 68 and 70 are set so that the fiber laser light FB is incident on the condenser lens 62 in the state of being offset at equal intervals in the Y direction. As a result, as shown in FIG. 4, each of the fiber laser beams FB is made incident at different positions off the center N of the condenser lens 62. Specifically, the fiber laser beam FB is incident on the condenser lens 62 in the circumferentially spaced state, and the angle θ12 formed by the line segment A1 and the line segment A2, and the angle θ13 formed by the line segment A1 and the line segment A3. The angle θ23 formed by the line segment A2 and the line segment A3 is set to 120 ° (that is, equal angle). The angle θ12, the angle θ13, and the angle θ23 can be set to substantially equal angles with a difference of several degrees without being accurately set to equal angles.

  A line segment A1 is a line segment connecting the incident position of the first fiber laser beam FB1 of the condenser lens 62 and the center N of the condenser lens 62, and a line segment A2 is the second fiber laser beam of the condenser lens 62. The line segment connecting the incident position of FB2 and the center N of the condenser lens 62, and the line segment A3 is a line connecting the incident position of the third fiber laser beam FB3 of the condenser lens 62 and the center N of the condenser lens 62. Minutes. Further, the distance between the center N of the condenser lens 62 and the incident position of each fiber laser beam FB of the condenser lens 62 is set at an equal distance.

  As shown in FIGS. 2, 3, and 5, in the synthetic fiber 54 and the condensing lens 62, the fiber laser light FB that has passed through the condensing lens 62 intersects the perpendicular L of the incident end face 61 of the synthetic fiber 54. In this state, it is set so as to be condensed at the center of the core 72 of the synthetic fiber 54. In addition, the synthetic fiber 54 and the condensing lens 62 include an angle formed between the first fiber laser beam FB1 and the perpendicular L of the incident end surface 61, and an angle formed between the second fiber laser beam FB2 and the perpendicular L of the incident end surface 61. The angle formed by the third fiber laser beam FB3 and the perpendicular L of the incident end face 61 is set to be the same angle. An angle formed by each of the fiber laser beams FB and the perpendicular L is α. However, the angle α may be set arbitrarily.

  As shown in FIG. 5, the synthetic fiber 54 includes a core 72 that extends on the central axis of the synthetic fiber 54, a clad 74 that is provided coaxially with the core 72 and surrounds the core 72, and a coating 76 that covers the clad 74. Have.

  As shown in FIG. 1, the emitting unit 20 includes a collimating lens 78 that collimates the laser light (emitted light) PB emitted from the synthetic fiber 54, and the emitted light PB that has passed through the collimating lens 78. And a processing condensing lens 80 for condensing light on the part.

  The control unit 22 controls the LD power supply 30 so that the excitation current supplied to each of the LDs 32a, 32b, and 32c of the first to third units 24a, 24b, and 24c is adjusted according to the required energy of the emitted light PB. .

  Next, the basic operation of the laser device 10 will be described. First, when an excitation current is supplied from the LD power source 30 to each of the LDs 32a, 32b, and 32c under the action of the control unit 22, the excitation light MB is output from the LDs 32a, 32b, and 32c, and the output excitation light MB is converted into an active fiber. The fiber laser beams FB1, FB2, and FB3 are output from the active fibers 36a, 36b, and 36c by propagating through the fibers 36a, 36b, and 36c. The fiber laser beams FB1, FB2, and FB3 output from the active fibers 36a, 36b, and 36c are first through the collimating lenses 38a, 38b, and 38c, the isolators 40a, 40b, and 40c, and the condenser lenses 42a, 42b, and 42c. The light is transmitted to the adjustment mechanism 52 through the third transmission fibers 46 a, 46 b and 46 c, and is incident on the condenser lens 62 through the optical path adjustment unit 64. At this time, each of the fiber laser beams FB 1, FB 2, and FB 3 is incident on another position off the center N of the condenser lens 62.

  Then, the fiber laser light FB incident on the condensing lens 62 is condensed on the core 72 of the synthetic fiber 54 in a state of crossing the perpendicular L of the incident end face 61 of the synthetic fiber 54, and the inside of the synthetic fiber 54 is cored. The reflected light propagates through the boundary surface between 72 and the clad 74 many times and is emitted from the synthetic fiber 54. The outgoing light PB emitted from the synthetic fiber 54 is collimated by the collimator lens 78. At this time, the collimated outgoing light PB has a donut shape in cross section (see FIG. 6). Even at the position between the synthetic fiber 54 and the collimating lens 78, the emitted light PB has a donut shape in cross section. Then, the collimated exit light PB having a cross-sectional donut shape is condensed on the processing target portion of the workpiece 18 by the processing condensing lens 80. Thereby, the workpiece 18 is processed.

