JP2002131588A - High output pulse laser irradiator - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a high output pulse laser irradiator which easily and surely transmits high output pulse laser beams to an arbitray position and in which the handling is superior. SOLUTION: The irradiator irradiates high output pulse laser light beams to an object to be irradiated. The irradiator is provided with a high output pulse laser oscillator 1, a laser adjusting device 3 which adjusts high output pulse laser light beams 2 from the oscillator 1, a handle type fiber 8 in which the beams 2 from the device 3 are made incident on an incident end 8a and is transmitted to a laser irradiating head 5 connected to an emitting end 8b located at the other end of the fiber 8 and a fiber cooling device 24 which at least cools the end 8a of the fiber 8.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a high-power pulsed laser irradiation apparatus.

[0002]

2. Description of the Related Art Conventionally, an optical fiber has been used as a means for transmitting laser light or the like emitted from a laser oscillator. Generally, an optical fiber has a configuration in which a low-refractive-index cladding is coated on the outer periphery of a core made of quartz or the like having a uniform refractive index, and laser light from a laser oscillator is applied from the incident end of the optical fiber to the core. The light is incident, propagates inside the core while repeating total reflection, and is emitted from the emission end.

On the other hand, in recent years, use of a high-power pulse laser has been studied in nuclear facilities in order to decontaminate containers and equipment in a highly radioactive atmosphere that is inaccessible to humans.

As an irradiation apparatus using such a high-output pulse laser, as shown in FIG. 3, a high-output pulse laser oscillator 1 and a caliber of a high-output pulse laser 2 from the high-output pulse laser oscillator 1 are used. And a laser adjusting device 3 including various lenses for adjusting an incident angle and the like.
Further, the high-power pulse laser 2 from the laser adjusting device 3
Is reflected by the adjustment mirror 4 so that the laser irradiation head 5
To emit light from the laser irradiation head 5 toward the irradiation target 6.

In the above-described high-power pulse laser irradiation device, the high-power pulse laser 2 is irradiated onto the surface of the irradiation target 6 by adjusting the angle of the adjustment mirror 4 and simultaneously moving the laser irradiation head 5. To irradiate the surface.

[0006]

However, in the high-power pulse laser irradiation apparatus shown in FIG. 3, the movement adjustment of the high-power pulse laser 2 for irradiating the irradiation target 6 is performed by adjusting the angle of the adjustment mirror 4 and the laser. Since the movement of the irradiation head 5 needs to be performed in conjunction with the movement, there is a problem that the movement adjustment for the irradiation is complicated and the fine adjustment is difficult. In addition, since the irradiation of the predetermined range is performed by changing the angle of the adjustment mirror 4, the irradiation angle of the high-power pulse laser 2 to the irradiation target 6 changes, and the distance between the laser irradiation head 5 and the irradiation target 6 changes. There is a problem in that the distance changes, which makes uniform irradiation difficult. Further, for example, there is a problem that it is extremely difficult to uniformly irradiate the irradiation target 6 having a curved surface shape.

Therefore, in the case of performing decontamination work in a highly radioactive atmosphere in nuclear facilities, it is necessary to perform remote adjustment using a robot arm or the like, which makes such work extremely difficult. There is.

On the other hand, in order to cope with the above problem, a high-power pulse is used by using an optical fiber having a single-line structure in which an incident end is connected to a laser adjusting device and the other end is connected to a laser irradiation head. It is conceivable to transmit the laser to a laser irradiation head. As described above, if a high-output pulse laser can be transmitted using an optical fiber, the laser irradiation head can freely move, thereby facilitating the irradiation operation and increasing the efficiency.

However, when transmitting the high-power pulse laser through the optical fiber having the single-line structure as described above, the optical fiber is heated at the incident end of the optical fiber or at the bent portion of the optical fiber. 200 to 30
The temperature will be around 0 ° C, and if used for a long time due to this high temperature, the optical fiber made of quartz will be broken and broken,
Further, there is a problem that the adhesive surface at the incident end of the optical fiber is stained (discolored to black), so that the laser transmission efficiency is greatly reduced.

