JPH08213716A - Laser device - Google Patents

Abstract

PURPOSE: To effectively combine with one axis laser beams emitted from a plurality of laser units. CONSTITUTION: Respective laser beams 7 emitted from a plurality of laser units 1 (1a to 1n) are focused to one point of a combining optical element 6. The laser units 1 are pulse-driven with a driving power supply 2. The combining optical element 6 is rotated with a motor 4 in synchronization with the light emitting timing of the respective laser beams 7. Thereby, a highly repetitive pulse laser beam can be obtained by emitting a plurality of laser beams 7 with one axis.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a laser device constructed so that a plurality of laser beams of a low-repetitive-operation solid-state laser are uniaxially combined to supply a high-repetitive laser beam.

[0002]

2. Description of the Related Art Laser devices have been widely applied to fields such as laser processing, measurement, communication, and laser inertial fusion technology. An outline of a conventional laser device will be described with reference to FIG. FIG. 5 is an optical path diagram showing an outline of a beam combining mechanism in a solid-state laser device such as a YAG laser using a plurality of laser units.

In FIG. 5, reference numeral 1 is a laser unit, and a plurality of laser units 1a to 1n are arranged. A laser beam 7 emitted from these laser units 1 (1a to 1c ... 1n) is an axis adjusting mirror. The light is polarized by 5 and is incident on the half mirror 14, which is combined by the half mirror 14 and emitted as a combined laser beam 9. That is, the laser beams 7 emitted from the laser units 1 (1a to 1c ... 1n) are synthesized by using the same number of half mirrors 14 as the number of times of synthesis to obtain a synthesized laser beam 9 with an increased repetition frequency. .

[0004]

In a solid-state laser device such as a YAG laser, it is difficult to obtain a high oscillation repetition frequency by itself because the rod that serves as a laser medium has a poor cooling effect. Hz is the limit.

In the conventional laser device shown in FIG. 5, the number of laser beams obtained by increasing the repetition frequency is the same as the number of base laser beams, and it is not possible to extract a laser beam that is uniaxially synthesized.

Therefore, the peak power per obtained laser beam cannot be made equal to or higher than that of the base laser unit alone, and in order to avoid this, it is necessary to irradiate the combined beam collectively. Therefore, there is a problem that the usage conditions are extremely limited.

The present invention has been made to solve the above problems, and provides a laser device capable of efficiently synthesizing laser beams emitted from a plurality of laser units uniaxially to obtain a highly repetitive laser beam. To do.

[0008]

According to the present invention, a plurality of laser units, a driving power source connected to the laser unit, a timing adjusting unit connected to the driving power source, and a plurality of laser units are emitted. The axis adjusting mirror for adjusting the optical axis of each laser beam, the combining optical element for entering the laser beam emitted from the axis adjusting mirror, and the combining optical element are rotated to the timing adjusting unit. It is characterized by having a motor to be connected.

The present invention also includes a plurality of laser units, a driving power source connected to the laser units, and a timing adjusting unit connected to the driving power source,
An axis adjusting mirror that adjusts the optical axis of each laser beam emitted from the plurality of laser units, a Faraday rotator that receives the laser beam emitted from the axis adjusting mirror, and the Faraday rotator is rotated to perform the adjustment. And a Faraday rotator drive unit connected to the operating unit.

[0010]

According to the present invention, the emission axes of the laser beams emitted from the plurality of laser units are adjusted by the axis adjusting mirror and are accurately collected at one point in the combining optical element to be combined into one axis. The synthesizing optical element is rotated by a motor, and in synchronization with the rotation, the driving power source of each laser unit is operated and oscillated.

The accuracy of axis coincidence of the timing after laser beam synthesis is monitored by a monitor unit. By rotating the motor, a plurality of laser beams are emitted uniaxially to obtain a highly repetitive pulse laser beam.

Further, by using a Faraday rotator instead of a rotating mechanism by a motor, it is possible to eliminate the blurring of the beam axis due to mechanical vibration and to extract a laser beam with high repetition rate.

