JPH06224499A - Laser oscillator - Google Patents

Abstract

PURPOSE:To improve a light convergence efficiency, an oscillation efficiency, to facilitate cooling of a rod and to reduce in size of an entire apparatus by providing a reflector body having a reflecting surface on an inner surface, and a reflector chamber to be externally engaged with the body in a liquidtight state in a lamp casing. CONSTITUTION:A lamp casing 12 integrally provides a reflector body 12A and a reflector chamber 12B, and arranges a stepped sealing hole 12a of a wall of the chamber 12B and a sealing member 18. A sealing groove 17 and the member 18 are arranged on a connecting part of the chamber 12B to a rod casing 11. The chamber 12B covers the outside of the body 12A, and its terminal board 12b also covers an end of the body 12A. Thus, assembling of the casing, the rod and an exciting lamp is facilitated.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a laser oscillating device, and more particularly to shortening the distance between a laser light generating rod and an excitation lamp, as well as between rods and rods.
The present invention relates to a technique for improving oscillation efficiency by shortening the distance between resonance mirrors.

[0002]

2. Description of the Related Art In a rod-type solid-state laser such as Nd / YAG, a plurality of laser light generating rods (hereinafter, The rods (abbreviated as rods) are arranged in a cascade on the same optical axis.

Further, as shown in FIG. 7, an appropriate number of excitation lamps 2 such as arc lamps for generating excitation light are arranged on the side of the rod (laser light generating rod) 1, and the excitation lamp 2 is provided. A reflector cylinder 3 for reflecting the excitation light and irradiating the rod 1 in a concentrated manner is arranged around the. Then, excitation light is applied to each of the plurality of rods 1 to bring the rods into an excited state, and the laser light is caused to reciprocate between the rear mirror and the output mirror that face each other at the above-described separated positions, thereby making a laser oscillation state. . In FIG. 7, reference numeral 4 is a rod holder, 5 is an electrode, and 6 is a lamp holder.

On the other hand, in the laser oscillator, since the rod 1 is heated by the excitation energy and the outside is cooled by water or the like, the rod 1 is heated on the basis of the occurrence of temperature distribution or the change of the refractive index due to the internal stress. A phenomenon called a thermal lens effect that causes the optical property of a convex lens is likely to occur. Therefore, the parallel state between the path of the laser light between the rods 1 and the optical axis is broken, and the volume that contributes to oscillation inside the rod 1, that is, the laser volume, tends to decrease, and the oscillation efficiency tends to decrease. Become.

Conventionally, in order to prevent the deterioration of the oscillation efficiency, both ends of the rod 1 have a curvature in consideration of the thermal lens effect, for example, in the case of the rod 1 having a length of 152 mm and a diameter of about 8 mm. A concave surface is preliminarily processed so that the radius becomes -2 m to -1 m to improve the oscillation efficiency.

[0006]

However, in the conventional laser oscillating device shown in FIG. 7, the temperature of the rod 1 does not rise to the temperature at which the thermal lens effect occurs at the initial stage of startup, The concave lens effect on the end face of the rod 1 functions, the generated laser light is likely to be dispersed to the outside, and a large excitation energy is required until the oscillation state is reached, so that the threshold value becomes high and the startability is impaired. Become. In order to improve the startability and improve the above-mentioned oscillation efficiency, it is effective to make the rod-rod distance as small as possible when the rods are arranged in series. It is necessary to reduce the length of the rod holder 4 and the lamp holder 6 that are present.
Of these, the rod holder 4 may be shortened, but it is technically difficult to shorten the lamp holder 6 due to the length of the electrode 5. Further, in order to keep the rod 1 at a low temperature, it is desirable to cool the rod 1 by flowing cooling water around the rod 1 or the like. There remains a problem that it is necessary to supply the cooling water while suppressing the protrusion amount of the holder 4.

The present invention has been made in view of these circumstances, and it is possible to improve the light collection efficiency, the oscillation efficiency, the rod cooling easily, and the miniaturization of the entire apparatus. The purpose is to do.