The present invention has been made in view of the above-mentioned circumstances, and enables a high-output pulse laser to be easily and reliably transmitted to an arbitrary position. It is an object of the present invention to provide a high-power pulse laser irradiation device.

[0011]

SUMMARY OF THE INVENTION The present invention relates to a high-power pulse laser irradiation apparatus for irradiating a high-power pulse laser to an object to be irradiated, comprising: a high-power pulse laser oscillator; A laser adjusting device that adjusts the high-power pulse laser; a bundled optical fiber that receives the high-power pulse laser from the laser adjusting device from an incident end and transmits the laser to a laser irradiation head connected to the other end of the laser; And a fiber cooling device for cooling at least the input end of the bundle type optical fiber.

In the above means, the fiber cooling device comprises:
A cooling jacket provided on the outer periphery of the bundle type optical fiber may be used.

According to the present invention, the high-power pulse laser emitted from the high-power pulse laser oscillator and adjusted by the laser adjusting device is transmitted to the laser irradiation head via the bundle type optical fiber. By dispersing the output of the high-power pulse laser incident on each strand of the optical fiber, the load per strand can be reduced, thereby reducing the problem that each strand is broken and disconnected. Furthermore, since a fiber cooling device for cooling at least the incident end of the bundle type optical fiber is provided, a problem that the bundle type optical fiber is broken by high temperature can be surely prevented.

Therefore, the high-power pulse laser can be easily and reliably transmitted to an arbitrary position by the bundle type optical fiber, and the irradiation target can be irradiated from an arbitrary direction. An efficient irradiation operation can be performed.

Further, by configuring the fiber cooling device with a cooling jacket provided on the outer periphery of the bundle type optical fiber, the bundle type optical fiber can be effectively cooled by a small fiber cooling device.

[0016]

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

FIG. 1 shows an embodiment of a high-output pulse laser irradiation apparatus according to the present invention. In this high-output pulse laser irradiation apparatus, a high-output pulse laser 2 from a high-output pulse laser oscillator 1 is used. After the aperture and incident angle of the high-power pulse laser 2 are adjusted by the laser adjusting device 3, the laser beam is guided to the incident device 7.

A bundle-type optical fiber for inputting the high-power pulse laser 2 from the laser adjusting device 3 from the input end 8a to the input device 7 and transmitting the pulsed laser 2 to the laser irradiation head 5 connected to the output end 8b at the other end. 8 are connected.

As shown in FIG. 2, the bundle type optical fiber 8 is formed by bundling, for example, around 320 strands 9 of, for example, about 230 μm, each of which is formed by covering the outer periphery of a core (not shown) with a clad, and covering the outer periphery with a coating 10. It has the following configuration. A fixed tube 11 is integrally fixed to the outer periphery of the incident end 8a of the bundle type optical fiber 8.

The bundle type optical fiber 8 has a fixed tube 11 inserted into a mounting opening 13 formed in a fixing member 12 of the incident device 7 and fixed with a fixing bolt 14. Further, the high-power pulse laser 2 condensed at a required incident angle by the condenser lens 15 provided in the incident device 7 is incident on the end face 16 of the incident end 8a of the bundle type optical fiber 8. I have. The end face 16 of each of the input end 8a and the output end 8b of the bundle type optical fiber 8 is provided with an anti-reflection coating.

Further, in FIG. 2, a cooling jacket 17 is formed on the fixing member 12 of the incident device 7 so as to surround the outer periphery of the fixed tube 11, and a cooling fluid supply port 18 is provided in the cooling jacket 17. A fiber cooling device 20 configured to cool the incident end 8a of the bundle-type optical fiber 8 by supplying a cooling fluid such as a liquid such as cooling water or a gas such as cooling air from the outlet and discharging the cooling fluid from the outlet 19 is provided. Have been.

