JPH0856036A - Laser amplifier equipment - Google Patents

Abstract

PURPOSE:To improve amplification efficiency, reduce manhours for maintenance and adjustment, and supply a stable laser beam to an amplifier. CONSTITUTION:This laser amplifier equipment is provided with the following a master oscillation equipment 18 of a laser oscillation source, an injection lock oscillation equipment 19 which performs slant axis resonance, an aperture 14 for cutting out uniform intensity distribution of an output laser beam of the injection lock oscillation equipment 19, a laser amplifier 17, a sampling mirror 12 which samples a laser beam which has passed the aperture 14, a beam monitor equipment 13 which monitors the intensity distribution of a sampling beam, and a magnification optical system 15 which adjusts the beam size in the manner in which the laser beam cut by the aperture 14 can be made to enter an amplifier 17.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a laser amplifying device for obtaining a high-power laser used for laser processing, for example.

[0002]

2. Description of the Related Art As shown in FIG. 6, a conventional laser amplification apparatus combines a master oscillation device 18 which is a laser oscillation source and an injection lock oscillation device 19 to generate a laser beam emitted from the injection lock oscillation device 19. It is composed of a magnifying optical system 15 that magnifies to a laser diameter required to amplify the diameter, and an amplifier 17 that amplifies a high-quality laser beam emitted from the magnifying optical system 15 to generate a high-power laser beam.

The master oscillator 18 is a laser oscillator 2
And a concave mirror 1 disposed on both sides of the laser oscillator 2 and an emission optical system 3 for taking out a laser beam incorporating the convex mirror.

Further, the injection lock oscillator 19
Is a concave mirror 7 having a laser light incident part in the center for passing the laser beam emitted from the master oscillator 2, an injection lock oscillator 8, and a confocal point with the concave mirror 7 on the laser emission side of the injection lock oscillator 8. Thus, the convex mirror 10 is arranged so as to face each other, and the exit mirror 9 for passing the laser beam is provided in the central portion of the convex mirror 10 that is arranged so as to be inclined with respect to the optical axis of the laser beam.

The laser beam emitted from the injection lock oscillator 8 is expanded by the expansion optical system 15 and then incident on the amplifier 17 for amplification.

Between the master oscillator 18 and the injection lock oscillator 19, there is provided a first adjusting reflecting mirror 4 for accurately guiding the laser beam emitted from the master oscillator 18 to the reduction optical system 6. (4a and 4b),
The reduction optical system 6 installed in the injection lock oscillator 19 for reducing the laser beam, and a second for accurately guiding the laser beam reduced by the reduction optical system 6 to the injection lock oscillator 19. And the adjusting reflection mirror 5 (5a and 5b).

The master beam emitted from the master oscillating device 18 is incident on the concentric axis from a light entrance portion provided in the center of the concave mirror 7 in the injection lock oscillating device 19 and is output as a high quality laser beam. It has become.

Between the injection lock oscillator 19 and the amplifier 17, an adjusting reflecting mirror 20 for accurately entering the emitted laser beam into the magnifying optical system 15 is provided.
(20a, 20b), a magnifying optical system 15 having a laser aperture required for the amplifier 17, and an adjusting reflecting mirror 16 (16a) for accurately guiding the laser beam after passing through the magnifying optical system 15 to the amplifier 17. , 16b) are provided.

The laser beam profile before entering the magnifying optical system 15 has a hole necessary for resonance at the center of the beam at the position a in FIG. 6 (a) as shown in FIG. 6 (b). Since there is the shadow of the opened exit mirror 9 and the shadow of the metal (vapor source) inside the injection lock oscillator 8 (not shown) at the lower end, it has a non-uniform spatial intensity distribution.
The beam profile at f in the drawing after passing through the expansion optical system 15 is also a similar beam profile as shown in FIG. 6B.

