JP2001127361A - Solid-laser generating apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain easily a laser beam of a large output power and make its beam quality adjustable, by combining a small-sized laser oscillator with a small-sized laser amplifier. SOLUTION: A solid-laser generating apparatus has a laser oscillator 21 and a laser amplifier 23. In the laser oscillator 21 on an oscillator-side base 22, a required number of oscillating portions 4 each of which has a solid laser rod 2 and two excitation lamps 3 are disposed along an optical path S, and resonance mirrors 6, 7 are so disposed along the optical path S of the solid laser rod 2 as to interpose the oscillating portions 4 between them, and further, an incident optical system 9 is disposed closely to the resonance mirror 7 on a laser deriving side. In the laser amplifier 23 on an amplifier-side base 24, a required number of oscillating portions 13 each of which has another solid laser rod 2 and other two excitation lamps 3 are disposed along another optical path S, and a collimator 25 and an incident optical system 15 are so disposed respectively on one- and the other-side of the base 24 as to interpose between them the oscillating portions 13 present on the optical path S of the solid laser rod 2. Moreover, the incident optical system 9 of the laser oscillator 21 and the collimator 25 of the laser amplifier 23 are connected by a coupling optical fiber 26.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a solid-state laser generator which is provided with a plurality of solid rods of a laser medium and is effective in increasing laser output.

[0002]

2. Description of the Related Art As shown in FIG. 3, a general solid-state laser generator includes, in a casing 1, a solid rod 2 which is a laser medium such as an Nd: YAG laser rod and the like. An oscillating unit 4 provided with an excitation lamp 3 which is a rod-shaped body such as a xenon lamp to be arranged is fixed on a base plate 5.

[0003] The solid rod 2
Resonator mirrors 6 and 7 are provided facing each other on the optical path S (axial line) and at positions sandwiching the oscillation section 4 from both sides.
Further, an incident optical system 9 having a convex lens 8 and the like is arranged at an outer position close to the resonator mirror 7 on the laser extraction side, and emits the laser light focused by the convex lens 8 to the output optical fiber 10. It has become.

In order to oscillate laser light by the solid-state laser generator shown in FIG. 3, excitation light emitted from an excitation lamp 3 is incident on a solid rod 2 directly or via a reflection surface (not shown) of a casing 1. Upon receiving the excitation light, ions such as neodymium present in the laser medium of the solid rod 2 emit light of a specific wavelength, and the light of the specific wavelength is emitted in the axial direction of the solid rod 2 and is applied to the resonator mirrors 6 and 7. Be guided.

The light of the specific wavelength is repeatedly reflected between the two resonator mirrors 6 and 7, so that light is incident on the solid rod 2 and light is emitted from the solid rod 2 repeatedly. The output is increased by the ions in 2 resonating so as to newly emit light of a specific wavelength, and the laser light having the increased output is extracted outside from the resonator mirror 7 on the laser extraction side. The laser beam extracted from the resonator mirror 7 is adjusted in beam diameter by the convex lens 8 of the incident optical system 9 and the like.
The laser beam is incident on the laser beam 0 and supplied to a laser utilizing device (not shown).

On the other hand, in recent years, high-power laser light has been required. In order to generate such a high output laser beam, as shown in FIG. 4, a large number of laser beams are arranged between the resonator mirrors 6 and 7 on the base plate 5 so as to be located on the optical path S of the solid rod 2. This can be achieved by arranging the oscillation units 4 in series. On the other hand, at this time, by controlling the lamp current of the excitation lamp 3, the output of the laser beam can be increased with a certain width.

As shown in FIG. 4, in a solid-state laser oscillator having a large number of oscillators 4, light of a specific wavelength which is excited by excitation light of an excitation lamp 3 and emitted from a solid rod 2 is connected in series. Are incident on a plurality of other solid rods 2 or resonator mirrors 6 and 7 arranged in
Between 7, the light incident on the plurality of solid rods 2 and the light emission from the plurality of solid rods 2 are repeated, and the output of the laser light is greatly increased by increasing the number of repetitions. be able to. The laser light whose output has been increased is emitted from the resonator mirror 7 on the laser extraction side to the output optical fiber 10 via the incident optical system 9.

