JP2001119101A - Laser device and laser beam machining device using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a laser device which can use relatively inexpensive general components, and at the same time, can realize a better transmission efficiency from a laser oscillation source to the outside and a laser beam machining device using the device. SOLUTION: A laser device makes anisotropic laser light emitted from a semiconductor laser made incident to one end side of an optical fiber, after condensing the laser light through a prescribed optical system. The laser light transmitted through the optical fiber is converted into an isotropic laser light. The optical fiber is a distributed refractive index type optical fiber.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a laser device for transmitting an output beam from a laser oscillation source to the outside via an optical fiber, and a laser processing device using the same.

[0002]

2. Description of the Related Art Conventionally, a laser device for transmitting an output beam from a semiconductor laser as a laser oscillation source to the outside has
It is well known that an optical fiber is used for a light guide path to the outside. In such a laser device, since the output beam from the laser oscillation source has anisotropy, usually, the output beam is isotropically converted and shaped via a predetermined optical system,
A configuration in which the light is incident on the optical fiber is employed, and the coupling efficiency between the laser oscillation source and the optical fiber is improved.

[0003] In this connection, FIG. 15 shows an example of a conventional semiconductor laser device, which is shown in OSA TOPS vol.
0 shows a semiconductor laser device disclosed on page 391 of Advanced Solid State Lasers. In this laser device 100, a laser beam output from a semiconductor laser array 101, which is a laser oscillation source, includes a micro lens 102,
Reflector 103 composed of a pair of micro-step mirrors
Then, the light is made incident on one end of the optical fiber 106 via the cylindrical lens 104 and the achromatic lens 105 and transmitted to the outside.

FIG. 16 is a perspective view of a semiconductor laser array 101 built in the laser device 100. In this semiconductor laser array 101, a plurality of emitters 101a
Are arranged in a line with the pn junction surface (not shown) flush. The output from each of the emitters 101a is about 1 W. For example, in order to obtain an output of several tens of W or more required for application to a laser processing apparatus, the output of the
A having a plurality of a's is used.

The laser beam output from the semiconductor laser array 101 generally emits light from the emitter 101a.
16 diverges relatively small along the direction in which are arranged (the X direction in FIG. 16, hereinafter referred to as the slow axis direction), while the direction perpendicular to the pn junction surface of the emitter 101 a (Y direction in FIG. 16).
(Hereinafter, referred to as the fast axis direction), it is known that there is a possibility that the divergence may be relatively large and the divergence may be non-uniform. As an index of the beam quality, for example, an M ² value indicating how many times the divergence angle of the laser beam is the theoretical limit is used. The individual emitters 10 shown in FIG.
Regarding the laser beam output from 1a, the beam quality in the fast axis direction (Y direction in the figure) is M ² = 1, and the beam quality in the slow axis direction (X direction in the figure) is:
M ² = 20. Incidentally, the better the beam quality M ² value is small, when compared with the beam of the same beam diameter, M ²
It is known that the smaller the value is, the smaller the divergence of the beam is. However, here, the beam divergence is smaller in the slow axis direction than in the fast axis direction despite the poor beam quality. This is because the smaller the beam diameter, the larger the divergence. As a result, the beam quality is poor, but the width of the emitter 101a is as large as about 100 μm in the slow axis direction.
The divergence in the direction of the fast axis, which is as small as about μm, is smaller. In any case, the beam emitted from such a semiconductor laser has a large anisotropy as described above. In the laser device 100, the beam quality is made uniform, and after the laser beam from the semiconductor laser array 101 is collimated by the microlens 102 disposed near the output side of the laser array 101, the laser beam is reflected by the reflecting unit 103 to 90 degrees. ° can be rotated.

[0006] As shown in FIG.
Reference numeral 3 denotes upper and lower micro step mirrors 103A and 103B which are arranged to face each other. The beam incident on the reflecting unit 103 from the horizontal direction is first reflected vertically upward on the reflecting surface 103b of the lower microstep mirror 103B. Next, the reflected beam is applied to the upper micro-step mirror 10.
The light is reflected by the reflecting surface 103a of 3A, and is emitted in the horizontal direction and in the direction perpendicular to the direction of incidence on the reflecting portion 103. In FIG. 17, the reflecting surfaces 103a and 103b are shown with hatching. Thus, the reflection unit 1
At 03, the beam is rotated 90 ° by two reflections on the upper and lower microstep mirrors 103A and 103B, and their vertical and parallel components are swapped.