  As described above, according to the laser device 10 according to the present embodiment, the exit light PB having a cross-sectional donut shape is condensed on the processing target portion of the workpiece 18 by the processing condensing lens 80. , The beam profile of the outgoing light PB has a top hat shape. That is, the outgoing light PB at the processing point has a wide profile in the radial direction in which the intensity of the central portion is suppressed. Thereby, the workpiece 18 can be melt processed while suppressing the formation of the keyhole. Therefore, it is possible to prevent the occurrence of splash in the laser.

  In the present embodiment, since the laser light output unit 12 is configured so that the three fiber laser beams FB are output, the high-output emitted light PB can be easily generated.

  Furthermore, in this embodiment, since the fiber laser light FB is incident on the condenser lens 62 in a state where the fiber laser light FB is separated by 120 ° in the circumferential direction, the fiber laser light FB is collected in a state where the fiber laser light FB is not evenly spaced in the circumferential direction. Compared with the case where the light is incident on the optical lens 62, the intensity distribution of the outgoing light PB having a donut-shaped cross section parallelized by the collimator lens 78 can be made more uniform. Thereby, formation of the keyhole of the workpiece | work 18 can be suppressed effectively.

  By the way, when a plurality of fiber laser beams are incident on the center of the condenser lens, the outgoing light collimated by the collimator lens has a circular cross section. When the emitted light having a circular cross section is condensed on the workpiece by the processing condensing lens, the processing condensing lens receives a great amount of heat when the emitted light passes through the processing condensing lens. At this time, the heat received from the light emitted from the processing condenser lens diffuses radially around the optical axis of the processing condenser lens, so that the optical axis (processing condenser) of the processing condenser lens is diffused. The temperature is highest at the center of the lens.

  Thereby, compared with the refractive index of the emitted light which permeate | transmits the center of this processing condensing lens when it is assumed that the said processing condensing lens does not receive heat from emitted light, it received heat from emitted light. Since the refractive index of the outgoing light that passes through the central portion of the processing condenser lens at the time increases, the focal position of the outgoing light that has passed through the processing condenser lens may shift (hereinafter, this phenomenon will be Sometimes referred to as the lens effect.)

  Further, when the output light having a circular cross section is condensed on the workpiece by the processing condensing lens, a part of the output light irradiated to the work is reflected along the optical axis. The thermal lens effect is further increased, and the processing accuracy may be deteriorated.

  The temperature distribution of the processing condensing lens 80 of the laser apparatus 10 according to this embodiment that suppresses the thermal lens effect of the processing condensing lens will be described with reference to FIGS. In FIG. 7, the horizontal axis represents the distance in the direction orthogonal to the optical axis X0 with reference to the optical axis X0 of the processing condenser lens 80 (see FIG. 8), and the vertical axis represents the temperature of the processing condenser lens 80. Show. The center of the exit light PB having a cross-sectional donut shape is located on the optical axis X0 of the processing condensing lens 80. As shown in FIG. 6, 2X1 represents the inner diameter of the exit light PB having a cross-sectional donut shape. Denotes the outer diameter of the outgoing light PB having a donut shape in cross section, and 2X3 denotes the diameter of the processing condensing lens 80 as shown in FIG.

  In FIG. 7, the solid line L1 indicates the temperature distribution of the processing condensing lens 80 when the exit light PB having a cross-sectional donut shape passes through the processing condensing lens 80, and the broken line L2 indicates the output light having a circular cross section. The temperature distribution of the processing condensing lens 80 when passing through the processing condensing lens 80 of the embodiment is shown. In addition, as the emitted light having a circular cross section, the emitted light emitted from the optical fiber when three laser lights are incident on the center of the optical fiber is used.

  As can be seen from FIG. 7, when outgoing light having a circular cross section is transmitted through the processing condensing lens 80, the temperature is measured at the optical axis (the central portion of the processing condensing lens) X <b> 0 of the processing condensing lens 80. It becomes T0 and the temperature becomes the highest. This is because the heat received from the outgoing light having a circular cross section of the processing condensing lens 80 spreads radially around the optical axis X0.

  On the other hand, when the exit light PB having a donut cross section is transmitted through the processing condenser lens 80, the temperature is lowered at the optical axis X0 of the processing condenser lens 80, and the position is separated from the optical axis by ½ (X1 + X2). The temperature becomes T1 and the temperature becomes the highest. This is because the processing condensing lens 80 receives heat in a donut shape, and the heat diffuses in a direction away from the optical axis X0 of the processing condensing lens 80 and a direction toward the optical axis X0.