Further, the combined laser beam can be directly incident on a single optical fiber incidence optical system, transmitted by the optical fiber, and guided to the target.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A first embodiment of a laser device according to the present invention will be described with reference to FIGS. In FIG. 1, reference numeral 1 (1a ... 1n) denotes a laser unit for emitting a laser beam 7, and this laser unit 1 (1a ... 1n).
A drive power source 2 is connected to the. This drive power supply 2
Is connected to the timing adjusting unit 3, and the timing adjusting unit 3 is connected to the motor 4.

A combining optical element 6 composed of a mirror or a prism is connected to the motor 4. Each of the laser units 1 (1a ... 1n) is included in the synthesizing optical element 6.
The laser beam emitted from the laser beam and incident on the axis adjusting mirror 5 and refracted is combined at one point.

A sampling mirror 8 is provided on the optical path of the combined laser beam 9, and a sensor unit 10 for detecting the sampling beam sampled by the sampling mirror 8 is provided.
A monitor unit 11 for inputting the output signal of is arranged. The output signal of the monitor unit 11 is input to the motor 4.

In the first embodiment, however, the laser beams 7 emitted from the plurality of laser units 1 (1a ... 1n) are concentrated by the axis adjusting mirror 5 at one point on the surface of the synthesizing optical element 6. Is adjusted. The combining optical element 6 is rotated by the motor 4.

The driving power source 2 is driven for the laser unit 1 in which the rotation angle of the synthesizing optical element 6 is aligned with the direction of the emitted laser beam 7, and the oscillating laser beam 7 is directed to the emitting side of the synthetic laser beam 9. I will take it out.

At this time, the drive timing of the power source for driving the laser unit is adjusted by the timing adjusting unit 3 upon receiving a signal from the motor 4. In this way, the laser beams 7 emitted from the respective laser units 1 are sequentially combined with the rotation of the combining optical element 6 and taken out by the combining optical element 6.

Further, the synthetic laser beam 9 is formed by synthesizing the respective laser beams 7, and a part of the synthetic laser beam 9 is taken out by a sampling mirror in order to confirm that the beam axes thereof are completely coincident with each other. .

The emitted beam is detected by a sensor such as a CCD camera provided in the sensor unit section 10, and the monitor unit 11 confirms the matching accuracy of the beam axes. When a mismatch occurs, the laser unit from the corresponding laser unit The output beam axis is adjusted by the axis adjusting mirror 5 so that they coincide with each other with sufficient accuracy.

At the same time, the sensor unit 10 is provided with an optical pulse detector such as a photoelectric tube or a photo diode to monitor the rotation of the synthetic mirror and the oscillation timing of each laser unit, and the timing adjustment unit 3 drives each laser unit. Adjust the power timing. .

As a result of the above operation, as shown in FIG. 2, the oscillation pulse of each laser unit is uniaxially combined with the pulse oscillation laser beam from each laser unit 1a, 1b ... The laser beam increased by the number of laser units can be taken out.

Next, a second embodiment of the laser device according to the present invention will be described with reference to FIG. This second embodiment is the first
The part different from the example is that instead of the synthesizing optical element that is mechanically rotated in synchronization with the power source for driving the laser unit, the Faraday rotator that is electrically driven is used to synthesize the laser beam of each laser unit. To do. Note that FIG. 3 shows only the main part of the present embodiment, and the other parts are omitted because they are similar to FIG. Also, the first
The description of the same parts as those in the embodiment is omitted.

That is, in FIG. 3, the polarization of the laser beam 7 emitted from each laser unit 1 is aligned with the linearly polarized light, synchronized with the emission timing of each laser beam 7, and the polarization plane of the Faraday rotator 15 ( A similar uniaxial synthetic laser beam 9 can be obtained by electrically rotating the (direction) by the Faraday rotator drive unit 16. According to this embodiment, since there is no influence of vibration that is likely to occur in the rotating mechanism, the emission axis of the laser beam can be kept stable.