[0007] By such a beam component exchange operation,
The output beam from the semiconductor laser array 102 having a difference in divergence between the vertical component and the parallel component can be made uniform for each component, and thereafter, the beam is output via the cylindrical lens 104 and the achromatic lens 105. Can be collected and coupled to the optical fiber 106. In this manner, in the semiconductor laser device 100, good coupling efficiency can be realized between the semiconductor laser array 101 and the optical fiber 106. As shown in FIG. 16, when a one-dimensional semiconductor laser array 101 in which 20 emitters 101a are arranged along the slow axis direction is used, a beam in the Y direction obtained through a microstep mirror 103 is used. The quality is M ² = 1 × 20 = 20
On the other hand, the beam quality in the X direction is M ² = 2
It remains at 0. As a result, the beam qualities in the X and Y directions are isotropically converted.

[0008]

In the conventional laser apparatus 101 as described above, the micro-step mirror 103, which is an optical system for beam shaping, is complicated in shape and expensive. Further, scattering loss occurs at the boundary surface of the microstep mirror 103, and the transmission efficiency of the beam output to the optical fiber having a diameter of 400 μm by the 1 cm bar of the one-dimensional semiconductor laser array is at most 70%.
And the laser device has a relatively low energy use efficiency.

Further, as a laser oscillation source built in the laser device 101, as shown in FIG.
A two-dimensional semiconductor laser array 110 in which a plurality of dimensionally arranged emitters 110a are stacked along the Y direction (fast axis direction) may be used. In this case, furthermore,
The configuration of the micro step mirror becomes complicated, which leads to a further increase in cost and scattering loss.

SUMMARY OF THE INVENTION The present invention has been made in view of the above technical problems, and it is possible to use relatively inexpensive and general components and to improve transmission efficiency from a laser oscillation source to the outside. An object of the present invention is to provide a laser device that can be realized and a laser processing device using the same.

[0011]

According to a first aspect of the present invention, there is provided a laser device for transmitting an output beam from a laser oscillation source to the outside via an optical fiber, comprising: a semiconductor laser having a plurality of emitters; Characterized by having an optical system for condensing laser light emitted from a semiconductor laser, and an optical fiber for receiving the laser light condensed by the optical system at one end side and transmitting the laser light to the outside It is.

Further, a second invention of the present application is the invention according to the first invention, wherein the optical fiber is a refractive index distribution type optical fiber.

In a third aspect of the present invention, in the second aspect, the beam waist near the incident end face of the graded index optical fiber in a direction perpendicular to and parallel to the active layer in the semiconductor laser. The diameters are expressed as φ _{0 · fast} and φ _{0 · slow in the} vertical direction and the parallel direction, respectively, and the full angle of the beam spread of the laser beam is 2θ _fast in the vertical direction and the parallel direction, respectively. 2
represented as theta _slow, further, the diameter of the core portion of the graded-index optical fiber is the phi _c, the refractive index of the center of the core portion is n _0, also further and the fiber core center When the difference between the refractive indices of the outer peripheral portion of the core is Δn, the beam diameters φ _{in · fast} and φ _{in · slow in the} vertical direction and the parallel direction when the light is incident on the refractive index distribution type optical fiber.
But, Is set.

Furthermore, a fourth invention of the present application is the semiconductor laser according to any one of the first to third inventions, wherein a plurality of emitters are one-dimensionally arranged in the semiconductor laser. It was done.

Furthermore, a fifth invention of the present application is the semiconductor laser according to any one of the first to third inventions, wherein a plurality of emitters are two-dimensionally arranged in the semiconductor laser. It was done.

Further, according to a sixth invention of the present application, in the fourth or fifth invention, a plurality of emitters in the semiconductor laser are grouped, and the optical system corresponds to each group of the emitters. And a plurality of optical fibers, and the laser light emitted from the semiconductor laser can be separated and transmitted.