  In other words, when the exit light having a circular cross section passes through the processing condenser lens 80, the heat concentrates at one point on the optical axis X0 of the processing condenser lens 80, whereas the exit light having a donut cross section is formed. When the PB passes through the processing condenser lens 80, the heat received by the processing condenser lens 80 is distributed in a circumferential shape. Therefore, the temperature T1 becomes lower than the temperature T0. Therefore, since the thermal lens effect of the processing condenser lens 80 can be reduced, it is possible to suppress the shift of the focal position of the emitted light PB.

  According to this embodiment, since the outgoing light PB does not pass through the optical axis X0 of the processing condensing lens 80, the reflected light from the workpiece 18 toward the optical axis X0 of the processing condensing lens 80 is reduced. Thereby, it can suppress that the processing condensing lens 80 receives heat with the said reflected light, and the processing precision of the workpiece | work 18 deteriorates.

  The present invention is not limited to the above-described embodiment, and can be implemented in various forms. For example, the angle θ12 formed by the line segment A1 and the line segment A2, the angle θ13 formed by the line segment A1 and the line segment A3, and the angle θ23 formed by the line segment A2 and the line segment A3 may be arbitrarily set. The laser light output unit is not limited to a configuration that outputs fiber laser light. For example, a solid laser that outputs Nd: YAG laser light or the like may be used.

  The laser device of the present invention is not limited to the configuration in which the first to third fiber laser beams are incident on the condenser lens. For example, a configuration may be adopted in which only the first and second fiber laser beams are incident on the condenser lens without using the third fiber laser beam. In this case, the angle θ12 formed by the line segment A1 and the line segment A2 may be set to 180 °.

  Alternatively, the second and third fiber laser beams may be used without entering the first fiber laser beam at a position off the center of the condenser lens. In this case, the optical path adjustment unit of the above embodiment may be omitted, and the fiber laser beam output from the laser beam output unit may be directly incident on the condenser lens. Thereby, it is possible to cope with the case where the thermal lens effect is generated in the processing condensing lens with only one fiber laser beam. Further, a configuration may be adopted in which four or more fiber laser beams are incident on the incident end face of the synthetic fiber.

DESCRIPTION OF SYMBOLS 10 ... Laser apparatus 12 ... Laser beam output part 14 ... Transmission part 16 ... Synthesis | combination part 18 ... Work 20 ... Outgoing part 22 ... Control part 54 ... Synthetic fiber 61 ... Incidence end face 62 ... Condensing lens 64 ... Optical path adjustment part (optical path adjustment) Means) 72 ... Core 80 ... Condensing lens for processing L ... Perpendicular

Claims (4)

A laser beam output unit for outputting three laser beams;
A condensing lens that condenses the three laser beams output from the laser beam output unit;
An optical fiber having a core on which the three laser beams condensed by the condenser lens are incident;
Provided in an optical path between the laser beam output unit and the condenser lens, each of the three laser beams output from the laser beam output unit is located at a different position from the center of the condenser lens. Optical path adjusting means for adjusting the optical path of each laser beam to be incident , and
The laser beam output section as before Symbol condenser lens each said laser light condensed by is incident in a state of cross respect to the normal of the end face of the core, the condenser lens and the optical fiber is set and,
The optical path adjusting means is configured such that the three laser beams output from the laser beam output unit are spaced apart from each other and spaced apart at an equal angle in the circumferential direction, and the center of the condenser lens and each laser of the condenser lens Adjusting the optical paths of the three laser beams so that they are incident on the condenser lens so that they are equidistant from the incident position of the light;
A laser device characterized by that. The laser device according to claim 1, wherein
The optical fiber combines the three laser beams to emit one laser beam having a cross-sectional donut shape.
A laser device characterized by that. A laser beam adjusting method for condensing three laser beams output from a laser beam output unit onto a core of an optical fiber by a condensing lens,
A first step of entering each of three of the laser beam outputted from the laser beam output section by the optical path adjusting means to another position off the center of the condenser lens,
Performing the second step of entering each laser beam collected by the condenser lens in a state of being intersected with a perpendicular to the end face of the core ;
In the first step, the three laser beams output from the laser beam output unit are spaced apart from each other and spaced apart at an equal angle in the circumferential direction, and the center of the condenser lens and each laser of the condenser lens The three laser beams are incident on the condenser lens so as to be equidistant from the incident position of the light;
A method for adjusting a laser beam. In the adjustment method of the laser beam of Claim 3,
In the second step, the three laser beams are combined by the optical fiber to emit one laser beam having a cross-sectional donut shape.
A method for adjusting a laser beam.

Images