However, the solid-state laser generator for oscillating high-power laser light as shown in FIG. 4 has a large length in the installation direction of the oscillation section 4 because a large number of oscillation sections 4 are arranged in series. It will be long. For example, in order to obtain a laser beam having a large output such as 10 kW, it is necessary to arrange ten or more solid rods 2, and therefore, the length of the solid-state laser generator is about 10 meters. .

As described above, when the length of the solid-state laser generator is increased, a large installation space is required and the optical path S is increased.
The optical axis is likely to be out of order, and if the optical axis is out of order, there is a problem that it takes a lot of time to redo the adjustment. Further, in order to prevent the optical axis from being deviated as described above, it is necessary to greatly increase the rigidity of the base plate 5, which causes a problem that the cost of the apparatus is increased.

On the other hand, as means for solving the above-mentioned problem, a solid-state laser generator as shown in FIG. 5 has also been proposed.

The solid-state laser generator shown in FIG. 5 has a configuration in which a laser oscillator 11 and a laser amplifier 12 are provided on a base plate 5.

That is, the required number of oscillators 4 (three in FIG. 5)
The base plate 5 is provided with a laser oscillator 11 including resonator mirrors 6 and 7 disposed so as to sandwich the oscillation unit 4 and an incident optical system 9 disposed close to the resonator mirror 7 on the laser output side. In addition, a required number of oscillating units 13 (three in FIG. 5) having the same configuration as the oscillating unit 4 and the oscillating unit 1 on the optical path S of the solid rod 2 of the oscillating unit 13
3 and a collimator 14 arranged on one side of
Optical system 1 having a convex lens 8 disposed on the other side of
5 is disposed on the base plate 5 in parallel with the laser oscillator 11. 10
Is an output optical fiber connected to the incident optical system 15.

Further, two reflection mirrors 16 and 17 for guiding laser light emitted from the incident optical system 9 of the laser oscillator 11 to the collimator 14 of the laser amplifier 12 are arranged on the base plate 5. The collimator 14
Is the reflection mirror 1 from the incident optical system 9 of the laser amplifier 12.
The convex lens 18 for converting the laser light introduced through the lenses 6 and 17 into parallel light, the convex lens 19 for narrowing the parallel light by the convex lens 18, and the light narrowed down by the convex lens 19 are again converted to parallel light, and the oscillation unit 13 And a concave lens 20 which is incident on the solid rod 2.

In the solid-state laser generator shown in FIG. 5, the laser oscillator 11 is provided with three oscillating units 4 and the laser amplifier 12 is also provided with three oscillating units 13, so that the laser oscillator 11 is provided. And the laser amplifier 12 can increase the laser output.

[0015]

However, in the solid-state laser generator shown in FIG.
If the output of laser light is to be further increased by increasing the number of oscillating units 4 and 13 provided in the laser amplifier 12, the overall configuration of the solid-state laser generator becomes large. In addition, when the solid-state laser generator becomes large, a large installation space is required,
The optical axis of the optical path S is likely to be out of order due to the reflection mirrors 16 and 17, and if the out-of-axis occurs, there is a problem that it takes a lot of time to redo the adjustment. Also, in order to prevent the optical axis from being misaligned as described above,
It is necessary to greatly increase the rigidity of the base plate 5,
Constructing such a large-sized base plate 5 with high rigidity causes a problem that the cost of the apparatus is greatly increased.

The present invention has been made in view of the above-mentioned circumstances, and a solid-state laser capable of easily obtaining high-power laser light and adjusting the beam quality by a combination of a small laser oscillator and a laser amplifier. It is intended to provide a laser generator.