Further, the seventh invention of the present application is provided with an optical system for condensing laser light supplied from a predetermined laser device, and performing laser processing using the condensed laser light. A laser processing apparatus provided with the laser apparatus according to any one of the first to sixth aspects.

[0018]

Embodiments of the present invention will be described below with reference to the accompanying drawings. Embodiment 1 FIG. FIG. 1 schematically shows a configuration of a laser processing apparatus according to Embodiment 1 of the present invention. The laser processing apparatus 1 includes a laser apparatus 10 for transmitting a laser beam from a laser oscillation source (see FIG. 2) to the outside via an optical fiber 2.
And a processing head 3 for condensing the laser beam transmitted via the optical fiber 2 and irradiating the laser beam to the workpiece 9. The processing head 3 includes a collimating lens 4 for beam aiming and a processing lens 5 arranged so as to have the same optical axis, and emits laser light condensed by these lenses toward the workpiece 9. I do. In addition, the processing head 3 is provided with a nozzle 6 for blowing an assist gas sent from an assist gas pipe 8 to the workpiece 9 during operation. In the laser processing apparatus 1 having such a configuration, the processing head 3 can be arbitrarily driven by a predetermined driving member (not shown) above the workpiece 9 held on the worktable. At the desired position,
The laser beam generated by the laser device 10 is supplied to the processing head 3 through the optical fiber 2 and is emitted from the processing head 3 to the workpiece 9, whereby the workpiece 9 is processed at a predetermined position.

FIG. 2 is a perspective view schematically showing the configuration of the laser device 10 provided in the laser processing device 1. As shown in FIG.
The laser device 10 includes a semiconductor laser array 11 having a plurality of semiconductor laser light emitting units (hereinafter, referred to as emitters) 12 arranged one-dimensionally on a laser light emitting surface side, and a laser output from the semiconductor laser array 11. It has an optical system 13 for condensing light, and an optical fiber 2 for receiving the light condensed by the optical system 13 at one end thereof.

The emitter 12 in the semiconductor laser array 11 forms a laser output port in each active layer 99. The optical system 13 is composed of substantially semi-cylindrical lenses 13A and 13B and a convex lens 13C. The optical system 13 is arranged so as to have the same optical axis 14 in the above order from the side closer to the semiconductor laser array 11. Have been.
Further, one end of the optical fiber 2 is positioned on the optical axis 14 of these three lenses.

In the first embodiment, an optical fiber of a refractive index distribution type is used as the optical fiber 2 serving as a light guide path to the processing head 3 based on the waveguide characteristic with relatively little deterioration in beam quality. I did it. However, the present invention is not limited to this. For example, a step index type optical fiber whose refractive index is constant with respect to the radius of the core may be used. In addition, as the optical system 13, an inexpensive one that is generally commercially available can be used.

The operation of transmitting laser light by the laser device 10 having the above configuration will be described. First, when laser light is output from the plurality of emitters 12 in the semiconductor laser array 11, almost all of the
Incident on. As will be described in detail later, at this time, the laser light L ₀ output from the emitter 12 has anisotropy, and propagates with different divergence in a direction perpendicular to the active layer 99 and in a direction parallel thereto. The light enters the system 13. Thereafter, the laser light is applied to the lenses 13A and 13B of the optical system 13.
And 13C, and is emitted from the optical system 13. As a result, the laser light L ₁ enters from one end of the optical fiber 2 in a state having anisotropy. The laser light L ₁ having anisotropy is converted into laser light L ₂ having isotropic quality by passing through the optical fiber 2. The operation of transmitting the laser light is as follows.
As shown in FIG. 3, the same applies to the case where consideration is given for each emitter.

Next, the beam divergence characteristics of the emitter 12 in the semiconductor laser array 11 will be described with reference to a single emitter. In this description, it is assumed that a refractive index distribution type optical fiber is used as the optical fiber 2. As described above, the laser light output from the emitter 12 has anisotropy, and is incident on the optical system 13 while propagating with different divergence in directions perpendicular and parallel to the active layer 99, respectively. . FIG. 4 and FIG. 5 are diagrams showing the state of beam divergence in the vertical direction and the parallel direction of the active layer 99, respectively. As can be seen from these figures, the beam divergence due to the emitter 12 is typically relatively large in the direction perpendicular to the active layer 99, while relatively small in the parallel direction. In the following, the directions of the former and the latter, respectively,
They are called fast axis direction and slow axis direction.