[0008]

[Means for Solving the Problems] Various means for solving these problems are proposed. A laser oscillation device according to claim 1, wherein a laser beam generating rod, and an excitation lamp disposed laterally of the laser beam generating rod for irradiating excitation light,
A laser oscillating device having a casing for accommodating a laser light generating rod and an excitation lamp and having a reflection surface formed on the inner surface thereof, the casing enclosing the laser light generating rod, and a side of the rod casing. A lamp body casing that surrounds the excitation lamp and a fastener that integrates the rod portion casing and the lamp portion casing, and the lamp portion casing includes a reflector main body having a reflective surface on the inner surface thereof, and a liquid in the reflector main body. A structure including a reflector chamber that is externally fitted in a dense state is adopted. The laser oscillation device according to claim 2 has a configuration in which the reflection surface is formed on the inner wall of the cavity having a cross section in which two ellipses are overlapped in the major axis direction.
It is arranged to be added to the oscillator of claim 1. According to a third aspect of the laser oscillation device, a configuration in which a lamp holder surrounding an electrode of an excitation lamp is arranged in a protruding state at an end of a lamp portion casing is added to the oscillation device of the first or second aspect. ing. The laser oscillator according to claim 4 has a configuration in which a recessed portion in a state close to the laser light generating rod is arranged on the outer side of the rod casing, and the oscillator according to claim 1, 2 or 3. It is added to. The laser oscillation device according to claim 5, wherein a rod end plate is attached in a liquid-tight state to an end portion of the rod portion casing, and cooling water is supplied to the rod end plate for supplying cooling water around the laser light generating rod. The structure in which the path is formed is added to the oscillating device according to claim 1, claim 2, claim 3, or claim 4. The laser oscillator according to claim 6 has a configuration in which the cooling water supply passage is arranged along a direction inclined with respect to the facing direction of the laser light generating rod and the excitation lamp. I am trying to add it.

[0009]

The laser oscillator according to the first aspect is assembled by fastening the rod casing and the lamp casing with fasteners. At this time, if the reflector main body and the reflector chamber are fitted and integrated with each other, a liquid-tight state is formed between the rod portion casing and
The entire casing is hermetically sealed. In the laser oscillator according to the second aspect, in addition to the operation according to the first aspect, the laser light generating rod and the excitation lamp are exposed, disassembled, and assembled by disassembling and assembling the rod casing and the lamp casing. . By making the cross-sectional shape of the cavity an ellipse, the irradiation property of the excitation light to the laser light generation rod is improved. In the laser oscillator according to the third aspect, in addition to the operation according to the first or second aspect, the lamp holder is detachable from the rod casing together with the excitation lamp and the lamp casing. In the laser oscillator according to claim 4, in addition to the operation according to claim 1, claim 2 or claim 3,
By positioning the lamp holder of the excitation lamp adjacent to the recess of the casing in the cascade arrangement, the rod-rod distance is reduced. In the laser oscillation device according to the fifth aspect, in addition to the action according to the first, second, third or fourth aspect, the cooling water is sent around the laser light generating rod from the cooling water supply passage. , The rod is cooled. In the laser oscillator according to the sixth aspect, in addition to the operation according to the fifth aspect, the cooling water supply passage is located between the lamp holders during the cascade arrangement, and mutual interference is avoided.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the laser oscillator according to the present invention will be described below with reference to FIGS. In each figure, reference numeral 10 is a casing, 11 is a rod portion casing, 12 is a lamp portion casing, 12A is a reflector body, 12B is a reflector chamber, 13 is a fastening portion, 14 is a cavity, 15 is a rod end plate, 16 is cooling water. A supply passage, 17 is a seal groove, and 18 is a seal member.

The casing 10 is made of a metal material such as stainless steel or a ceramic material, and has a structure in which a rod portion casing 11, a lamp portion casing 12 and a rod end plate 15 are combined and integrated by a fastening portion 13. It Inside the casing 10, a reflecting surface having the function of the reflecting cylinder of the example in FIG. 7 is provided by applying gold coating or the like on the inner surface to increase the reflectance of light rays, or by attaching a thin plate having a high reflectance integrally. Three
Are integrally formed.

As shown in FIG. 1, the rod portion casing 11 encloses both sides of the rod 1 with a cavity portion 14 therebetween, and a semicircular recess 19 is formed on the outer portion thereof. 12 (Reflector body 12
A step portion 11a for inserting the reflector main body 12A is formed at a joint portion with A), and as shown in FIG. 1, a screw hole for the fastening portion 13 and the pin hole 11b communicating with the recess portion 19 is formed on the outer wall. The hole 11c is opened.

As shown in FIGS. 1 and 2, the lamp portion casing 12 is formed by integrating a reflector body 12A and a reflector chamber 12B, and a positioning pin 20 and a fastening portion 13 are arranged between them. Then, the stepped seal hole 12a and the seal member 18 are arranged in the wall portion of the reflector chamber 12B through which the fastening portion 13 penetrates. Then, in the reflector chamber 12B, a seal groove 17 and a seal member 18 are arranged at the joint portion with the rod casing 11 as shown in FIGS. 2 and 3.
Further, the reflector chamber 12B covers the outside of the reflector body 12A as shown in FIG.
The end plate portion 12b also covers the end portion of the reflector body 12A as shown in FIG. 2, and the end plate portion 12b has a lamp insertion hole 12c for projecting the end portion of the excitation lamp 2.
And the lamp holder 6 is attached.