[0017]

According to the present invention, there is provided a solid-state laser generator comprising: a solid-state laser having a solid-state rod of a laser medium and an excitation lamp corresponding to the solid-type rod in a casing; The required number of resonator mirrors are arranged on the optical path of the solid rod, and the resonator mirrors are arranged so as to sandwich the oscillation part on the optical path of the solid rod, and the incident optical system is arranged so as to approach the resonator mirror on the laser extraction side A laser oscillator, and an amplifier side base, a solid rod of a laser medium and an excitation lamp corresponding to the solid rod are provided with a required number of oscillating units provided in a casing on an optical path of the solid rod, In addition, a collimator is arranged on one side of the solid rod on the optical path with the oscillating portion therebetween, and the incident optical system connected to the output optical fiber is arranged on the other side of the oscillating portion with the incident optical system. A amplifier is for the incident optical system of the laser oscillator, characterized in that connected between the collimator of the laser amplifier at the connecting optical fiber.

In the above means, a plurality of laser amplifiers may be provided, and the laser amplifiers may be connected to each other by a connecting optical fiber. Alternatively, a graded index optical fiber may be used as the connecting optical fiber. Further, instead of the collimator, an autocollimator capable of adjusting the spot diameter of the beam incident on the solid rod may be provided.

The above means operates as follows.

The laser oscillator provided on the oscillator-side base and the laser amplifier provided on the amplifier-side base are separately provided, and the laser oscillator and the laser amplifier are connected by a connection optical fiber. In addition, even if the configuration of the laser amplifier is small, it is possible to easily generate high-power laser light by increasing the number of laser amplifiers. Further, even in an existing laser generator, it is possible to easily achieve an increase in laser output by adding the above laser amplifier.

In addition, since the laser oscillator and the laser amplifier can be miniaturized, handling becomes easy, and the laser oscillator and the laser amplifier can be easily installed even in a narrow installation space. Maintenance is easy and the reliability of the device can be improved.

By using a graded index optical fiber as the coupling optical fiber, the density of laser light guided from the laser oscillator to the laser amplifier can be increased.
High quality laser light can be obtained.

Further, since the laser light from the laser oscillator is introduced into the autocollimator of the laser amplifier, the beam diameter of the laser light incident on the solid rod of the laser amplifier is adjusted by adjusting the autocollimator. Therefore, the quality of the laser light amplified by the laser amplifier can be improved.

[0024]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 shows an example of an embodiment of a solid-state laser generator according to the present invention. In the figure, the parts denoted by the same reference numerals as those in FIGS.

In FIG. 1, reference numeral 21 denotes a laser oscillator. In the laser oscillator 21, three oscillating units 4 each containing a solid rod 2 and an excitation lamp 3 in a casing 1 are connected in series to an oscillator-side base 22. Are located in Further, on the optical path S of the solid rod 2, resonator mirrors 6, 7 are disposed opposite to each other at positions sandwiching the three oscillation sections 4. Is provided with an incident optical system 9.

In FIG. 1, reference numeral 23 denotes a laser amplifier. In the laser amplifier 23, three oscillating units 13 each containing a solid rod 2 and an excitation lamp 3 in a casing 1 are connected in series to an amplifier-side base 24. Are located in Further, a collimator 25 is disposed on one side of the solid rod 2 sandwiching the oscillation unit 13, and an incident optical system 15 connected to the output optical fiber 10 is arranged on the other side sandwiching the oscillation unit 13. Is arranged.

The above-mentioned incident optical system 9 of the laser oscillator 21
And a collimator 25 of the laser amplifier 23 are connected by a connection optical fiber 26. The output optical fiber 10 connected to the incident optical system 15 of the laser amplifier 23 is connected to a processing head 28 for processing a processing load 27 and the like.

Although FIG. 1 shows an example in which only one laser amplifier 23 is provided, a plurality of laser amplifiers 23 are provided, and the incident optical system 15 of the laser amplifier 23 is connected to the collimator 25 of another laser amplifier 23. The connection can be made via the connection optical fiber 26.

In the above, the connecting optical fiber 26
A graded index optical fiber 26A can be used. The graded index type optical fiber 26A is a high quality laser having a silica core containing titanium, germanium, etc., having a high refractive index on the center side and an increased density with respect to incident laser light. It can output light.