The laser light L ₁ output from the emitter 12 at different divergence in the fast axis direction and the slow axis direction is
As shown in FIGS. 4 and 5, the light is condensed through lenses 13A, 13B, and 13C in the optical system 13 and is incident on one end of the optical fiber 2. FIG. 6 shows the shape of the incident laser light on one end surface of the optical fiber 2. As can be seen from Figure 6, the diameter of the core part 2a of the refractive index spectral optical fiber 2 is phi _c. At this time, the diameters φ _{in · fast} and φ _{in · slow} of the incident laser light L ₁ in the fast axis direction and the slow axis direction are respectively Within the range represented by However, here, φ _{0 · fast}
And φ _{0 · slow} are the beam waist diameters near the incident end face of the gradient index optical fiber in the fast axis direction and the slow axis direction, respectively, and 2θ _fast and 2θ _slow are in the fast axis direction and the slow axis direction, respectively. The beam spread of the laser beam is full angle. Further, n ₀ is the refractive index at the center of the core 2a, and Δn is the center of the core 2a and the outer periphery 2b of the core.
(See FIG. 6). FIG. 7 shows a general refractive index distribution of the gradient index optical fiber 2.
Shows the relationship between the distance from the center and the refractive index.

As shown in FIG. 6, when a laser beam 4 having an anisotropic beam shape is incident on one end side of the gradient index optical fiber 2 under the above-mentioned range, the gradient index optical fiber 2 the laser beam L ₂ emitted from the second end side, as shown in FIG. 8, a laser beam of diameter phi _out with isotropic. At this time, if the quality in the fast axis direction before entering the gradient index optical fiber 2 is M ² _fast and the quality in the slow axis direction is M ² _slow , the beam emitted from the gradient index optical fiber 7 is assumed. quality M ² _out of is as shown in FIG. As can be seen from FIG. 9, in the range incident beam diameter of 0.5φ _s ~2.0φ _s to the gradient index optical fiber 2, The beam quality M ² _out in the range is obtained.

In the above description, the transmission operation for making the laser light having anisotropy isotropic via the optical fiber 2 has been described for the single emitter 12. However, as shown in FIG. When a plurality of emitters 12 arranged one-dimensionally in 11 are considered as one group, the transmission operation is the same as the transmission operation of the single emitter 12 described above, and the same effect is obtained.

As described above, in the laser device 10, the laser beam L ₀ having anisotropy is condensed and made incident on the optical fiber 2, and the laser beam is isotropic via the optical fiber 2. With such conversion, good laser light transmission efficiency between the semiconductor laser array 11 and the outside can be realized. In an experiment conducted by the inventor of the present application, when the above-described laser device 10 was used, a transmission efficiency of 90% or more could always be obtained. Further, in the laser device 10, a relatively inexpensive device that is generally commercially available can be used as the optical system 13, so that manufacturing costs can be reduced.

In the laser processing apparatus 1 shown in FIG. 1, laser light having anisotropy emitted from the semiconductor laser array 11 is condensed and incident on the optical fiber 2 in the laser apparatus 10, By supplying the laser beam to the processing head 3 after converting the data to have isotropic properties, good transmission efficiency between the semiconductor laser array 11 and the processing head 3 can be realized. As a result, the energy use efficiency of the laser processing device 1 can be significantly improved. In the first embodiment, as described above, the processing head 5 is provided with the processing lens 5 for condensing the laser beam and directing the laser light to the workpiece 9. By further converting and shaping the beam converted so as to have the above by the processing lens 5, more isotropic laser light can be obtained. As a result, high-quality laser processing can be performed at high speed.