As shown in FIGS. 1 and 2, the cavity 14 is a hollow portion for laser oscillation surrounded by a rod casing 11 and a pair of reflector bodies 12A, and its cross section has two cross sections. The shape of the ellipse is set so as to partially overlap in the major axis direction, the rod 1 and the excitation lamp 2 are arranged in the vicinity of the focal point of the ellipse, and the above-mentioned reflection surface 3 is formed on the inner wall surface.

The rod end plate 15 is shown in FIG.
As shown in FIGS. 4 and 5, as a whole, it has a plate shape or a block shape having a thickness larger than that of the end plate portion 12b of the lamp casing 12, and is separated from the joint portion with the end plate portion 12b and is connected to the rod 1. A cooling water supply passage 16 is formed in a direction inclined by, for example, 45 degrees with respect to the direction opposite to the excitation lamp 2, a holder insertion hole 15a is opened in the central portion, and a rod holder 4 having a shortened length is inserted. Seal member 1
8 is liquid-tight and the holder insertion hole 15
As shown in FIG. 4, recesses 19 are arranged on both sides of a. In FIG. 2, reference numeral 4a is a connection flow path for supplying cooling water, which is arranged in a plurality of divided states in the circumferential direction, for example.

As shown in FIGS. 1, 2 and 3, the seal groove 17 is formed on the joint surface of the reflector chamber 12B. In the example of FIG.
1, the seal member 18 is in contact with the reflector body 12A and the reflector chamber 12B, so that the mutual sealability is ensured.

When assembling the laser oscillator,
As shown in FIG. 6, the directions of the casings 10 are shifted by 90 degrees, the lamp holders 6 projecting in the longitudinal direction from the casings 10 of the same type are arranged in the recesses 19 of one casing 10, and the adjacent rod holders 4 are arranged. When they are brought close to each other, the rods 1 are in a cascade arrangement on the same optical axis.

With such a structure, adjacent portions of the lamp holder 6 do not interfere with each other in the longitudinal direction, so that the dimension of the shortened rod holder 4 corresponds to that of the rod 1.
It is directly linked to the reduction of the interval.

On the other hand, in the case where the rods 1 and the like are arranged in a cascade arrangement, the laying direction of the cooling water supply passage 16 is inclined by 45 degrees with respect to the facing direction of the lamp holder 6, so that the protruding lamp holder. Regardless of 6, cooling water can be supplied, and cooling water can be sent around the rod 1 from the rod portion casing 11 via the connection flow path 4a of the rod holder 4 for cooling.

[Other Embodiments] In the laser oscillation device according to the present invention, the following technique can be adopted instead of the one embodiment. a) The recess 19 is set to a shape other than a semicircle according to the cross sectional shape of the lamp holder 6. b) The rod 1 and the rod holder 4 are managed in a state in which they are attached to the rod end plate 15 and the excitation lamp 2 in a state in which they are attached to the lamp casing 12, and the fastening portion 13 ensures disassembly, assembly, and hermeticity. What is done c) The cooling water discharge structure is common with the supply structure. d) The excitation lamp is arranged on only one side of the rod, and the reflecting surface is composed of one ellipse. e) Providing a plurality of cooling water supply paths.

[0021]

According to the laser oscillating device of the first aspect, the following effects can be obtained. (1) The casing includes a rod casing, lamp casings arranged on both sides of the casing, and fasteners that integrate these, and the lamp casing includes a reflector main body and a reflector chamber externally fitted to the reflector main body. As a result, the casing, the rod, and the excitation lamp can be easily assembled. (2) By making the lamp casing into a fitting structure of the reflector main body and the reflector chamber, it is possible to easily achieve the formation of the reflection surface and the liquid tightness in addition to the improvement of the assembling property and the dismantling property. it can. According to the laser oscillation device of the second aspect, the following effect can be obtained in addition to the effect of the first aspect. Combined with the division of the rod casing and the lamp casing, the mounting space for the rod and the excitation lamp can be increased, and the workability at the time of assembly and division can be improved. According to the laser oscillation device of the third aspect, the following effects can be obtained in addition to the effects of the first or second aspect. By adopting a configuration in which only the lamp holder projects from the end of the casing, the overall size and weight can be reduced, and the lamp holder is independent of the rod casing, and the maintainability of the excitation lamp can be improved. According to the laser oscillation device of the fourth aspect, the following effects can be obtained in addition to the effects of the first, second or third aspect. By adopting the configuration in which the recess is arranged on the outer side of the rod casing, the lamp holder of the excitation lamp adjacent to the recess is positioned to reduce the rod-rod distance in the cascade arrangement, thereby lasing The startability at the time can be made good, and the laser output can be increased. According to the laser oscillation device of the fifth aspect, the following effects can be obtained in addition to the effects of the first, second, third or fourth aspect. By forming the cooling water supply passage in the rod end plate portion, the cooling water can be supplied around the rod without being interfered with by the lamp holder or the lamp casing. According to the laser oscillation device of the sixth aspect, the following effect is obtained in addition to the effect of the fifth aspect. The cooling water supply channel
By arranging along the direction inclining with respect to the rod and the excitation lamp, the cooling water supply path is located between the lamp holders even when the rods are arranged in a cascade arrangement, so that the cooling water can be supplied. Can be easily implemented. Further, the flow rate can be increased by providing a plurality of cooling water supplies in the upper, lower, left, and right directions.