Further, instead of the collimator 25 provided in the laser amplifier 23, an autocollimator 2 capable of adjusting the spot diameter of the beam incident on the solid rod 2 is used.
5A can be used.

As shown in FIGS. 1 and 2, the autocollimator 25A takes in the laser light introduced from the incident optical system 9 of the laser oscillator 21 by the coupling optical fiber 26 or the graded index optical fiber 26A. A convex lens 18 for making parallel light, and a convex lens 18
And a concave lens 20 for converting the light converged by the convex lens 19 into parallel light again and incident on the solid rod 2 of the oscillating unit 13.
The concave lens 20 is an adjustable concave lens 20A in which the mutual distance L with the convex lens 19 can be adjusted.
Thereby, the beam diameter of the laser beam incident on the solid rod can be adjusted.

The operation of the above embodiment will be described below.

In the laser oscillator 21 shown in FIG. 1, light of a specific wavelength excited by the excitation light of the excitation lamp 3 and emitted from the solid rod 2 is applied to another plurality of solid rods 2 or resonators arranged in series. The light enters the mirrors 6 and 7, and between the two resonator mirrors 6 and 7, the light incidence on the plurality of solid rods 2 and the emission of light from the plurality of solid rods 2 are repeated. The output is increased by increasing the number of times, and the laser light having the increased output is output to the outside from the resonator mirror 7 on the laser extraction side.
The light enters the collimator 25 of the laser amplifier 23 from the incidence optical system 9 via the connection optical fiber 26.

The laser light incident on the collimator 25 is
The output is increased by being incident on the solid rods 2 of the oscillation unit 13 provided in the laser amplifier 23 and excited by the excitation light of the excitation lamp 3, and further output by being incident on the other solid rods 2. After the increasing action is repeated a plurality of times, the laser light whose output is increased is emitted to the incident optical system 15 and guided to the processing head 28 via the output optical fiber 10, and is used for processing the processing load 27. used.

As shown in FIG. 1, the oscillator-side base 22
Is provided separately from the laser oscillator 21 provided on the amplifier-side base 24, and the laser oscillator 21 and the laser amplifier 23 are connected by the connecting optical fiber 26. Even if the device 21 and the laser amplifier 23 are small devices, a large output laser beam can be easily generated by increasing the number of the laser amplifiers 23. Therefore, even in existing equipment, it is possible to easily achieve an increase in laser output by adding the laser amplifier 23.

Further, as described above, the laser oscillator 21
Since the laser amplifier 23 can have a small configuration, it is easy to handle, and can be easily installed in a free layout even in a narrow installation space. Performance can be easily maintained and the reliability of the device can be improved.

In the above description, the connecting optical fiber 26
When the graded index optical fiber 26A is used, the density of the laser light from the incident optical system 9 of the laser oscillator 21 is increased by the graded index optical fiber 26A with respect to the incident laser light, so that the quality is improved. The laser beam can enter the laser amplifier 23 as the laser beam. Therefore, the quality of the laser light amplified by the laser amplifier 23 can be improved.

Further, the connecting optical fiber 26 or the graded index optical fiber 2
Since the laser light emitted to the laser collimator 6A is introduced into the autocollimator 25A of the laser amplifier 23, the adjustable concave lens 20 of the autocollimator 25A shown in FIG.
By adjusting the position of A so that the mutual distance L with the convex lens 19 changes, the beam diameter of the laser light incident on the solid rod 2 of the oscillation unit 13 can be adjusted. Thereby, the quality of the laser light amplified by the laser amplifier 23 can be improved. Further, at this time, the output of the laser beam by the laser amplifier 23 can be increased by adjusting the lamp current of the excitation lamp 3, but also by adjusting the position of the adjustable concave lens 20A of the autocollimator 25A. There is a possibility that the output of the laser light emitted from the laser amplifier 23 can be adjusted.