Hereinafter, another embodiment of the present invention will be described.
This will be described with reference to the accompanying drawings. In the following description, the same components as those in the first embodiment are denoted by the same reference numerals, and further description is omitted. Embodiment 2 FIG. FIG. 10 is a perspective view showing a configuration of a laser device according to Embodiment 2 of the present invention. The basic configuration of this laser device 20 is the same as that of the above-described first embodiment.
In FIG. 1, a plurality of emitters 22 are two-dimensionally arranged by, for example, one-dimensionally arranged emitters as shown in FIG. In this case, as in the case of the first embodiment, the laser light L ₁₀ emitted from the semiconductor laser array 21 and the laser light L
₁₁ has anisotropy, the laser light L ₁₂ having isotropic through the optical fiber 2 is obtained. Thus, when this laser device 20 is employed in, for example, the laser processing device 1 as shown in FIG.
Good transmission efficiency can be realized between the head and the processing head 3.

Embodiment 3 FIG. 11 is a perspective view showing a configuration of a laser device according to Embodiment 3 of the present invention. In this laser device 30, a plurality of emitters 32 arranged one-dimensionally in a semiconductor laser array 31 are divided into three sets (in this embodiment, each including three emitters). , A plurality of optical fibers 2 are provided. Also, the optical system 33
Thus, each lens 33A, 33B and 33C is designed to be compatible with each set of the emitters 32.

The transmission of laser light by the laser device 30 is described.
The sending operation is performed for each set of the emitters 32 as described above.
First, a semiconductor laser is used.
Anisotropy from each set of emitters 32 in the array 31
Having laser light L₃₀Are emitted, the optical system
The corresponding lenses 33A, 33B and 33C at 33
And is incident on one end of each optical fiber 2.
It is. Incident laser light L ₃₁Respectively connect the optical fiber 2
Laser beam L having isotropic properties₃₂Is converted to
The light is emitted from the other end of the fiber 2 to the outside. Emitted
Number of laser light L ₃₂Are available separately from each other.
Thus, the ratio emitted from the semiconductor laser array 31 is
Separates a laser beam with a relatively wide width and
By transforming it to be isotropic via
Laser light transmission from the semiconductor laser array 31 to the outside
The efficiency can be maintained sufficiently well.

Embodiment 4 FIG. FIG. 12 is a perspective view showing a configuration of a laser device according to Embodiment 4 of the present invention. The laser device 40 has the same basic configuration as that of the above-described third embodiment. However, in this fourth embodiment, by bundling a plurality of optical fibers 2 on the laser light emission side,
The laser light L ₄₂ emitted is to be used as a single beam. In the laser device 40, similarly to the above-described third embodiment, the efficiency of transmitting the laser light from the semiconductor laser array 31 to the outside can be sufficiently maintained, and further, the emitted laser light L
_The laser light having a relatively high intensity can be obtained by combining the ₄₂ with one.

Embodiment 5 FIG. FIG. 13 is a perspective view showing a configuration of a laser device according to Embodiment 5 of the present invention. The basic configuration of this laser device 50 is the same as that of the above-described third embodiment. However, in the fifth embodiment, in the semiconductor laser array 51, a plurality of emitters 52 are arranged, for example, as shown in FIG. The two-dimensionally arranged emitters are further stacked in a plurality of layers to form a two-dimensionally arranged emitter.

The transmission operation by the laser device 50 is the same as that in the third embodiment described above. When the laser beam L ₅₀ having anisotropy is emitted from each set of the emitters 52, the optical system At 53, the light is condensed by the corresponding lenses 53A, 53B and 53C, and made incident on one end of each optical fiber 2. The incident laser light _L51 is
Respectively through the optical fiber 2 is converted into laser light L ₅₂ having isotropic, being emitted from the other end of the optical fiber 2 to the outside. A plurality of laser light L ₅₂ emitted is available separately from each other. By separating the laser light having a relatively wide width and height emitted from the semiconductor laser array 51 and converting the laser light to have isotropic properties through the plurality of optical fibers 2, the laser light is separated from the semiconductor laser array 51. Laser light transmission efficiency can be sufficiently maintained.

Embodiment 6 FIG. FIG. 14 is a perspective view showing a configuration of a laser device according to Embodiment 6 of the present invention. The laser device 60 has the same basic configuration as that of the above-described fifth embodiment. However, in the fifth embodiment, a plurality of optical fibers 2 are bundled on the laser light emission side,
The laser light L ₆₂ emitted is to be used as a single beam. In the laser device 60, similarly to the case of the above-described fifth embodiment, the laser light transmission efficiency from the semiconductor laser array 51 to the outside can be maintained sufficiently high, and further, the emitted laser light L
By combining ₆₂ in a single unit, a laser beam having relatively high intensity can be obtained.