[Brief description of drawings]

FIG. 1 is a partially sectional side view showing an embodiment of a laser oscillation device according to the present invention.

FIG. 2 is a front sectional view showing an embodiment of a laser oscillation device according to the present invention with a part of the description omitted.

FIG. 3 is a plan view showing a part of a lamp section casing of FIG. 2 with a part of the description omitted.

FIG. 4 is a side sectional view showing a portion of the rod end plate of FIG.

FIG. 5 is a plan sectional view of a portion shown in FIG.

FIG. 6 is a perspective view showing an embodiment of a laser oscillator according to the present invention in a cascade arrangement state.

FIG. 7 is a front sectional view showing a conventional example of a portion of a rod holder and a lamp holder in a laser oscillator.

[Explanation of symbols]

 1 Laser Light Generation Rod (Rod) 2 Excitation Lamp 3 Reflecting Tube (Reflecting Surface) 4 Rod Holder 4a Connection Channel 5 Electrode 6 Lamp Holder 10 Casing 11 Rod Part Casing 11a Step 11b Pin Hole 11c Screw Hole 12 Lamp Part Casing 12A Reflector body 12B Reflector chamber 12a Seal hole 12b End plate part 12c Lamp insertion hole 13 Fastening part 14 Cavity 15 Rod end plate 15a Holder insertion hole 16 Cooling water supply path 17 Seal groove 18 Seal member 19 Recess 20 Positioning pin

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Yutaka Kanazawa 3-15-1 Hoshu, Koto-ku, Tokyo Ishikawajima Harima Heavy Industries Co., Ltd. Toni Technical Center (72) Inventor Fumio Matsuzaka Yutaka, Koto-ku, Tokyo 3-15-1 Kyushu Ishikawajima Harima Heavy Industries Co., Ltd. Toji Technical Center (72) Inventor Koichiro Wazumi 3-15-15 Hoshu, Koshu-ku, Tokyo Ishikawajima Harima Heavy Industries Co., Ltd. Toji Technical Center

Claims (6)

[Claims] 1. A laser beam generating rod, an excitation lamp which is arranged on the side of the laser beam generating rod and irradiates excitation light, a laser beam generating rod and an excitation lamp are housed, and a reflection surface is formed on the inner surface. A laser oscillation device having a casing, wherein the casing surrounds a rod for laser light generation, a lamp casing arranged laterally of the rod casing to surround an excitation lamp, a rod casing, and The lamp unit casing comprises a fastener that integrates the lamp unit casing, and the lamp unit casing includes a reflector main body having a reflection surface on an inner surface thereof, and a reflector chamber externally fitted to the reflector main body in a liquid-tight state. Laser oscillator. 2. The laser oscillating device according to claim 1, wherein the reflecting surface is formed on the inner wall of the cavity having a cross section in which two ellipses are overlapped in the major axis direction. 3. The laser oscillating device according to claim 1, wherein a lamp holder surrounding an electrode of the excitation lamp is provided in a protruding state at an end of the lamp casing. 4. The laser oscillation device according to claim 1, wherein a recessed portion in a state of being close to the laser light generating rod is provided on the outer side of the rod casing. 5. A rod end plate is attached to an end portion of the rod casing in a liquid-tight state, and a cooling water supply passage for supplying cooling water around the laser light generating rod is formed in the rod end plate. The laser oscillation device according to claim 1, 2, 3, or 4. 6. The laser oscillating device according to claim 5, wherein the cooling water supply passage is arranged along a direction inclined with respect to the facing direction of the laser light generating rod and the excitation lamp.