Next, an example of the planar arrangement of the conventional laser amplifying device shown in FIG. 6A will be described with reference to FIG. 7 which is a plan view. Flat platens are provided on both sides of the master oscillator tube 27. A resonator including an emitting mirror 3 for emitting a laser beam, in which a concave mirror 1 and a convex mirror are arranged to face each other, is arranged on these flat surface plates.

A total reflection concave mirror 21 having a laser incident part at the center for passing the laser beam emitted from the master oscillation tube 27 and a laser beam light facing the concave mirror 21 on the laser emission side of an injection lock oscillation tube 28. An emission mirror 9 having a laser beam passage hole provided in the center of a convex mirror 10 arranged to be inclined with respect to an axis is arranged on a flat surface plate.

A magnifying optical system 15 for magnifying the injection lock beam emitted from the injection lock oscillator 28 is arranged on a flat surface plate. The magnifying optical system
An amplifier 17 (17
a, 17b), the amplifier oscillator 29 (29a, 29b) and the amplifier controller 25 (25a, 25b) are horizontally arranged.

Each of the oscillation tubes 27 and 28 needs to be replenished with a metal vapor source on a regular basis and needs to be removed for maintenance, so that the controllers 24a and 24b of the oscillation tubes 27 and 28 are oscillated inside. The pipes 27 and 28 are arranged outside.

When taking out and maintaining these oscillating tubes 27, 28, only the oscillating tubes 27, 28 are removed from the support plate fixed to the apparatus, or the entire laser apparatus including the controllers 24, 25 is moved.

[0015]

In the conventional laser amplifying apparatus, the laser beam emitted from the injection lock oscillator 19 has a shadow of the convex mirror 10 generated in the central portion of the emitting mirror 9 necessary for resonance and an injection at the lower end. There is a shadow of the metal (vapor source) inside the lock oscillator 8.

Therefore, the beam shape is as shown in FIG. 6 (b). This beam is expanded as it is by the expansion optical system 15 and is incident on the amplifier 17 to be amplified. The amplified laser beam also has similar laser intensity. The intensity distribution of the laser beam is as shown by the curve e in FIG.

As described above, in the conventional laser amplifying apparatus, the maximum performance of the amplifier 17 is not fully utilized, so that the loss of the laser intensity and the deterioration of the laser beam quality are observed. Further, when a plurality of amplifiers 17 are arranged in series, the entire system is adversely affected and a problem arises in using the obtained laser beam.

Further, since all the parts of the laser device are arranged horizontally, if the access area for maintenance of the laser device, adjustment of the optical system, etc. is included, installation of a large laser amplification device requires a large amount of cost. is there.

Further, the oscillation tube is a glass of an electrically insulating material,
Since it is divided in the longitudinal direction with ceramics or the like, the glass or the like may be damaged during maintenance of the oscillation tube, and there is a problem in that the entire laser device must be moved to the maintenance location.

The present invention has been made to solve the above problems, and provides a laser amplifying device capable of preventing loss of a laser beam and deterioration of the quality of the laser beam, improving efficiency, and obtaining a high-quality laser beam. To provide.

[0021]

The present invention has a master oscillator having a master oscillator which is a laser oscillator, and an injection-locked oscillator tube for entering a laser beam emitted from the master oscillator to cause oblique axis resonance. An injection lock oscillator, an aperture for cutting out a uniform intensity distribution component of an output laser beam of the injection lock oscillator, and a laser amplifier for injecting the laser beam cut out from the aperture are provided.

Further, the present invention is a master oscillation device having a master oscillator which is a laser oscillation source, and an injection lock oscillation device having an injection lock oscillation tube for injecting a laser beam emitted from the master oscillation device to cause oblique axis resonance. A reduction optical system for injecting the laser beam emitted from the master oscillator into the injection lock oscillator, and an aperture for cutting out a uniform intensity distribution component of the laser beam emitted from the injection lock oscillator, It is characterized by comprising an expanding optical system for adjusting the beam size of the laser beam cut out by the aperture, and an amplifier for injecting the laser beam emitted from this expanding optical system.