The present invention is not limited to the illustrated embodiment, and it goes without saying that various improvements and design changes can be made without departing from the spirit of the present invention.

[0037]

According to the first aspect of the present invention, a semiconductor laser having a plurality of emitters, an optical system for condensing laser light emitted from the semiconductor laser, and a laser beam condensed by the optical system And an optical fiber for receiving the laser light at one end and transmitting the laser light to the outside. The laser light having anisotropy is condensed and incident on the optical fiber, and the laser light is transmitted through the optical fiber. Is converted to have isotropic properties, so that good laser light transmission efficiency between the semiconductor laser and the outside can be realized. In addition, as the optical system, a relatively inexpensive optical system that is generally commercially available can be used, so that manufacturing costs can be reduced.

Further, according to the invention of claim 2 of the present application, since a refractive index distribution type optical fiber is used as the optical fiber, deterioration of beam quality can be suppressed.

Further, according to the invention of claim 3 of the present application,
Direction perpendicular and parallel to the active layer in the semiconductor laser
Near the entrance end face of the graded index optical fiber at
The waist diameter in the vertical and parallel directions
And, respectively, φ_{0 ・ fast}, Φ _{0 ・ slow}And
The full angle of the beam spread of the laser beam is
For each direction, 2θ_fast, 2θ_slowExpressed
And the diameter of the core of the gradient index optical fiber.
Is φ_cAnd the refractive index at the center of the core portion is n₀And
Further, the refractive indices of the center of the fiber core and the outer periphery of the core are determined.
When the difference is Δn, the refractive index distribution type optical fiber
Regarding the above vertical and parallel directions when
Beam diameter φ_{in ・ fast}, Φ_{in ・ slow}But, The anisotropy emitted from the semiconductor laser
Laser light with a refractive index distribution type optical fiber
Efficient conversion to isotropic laser light
You. As a result, a better connection between the semiconductor laser and the outside is obtained.
Laser light transmission efficiency can be realized.

Further, according to the invention of claim 4 of the present application, in the semiconductor laser, a plurality of emitters are arranged one-dimensionally, so that the output from a larger semiconductor laser can be used.

Further, according to the invention of claim 5 of the present application, in the semiconductor laser, a plurality of emitters are two-dimensionally arranged, so that a larger output from the semiconductor laser can be used. .

Further, according to the invention of claim 6 of the present application, a plurality of emitters in the semiconductor laser are grouped, and a plurality of optical systems and optical fibers are provided corresponding to each group of the emitters. By separating the laser light emitted from the semiconductor laser and converting each laser light to have isotropic properties through a plurality of optical fibers, the efficiency of laser light transmission from the semiconductor laser to the outside is improved. Can be maintained sufficiently satisfactorily.

Further, according to the invention of claim 7 of the present application, an optical system for condensing laser light supplied from a predetermined laser device is provided, and laser processing is performed using the condensed laser light. In the laser processing apparatus configured as described above,
The laser device according to any one of claims 1 to 6 of the present application is provided, and in the laser device, laser light having anisotropy emitted from a semiconductor laser is condensed and incident on an optical fiber. Then, after being converted to have isotropy via an optical fiber and then supplied to the processing head, good transmission efficiency can be realized between the semiconductor laser and the processing head. As a result, the energy utilization efficiency of the laser processing device can be significantly improved.
Further, according to the present invention, the processing head is provided with an optical system for condensing the laser beam, and the beam converted to have isotropic properties via the optical fiber is further converted by the optical system. By shaping, a more isotropic laser beam can be obtained. As a result, high-quality laser processing can be performed at high speed.

[Brief description of the drawings]

FIG. 1 is a diagram showing a configuration of a semiconductor laser processing apparatus according to a first embodiment of the present invention.

FIG. 2 is a diagram schematically showing a laser device incorporated in the semiconductor laser processing device.