FIG. 4 shows a third embodiment of the present invention, in which an optical fiber incidence optical system for transmitting a combined laser beam 9 combined by the laser devices according to the first and second embodiments. 12 is provided, and an optical fiber 13 is provided in this optical system 12.
Is connected.

According to this embodiment, since the laser beams emitted by the laser devices according to the first and second embodiments are uniaxially combined, they are directly transmitted to the optical fiber 13 in addition to being transmitted in space. It can be incident and guided to the target.

[0028]

According to the present invention, when it is desired to obtain a pulsed laser beam having a repetition frequency higher than that which can be operated by a single laser unit, laser beams having an increased repetition frequency can be combined and emitted uniaxially.

Thus, the problem of the beam loss component in the conventional half mirror has been solved, the synthesis efficiency is improved, and the laser beam can be extracted as a uniaxially synthesized laser beam which cannot be obtained in the conventional example.

[Brief description of drawings]

FIG. 1 is an optical path system diagram showing a partial block of a first embodiment of a laser device according to the present invention.

FIG. 2 is a waveform diagram showing an oscillation pulse of each laser unit of the laser device in FIG. 1 and a pulse after combination.

FIG. 3 is an optical path system diagram conceptually showing a main part of a second embodiment of a laser apparatus according to the present invention.

FIG. 4 is a system diagram showing a main part of a third embodiment of a laser device according to the present invention.

FIG. 5 is an optical path system diagram showing a conventional laser device.

[Explanation of symbols]

1 ... Laser unit, 2 ... Laser driving power source, 3 ...
Timing adjusting unit, 4 ... Combining optical element rotating motor, 5 ... Shaft adjusting mirror, 6 ... Combining optical element, 7 ...
Laser beam, 8 ... Sampling mirror, 9 ... Synthetic laser beam, 10 ... Sensor unit, 11 ... Monitor unit, 12 ... Optical fiber incident optical system, 13 ... Optical fiber, 14 ...
Half mirror, 15… Faraday rotator, 16… Faraday rotator drive unit.

Continuation of the front page (72) Inoue Motohisa Abe 1-1-1, Shibaura, Minato-ku, Tokyo Inside Toshiba Head Office

Claims (6)

[Claims] 1. A plurality of laser units, a driving power supply connected to the laser units, a timing adjustment unit connected to the driving power supply, and light of each laser beam emitted from the plurality of laser units. It is equipped with an axis adjusting mirror for adjusting the axis, a combining optical element for entering a laser beam emitted from the axis adjusting mirror, and a motor for rotating the combining optical element and connecting it to the timing adjusting unit. Laser equipment characterized by. 2. The laser device according to claim 1, wherein the combining optical element comprises a mirror or a prism. 3. The timing adjusting unit operates the driving power source in synchronization with the rotation frequency of a motor for rotating the synthesizing optical element to oscillate each of the laser units and adjusts the timing of the driving power source. The laser device according to claim 1, further comprising an adjusting mechanism. 4. A sampling mirror for sampling a part of a laser beam emitted from the combining optical element, a sensor unit for detecting the laser beam from the sampling mirror, and a combined laser beam from the sensor unit. The laser device according to claim 1, further comprising a monitor unit that monitors the accuracy of axis matching and the state of synchronization with the drive power source and the motor. 5. A plurality of laser units, a driving power source connected to the laser units, a timing adjusting unit connected to the driving power source, and light of each laser beam emitted from the plurality of laser units. An axis adjusting mirror for adjusting the axis; a Faraday rotator for injecting a laser beam emitted from the axis adjusting mirror; and a Faraday rotator drive unit for rotating the Faraday rotator and connecting the Faraday rotator to the adjusting unit. Characteristic laser device. 6. The laser device according to claim 1, further comprising an optical fiber incidence optics and an optical fiber for injecting a synthetic laser beam synthesized at one point by the synthesizing optical element or the Faraday rotator. .