[0023]

[Function] Since only the component of the spatial intensity distribution of the laser beam emitted from the injection lock oscillator is incident on the amplifier, the non-uniformity of the laser beam intensity distribution after amplification is eliminated and the amplification capability of the amplifier is maximized. You can make use of it.

Since the concave-convex surface mirror of the injection lock oscillator and the exit mirror are arranged in oblique axis resonance so that the shadow of the exit mirror is located at the end of the emitted laser beam,
The injection lock beam can be effectively taken out by the aperture.

By providing the beam monitor after passing through the aperture, the aperture installation position can be optimized and a stable beam can be always supplied to the amplifier.

That is, the shadow of the laser emitting mirror is moved to the end of the laser beam. A circular high-quality laser beam can be obtained by an aperture arranged so that a uniform intensity distribution component of the laser beam emitted from the emitting mirror can be taken out.

A few percent of the laser beam that has passed through this aperture is sampled by a sampling mirror, and the sampled beam is monitored by a beam monitor.
A beam shape at the time of adjusting the oblique axis resonance and adjusting the aperture is measured.

A high-efficiency and high-quality laser beam can be obtained by the expanding optical system for expanding the high-quality laser beam reflected by the sampling mirror and the amplifier for amplifying the laser beam passing through this expanding optical system.

Further, the master oscillator and the injection lock oscillator are installed on the upper and lower sides, the optical system is installed on the standing platen, and the laser beam is arranged on the upper and lower sides, so that the installation area is reduced to about 1/2, and maintenance and adjustment are performed. Since access can be made from one side, the access area can be reduced to about 1/2. Labor-saving in maintenance of the laser oscillator tube, easy adjustment of the optical system, and cost reduction due to the reduction of installation are obtained.

The laser oscillation tube is supported on a metal support by an insulating support, and the maintenance of the laser oscillation tube is taken out together with the metal support so that the laser oscillation tube is made of an insulating material such as glass or ceramics. Can prevent damage accidents.

Since maintenance can be performed by moving only the laser oscillation tube and its support structure, it is possible to save labor time, reduce maintenance space, and simplify maintenance work.

[0032]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A first embodiment of a laser amplifying device according to the present invention will be described with reference to FIGS. FIG. 1 is a device layout view of a laser amplification device in the first embodiment, and FIG. 2 is a schematic side view of FIG.

In FIG. 1, reference numeral 18 denotes a master oscillator, 19
Is an injection lock oscillator. The master oscillator 18 has a built-in master oscillator 2, and the master oscillator 2
The concave reflecting mirror 1 and the emission optical system 3 are arranged so as to face each other. The exit optical system 3 is composed of a convex mirror and an exit mirror (not shown).

The injection lock oscillator 19 has a built-in injection lock oscillator 8, a concave mirror 7 having an incident part for transmitting the laser beam emitted from the master oscillator 18 to the oblique axis, and a laser on the emission side of the injection lock oscillator 8. The concave mirror 7 with the beam tilted
It is composed of an emitting mirror 9 having a laser beam passage hole which is arranged so as to oppose to, and a convex mirror 10 which is arranged in the laser beam passage hole of the emitting mirror 9 so as to have an oblique axis resonance with the concave mirror 7.

The first adjusting reflector 4 (4a, 4a, 4a, 4b) is provided between the master oscillator 18 and the injection lock oscillator 19.
4b), the reduction optical system 6 and the second adjusting reflecting mirror 5 (5
a, 5b) are arranged.

On the optical path of the convex mirror 10, a reflecting mirror 11, an aperture 14, a sampling mirror 12 and a beam monitor device 13 are provided.
The magnifying optical system 15, the third adjusting reflecting mirror 16 and the amplifier 17 are arranged on the reflection optical path from the sampling mirror 12.