The solid-state laser generator of the present invention is not limited to the above-described embodiment, but is not limited to the number of oscillation units provided in the laser oscillator and the laser amplifier. Not limited,
In addition, it goes without saying that various changes can be made without departing from the spirit of the present invention.

[0041]

According to the solid-state laser generator of the present invention,
Various excellent effects as described below can be obtained.

The laser oscillator provided on the oscillator-side base and the laser amplifier provided on the amplifier-side base are separately provided, and the laser oscillator and the laser amplifier are connected by a connection optical fiber. Further, even if the configuration of the laser amplifier is small, there is an effect that a large output laser beam can be easily generated by increasing the number of laser amplifiers. Further, even in an existing laser generator, there is an effect that the laser output can be easily increased in size by adding the laser amplifier.

Further, since the laser oscillator and the laser amplifier can be miniaturized, handling becomes easy, and the laser oscillator and the laser amplifier can be easily installed even in a narrow installation space. There is an effect that the maintenance is easy and the reliability of the device can be improved.

When a graded index optical fiber is used as the coupling optical fiber, the density of the laser light guided from the laser oscillator to the laser amplifier can be increased, so that high quality laser light can be obtained.

Further, since the laser light from the laser oscillator is introduced into the autocollimator of the laser amplifier, the beam diameter of the laser light incident on the solid rod of the laser amplifier is adjusted by adjusting the autocollimator. Therefore, there is an effect that the quality of the laser light amplified by the laser amplifier can be improved.

[Brief description of the drawings]

FIG. 1 is a schematic view showing an example of an embodiment of a solid-state laser generator according to the present invention.

FIG. 2 is a schematic diagram illustrating an example of an autocollimator.

FIG. 3 is a schematic view showing an example of a conventional solid-state laser generator.

FIG. 4 is a schematic diagram showing an example of a conventional solid-state laser generator configured to generate high-power laser light.

FIG. 5 is a schematic diagram showing an example of a conventional solid-state laser generator including a laser oscillator and a laser amplifier on one base plate.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Casing 2 Solid rod 3 Excitation lamp 4 Oscillator 6 and 7 Resonator mirror 9 Incident optical system 10 Output optical fiber 13 Oscillator 15 Incident optical system 21 Laser oscillator 22 Oscillator-side base 23 Laser amplifier 24 Amplifier-side base 25 Collimator 25A Autocollimator 26 Connecting optical fiber 26A Graded index optical fiber S Optical path

 ────────────────────────────────────────────────── ─── Continuing from the front page (72) Inventor Shigeki Iida 3-16-16 Toyosu, Koto-ku, Tokyo Ishikawajima Harima Heavy Industries, Ltd. Tokyo Engineering Center F-term (reference) 5F072 AB02 AK01 JJ01 JJ04 KK30 MM08 MM09 PP01 RR01 YY06

Claims (4)

[Claims] 1. A required number of oscillating parts provided in a casing of a solid rod of a laser medium and an excitation lamp corresponding to the solid rod on an oscillator side base on an optical path of the solid rod. A resonator mirror is arranged on the optical path of the rod so as to sandwich the oscillation part, and an incident optical system is arranged so as to approach the resonator mirror on the laser output side. The required number of oscillating units provided in the casing with the solid rod of the medium and the excitation lamp corresponding to the solid rod are arranged on the optical path of the solid rod,
And a laser amplifier having a collimator disposed on one side of the oscillating unit on the optical path of the solid rod and an incident optical system connected to an output optical fiber disposed on the other side of the oscillating unit. A solid-state laser generator, wherein an input optical system of an oscillator and a collimator of a laser amplifier are connected by a connection optical fiber. 2. The solid-state laser generator according to claim 1, wherein a plurality of laser amplifiers are provided, and the laser amplifiers are connected to each other by a connection optical fiber. 3. The solid-state laser generator according to claim 1, wherein a graded index optical fiber is used as the coupling optical fiber. 4. The solid-state laser generator according to claim 1, further comprising an autocollimator capable of adjusting a spot diameter of a beam incident on the solid rod, instead of the collimator.