FIG. 3 is a diagram showing a mode of beam transmission with respect to a single emitter of a semiconductor laser in the laser device.

FIG. 4 is a diagram showing a mode of beam propagation in a fast axis direction in an output beam from the semiconductor laser.

FIG. 5 is a diagram illustrating a mode of beam propagation in a slow axis direction in an output beam from the semiconductor laser.

FIG. 6 is a perspective view showing a mode of a beam at an incident end face of the optical fiber.

FIG. 7 is a graph showing a refractive index distribution of the optical fiber.

FIG. 8 is an enlarged view showing a mode of a beam at an emission end face of the optical fiber.

FIG. 9 is a graph showing a relative relationship between a diameter of an incident beam of the optical fiber and a beam quality after exit.

FIG. 10 is a diagram schematically showing a semiconductor laser device according to a second embodiment of the present invention.

FIG. 11 schematically shows a semiconductor laser device according to a third embodiment of the present invention.

FIG. 12 is a diagram schematically showing a semiconductor laser device according to a fourth embodiment of the present invention.

FIG. 13 schematically shows a semiconductor laser device according to a fifth embodiment of the present invention.

FIG. 14 schematically shows a semiconductor laser device according to a sixth embodiment of the present invention.

FIG. 15 is a diagram showing a mode of beam transmission between a semiconductor laser array and an optical fiber in a conventional laser device.

FIG. 16 is a perspective view showing a one-dimensional semiconductor laser array used in a conventional laser device.

FIG. 17 is a diagram showing a mode of light reflection in a micro step mirror incorporated in a conventional laser device.

FIG. 18 is a perspective view showing a two-dimensional semiconductor laser array used in a conventional laser device.

[Explanation of symbols]

1 laser processing device, 2 optical fiber, 2a core,
2b core outer periphery, 3 processing head, 11 semiconductor laser array, 12 emitter, 13 optical system, 99 active layer,
L ₁ emitted laser light, L ₂ incident laser light

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Tetsuo Kojima 2-3-2 Marunouchi, Chiyoda-ku, Tokyo Inside Mitsui Electric Co., Ltd. (72) Inventor Koji Yasui 2-3-2 Marunouchi, Chiyoda-ku, Tokyo 3 Rishi Electric Co., Ltd. F-term (reference) 2H037 AA04 BA04 CA16 CA17 DA03 DA04 DA05 4E068 CE08 CK01 5F073 AB04 AB27 AB28 BA09 EA24

Claims (7)

[Claims] 1. A semiconductor laser having a plurality of emitters, an optical system for condensing laser light emitted from the semiconductor laser, and a laser light condensed by the optical system received at one end side to the outside. A laser device having an optical fiber for transmission. 2. The laser device according to claim 1, wherein the optical fiber is a refractive index distribution type optical fiber. 3. A beam waist diameter near an incident end face of the gradient index optical fiber in a direction perpendicular to and parallel to an active layer in the semiconductor laser is φ _{0 in the} vertical direction and the parallel direction, respectively. _{· fast,} represented as phi _{0 · slow,} the beam spread em of the laser beam, for the vertical and parallel directions, respectively, 2 [Theta] _fast,
2θ _slow , the diameter of the core of the gradient index optical fiber is φ _c , the refractive index at the center of the core is n ₀ , and the center of the fiber core is When the difference in the refractive index of the core outer peripheral portion is Δn, the beam diameter φ _{in ·
fast} , φ _{in ・ slow} 3. The laser device according to claim 2, wherein: 4. The laser device according to claim 1, wherein in the semiconductor laser, a plurality of emitters are arranged one-dimensionally. 5. The laser device according to claim 1, wherein in the semiconductor laser, a plurality of emitters are two-dimensionally arranged. 6. A plurality of emitters in the semiconductor laser are grouped, and a plurality of optical systems and optical fibers are provided corresponding to each of the emitters. Laser light emitted from the semiconductor laser is provided. The laser device according to claim 4, wherein the laser device can be transmitted separately. 7. A laser processing apparatus, comprising: an optical system for condensing laser light supplied from a predetermined laser device, wherein laser processing is performed using the condensed laser light. A laser processing apparatus comprising the laser apparatus according to claim 1.