Here, the master oscillator 2 is a laser beam oscillation light source, and the first adjusting reflecting mirrors 4a and 4b adjust the optical axis of the laser beam emitted from the master oscillator 2. The reduction optical system 6 reduces the optical diameter of the laser beam required for the injection lock oscillator 8, and
The adjusting reflecting mirror 5 (5a, 5b) adjusts the reduced laser beam to the optical axis of the injection lock oscillator 8.

The concave mirror 7 is a light entering portion for transmitting the laser beam emitted from the master oscillator 2, and the emitting mirror 9 is the light emitted from the injection lock oscillator 8 and is arranged so as to be inclined to the optical axis and to face the concave mirror 7. It has a laser beam transmission hole.

The injection lock oscillator 19 is a laser output section, and the aperture 14 is arranged so as to extract a uniform intensity distribution component of the laser beam emitted from the emitting mirror 9. The sampling mirror 12 is for obtaining a sampling beam c of several% from the laser beam that has passed through the aperture 14.

The beam monitor device 13 monitors the sampling beam c. The magnifying optical system 15 magnifies the laser beam d reflected from the sampling mirror 12,
The amplifier 17 amplifies the laser beam e that has passed through the magnifying optical system 15.

Next, the three-dimensional structure of the laser amplifying apparatus according to this embodiment will be described with reference to FIG. In FIG. 2, reference numeral 26 (26a, 26b) is a stand surface plate on which an optical element can be installed on a surface perpendicular to the horizontal plane. The left side surface plate 26a has an emission optical system 3, a reduction optical system 6 and a second reflecting mirror 5a. , 5b are installed. A master oscillator tube 27 (corresponding to 2 in FIG. 1) is provided on the upper right side of the stand plate 26a on the left side, and an injection lock oscillator tube 28 (corresponding to 8 in FIG. 1) is provided below the master oscillator tube 27.
Are fixed by a metal support base 30 via an insulating support 31.

A concave reflecting mirror 1, an emitting mirror 9, a convex mirror 10, adjusting reflecting mirrors 20b and 20c, and a magnifying optical system 15 are installed on the stand plate 26b on the right side of the master oscillating tube 27 and the injection lock oscillating tube 28. Has been done. The laser beam emitted from the magnifying optical system 15 enters the amplifier.

The laser oscillating tubes supported by the electrically insulating support 31 fixed to the metal supporting base 30 as described above are installed vertically, one is the master oscillating tube 27 and the other is the injection lock oscillating tube 28. And These oscillator tubes 27,
The stand surface plates 26a and 26b are provided on both sides of 28,
The optical system is installed on 26a and 26b as described above.

Therefore, according to the first embodiment, the concave mirror 7 and the convex mirror 10 are provided in the injection lock oscillator 19.
And the output mirror 9 are arranged so that the oblique axis resonance can be performed.

As a result, the beam profile at the position a in FIG. 1 makes it possible for the shadow of the exit mirror 9 to move to the beam end as shown in FIG. 3, and as shown in FIG. In addition, it is possible to maximize the use of the component having a uniform beam space intensity distribution as the component to be cut out.

Therefore, by providing the beam monitor device 13 capable of measuring the beam spatial intensity distribution after passing through the aperture 14, it is possible to optimize the installation position of the aperture 14 and monitor the beam quality.

Further, according to the three-dimensional arrangement example shown in FIG. 2, the master oscillation tube 27 and the injection lock oscillation tube 28 are
Are arranged above and below, and the installation area is halved, and since the optical system is installed on the stand surface plate 26, its adjustment becomes easy. Further, each of the oscillation tubes 27 and 28 is a metal support base.
Since it is supported by 30, the oscillator tubes 27 and 28 are
Only can be easily moved and maintained.

With the above operation, the intensity distribution of the laser beam emitted from the injection lock oscillator 19 can always stably enter only the uniform component as shown by the curve f in FIG. Therefore this amplifier
The amplification capacity of 17 can be used to the maximum, a stable amplified beam can be obtained at all times, and the installation area is reduced to about 1/2, and maintenance and adjustment are easy.

Next, a second embodiment of the laser amplifying device according to the present invention will be described with reference to FIG. The laser amplification device according to the second embodiment includes a master oscillation device 18 as a laser oscillation light source and an injection lock oscillation device 19 as a laser output section.
Has a light emitting optical system 3 and a concave reflecting mirror 1 which are arranged on opposite sides of the laser oscillator 2.

The injection lock oscillator 19 is capable of semi-transmission of the total reflection concave mirror 21 and the master oscillation beam, which are arranged to face each other on both sides of the injection lock oscillator 8 so as to resonate obliquely, and the transmission surface is concave and the reflection surface is convex. The meniscus mirror 22 is provided, and the partially transmissive emission optical system 20 is provided so as to be inclined to the optical axis on the light output side of the injection lock oscillator 8 so as to face the total reflection concave mirror 21.

A coating for semi-transmitting the master beam, for example, is applied to the outer surface of the output optical system 20, and a semi-reflective coating is applied to the inner surface as a passage required for oblique axis resonance.
It has a coating that totally reflects the others.

Further, the adjusting reflection mirror 4 (4a, 4b) for making the laser beam emitted from the master oscillator 18 enter the incident optical system 23, and the master beam optimally enter the injection lock oscillator 19. An incident optical system 23 for arranging is arranged. An aperture 14 is installed after the reflecting mirror 11 so that a uniform intensity distribution component of the laser beam can be taken out.

A sampling mirror 12 for extracting a sampling beam of several% from the laser beam b which has passed through the aperture 14 is arranged, and a beam monitor device 13 for monitoring the sampling beam c and the sampling mirror 12 are reflected. A magnifying optical system 15 for magnifying the laser beam d and an amplifying device 17 for amplifying the laser beam passing through the magnifying optical system are arranged. Since the other parts are the same as those in the first embodiment, the description thereof will be omitted.

According to the second embodiment, by arranging the partial transmission type output mirror 20 in a position where the partial transmission type output mirror 20 and the meniscus mirror 22 in the injection lock oscillator 19 can perform oblique axis resonance, The beam profile at the position a in 5 is as shown in FIG. 3, and the beam component of, for example, the semi-reflective coated portion of the light passage opening of the partially transmissive emission mirror 20 is similar to the shadow of the emission mirror hole. It is possible to move to the beam end.

Also, if only a uniform component of the beam space intensity distribution is extracted by the aperture 14, the beam profile at the position of b can maximize the use of the laser beam as shown in FIG.

Further, by providing the beam monitor device 13 capable of measuring, for example, the beam space intensity distribution after passing through the aperture, it becomes possible to optimize the installation position of the aperture 14 and monitor the beam quality. The intensity distribution of the beam obtained in the second embodiment is flat as shown by the curve f in FIG.

In the second embodiment, as in the first embodiment, only the uniform component of the laser beam emitted from the injection lock oscillator 19 can always be stably input to the amplifier 17. The amplification ability can be maximized and a stable amplified beam can be obtained at all times.

[0058]

According to the present invention, a uniform spatial intensity distribution component is effectively taken out by the aperture as an oblique-axis resonance of an injection lock beam, and the beam is constantly monitored by a beam monitor so that only a uniform component is obtained. It becomes possible to always stably enter the amplifier.

Therefore, the amplification capability of the amplifier can be utilized stably and to the maximum, and the installation area can be reduced to reduce the cost and save labor for maintenance and adjustment.

[Brief description of drawings]

FIG. 1 is a configuration diagram showing a first embodiment of a laser amplifying device according to the present invention.

FIG. 2 is a schematic side view of FIG.

FIG. 3 is a beam profile diagram at point a in FIG.

FIG. 4 is a beam profile diagram at point b in FIG.

FIG. 5 is a configuration diagram showing a second embodiment of the laser amplifying device according to the present invention.

6A is a configuration diagram showing a conventional laser amplification device, and FIG. 6B is a beam profile diagram at point a in FIG. 6A.

FIG. 7 is a plan view showing the development of FIG.

FIG. 8 is a curve diagram showing a comparison of beam intensity distributions obtained by the example of the present invention and the conventional example.

[Explanation of reference numerals] 1 ... concave reflecting mirror, 2 ... master oscillator, 3 ... exit optical system,
4 ... 1st adjustment reflecting mirror, 5 ... 2nd adjustment reflecting mirror, 6
... reduction optical system, 7 ... concave mirror, 8 ... injection lock oscillator, 9 ... exit mirror, 10 ... convex mirror, 11 ... reflecting mirror, 12 ...
Sampling mirror, 13 ... Beam monitor, 14 ... Aperture, 15 ... Enlarging optical system, 16 ... Reflector for third adjustment, 17 ... Amplifier, 18 ... Master oscillator, 19 ... Injection lock oscillator, 20 ... For adjustment Reflective mirror, 21 ... Reflective concave mirror, 22
… Meniscus mirror, 23… Incident optical system, 24… Oscillator controller, 25… Amplifier controller, 26… Stand plate, 27… Master oscillator tube, 28… Injection lock oscillator tube, 29… Amplifier oscillator, 30 … Supporting table, 31… Supporting device.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Ryoichi Otani Ryoichi Otani No. 8 Shinsugita-cho, Isogo-ku, Yokohama-shi, Kanagawa Stock company, Toshiba Yokohama Works (72) Inventor Tokuyasu Kobayashi No. 8 Shinsugita-cho, Isogo-ku, Yokohama-shi, Kanagawa Company Toshiba Yokohama Office (72) Inventor Abe Motohisa 1-1-1, Shibaura, Minato-ku, Tokyo Inside Toshiba Head Office Co., Ltd. (72) Inventor Keiichi Hirota 2-24 Harumicho, Fuchu-shi, Tokyo East Shiba FA System Engineering Co., Ltd.

Claims (6)

[Claims] 1. A master oscillator having a master oscillator which is a laser oscillation source, an injection lock oscillator having an injection lock oscillator for injecting a laser beam emitted from the master oscillator to cause oblique axis resonance, and A laser amplification device comprising an aperture for cutting out a uniform intensity distribution component of an output laser beam of an injection lock oscillator and a laser amplifier for injecting the laser beam cut out from this aperture. 2. A master oscillating device having a master oscillator which is a laser oscillating source, an injection lock oscillating device having an injection lock oscillating tube for obliquely resonating upon incidence of a laser beam emitted from the master oscillating device, and A reduction optical system for injecting the laser beam emitted from the master oscillator into the injection-lock oscillator, an aperture for cutting out a uniform intensity distribution component of the laser beam emitted from the injection-lock oscillator, and this aperture. A laser amplification device comprising: a magnifying optical system that adjusts the beam size of the generated laser beam; and an amplifier that inputs the laser beam emitted from the magnifying optical system. 3. A sampling mirror for sampling a laser beam that has passed through the aperture, and a beam monitor device for monitoring the intensity distribution of the sampling beam from the sampling mirror. The laser amplification device according to claim 2. 4. The laser amplifying device according to claim 1, wherein the master oscillator and the injection lock oscillator are vertically arranged. 5. The master oscillator and the injection lock oscillator are configured as one unit, and accessory devices such as a controller for each oscillator are installed on the side opposite to the side where the two upper and lower laser oscillation tubes are arranged. Claim 1 characterized by
The laser amplification device according to claim 2. 6. The master oscillator, the injection lock oscillator, and the laser oscillator tube of the amplifier are supported by a supporter electrically insulated from a metal support base. The laser amplification device described.