FIG. 2 shows an example in which the fiber cooling device 20 is formed only on the outer periphery of the incident end 8a of the bundle type optical fiber 8, but as shown by a two-dot chain line in FIG. A cooling tube 21 is provided over the entire length of the cooling tube 21, and a cooling fluid is supplied from a cooling fluid supply port 22 at one end of the cooling tube 21 and discharged from a discharge port 23 at the other end of the bundle type optical fiber. A fiber cooling device 24 configured to cool the entire length of the fiber 8 may be configured.

Next, the operation of the above embodiment will be described.

The high-power pulse laser 2 emitted from the high-power pulse laser oscillator 1 shown in FIG. 1 is guided to the injection device 7 after the laser adjusting device 3 adjusts the aperture and the incident angle of the high-power pulse laser 2. Condensing lens 1 shown in FIG.
5 to the end face 16 of the incident end 8a of the bundle type optical fiber 8
Is incident on.

At this time, the high-power pulse laser 2 is dispersedly incident on each strand 9 of the bundle type optical fiber 8, and the high-output pulse laser 2 incident on each strand 9 transmits each strand 9. Is irradiated from the laser irradiation head 5 and irradiated.
Is irradiated.

At this time, since the high-power pulse laser 2 is transmitted to the laser irradiation head 5 via the bundle-type optical fiber 8, the high-power pulse laser 2 incident on each strand 9 of the bundle-type optical fiber 8 is transmitted. By dispersing the output of the pulse laser 2, the load per each wire 9 is reduced,
This can reduce the problem that each element wire 9 is broken and disconnected.

Further, as shown in FIG. 2, a fiber cooling device 2 for cooling the input end 8a of the bundle type optical fiber 8 is provided.
0, or as shown in FIG.
By providing the fiber cooling device 24 for cooling the entire length of the optical fiber, it is possible to reliably prevent a problem that the bundle type optical fiber 8 is broken by high temperature.

At this time, the fiber cooling devices 20 and 24
Is constituted by the cooling jacket 17 provided on the outer periphery of the bundle type optical fiber 8, the bundle type optical fiber 8 can be effectively cooled by the small fiber cooling devices 20 and 24.

As described above, since the high-power pulse laser 2 can be transmitted through the bundle-type optical fiber 8, the high-power pulse laser 2 can be easily and reliably placed at an arbitrary position.
Can be transmitted, so that the irradiation target 6 can be irradiated from any direction, so that the handleability is improved and efficient irradiation is possible.

The high-output pulsed laser irradiation apparatus of the present invention is not limited to the above-described embodiment, but various modifications can be made without departing from the scope of the present invention. .

[0031]

As described above, according to the high-power pulse laser irradiation apparatus of the present invention, the high-power pulse laser emitted from the high-power pulse laser oscillator and adjusted by the laser adjusting device is supplied to the bundle type optical fiber. The laser beam is transmitted to the laser irradiation head through the optical fiber, so that the output of the high-power pulse laser incident on each strand of the bundle-type optical fiber can be dispersed to reduce the load per strand, thereby reducing each element. This has the effect of reducing the problem that the wire is broken and disconnected. Further, since a fiber cooling device for cooling at least the incident end of the bundle type optical fiber is provided, there is an effect that the problem that the bundle type optical fiber is broken by high temperature can be surely prevented.

Therefore, the high-power pulse laser can be easily and reliably transmitted to an arbitrary position by the bundle type optical fiber, and the irradiation target can be irradiated from an arbitrary direction, so that the handling property is improved. This has the effect of enabling efficient irradiation work.

In addition, since the fiber cooling device is constituted by a cooling jacket provided on the outer periphery of the bundle type optical fiber, there is an effect that the bundle type optical fiber can be effectively cooled by a small fiber cooling device.

[Brief description of the drawings]

FIG. 1 is a conceptual diagram showing an example of an embodiment of a high-output pulsed laser irradiation apparatus according to the present invention.

FIG. 2 is a detailed sectional view of a portion II in FIG.

FIG. 3 is a conceptual diagram showing an example of a conventional high-output pulsed laser irradiation device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 High output pulse laser oscillator 2 High output pulse laser 3 Laser adjustment device 5 Laser irradiation head 6 Irradiation object 8 Bundle type optical fiber 8a Incident end 8b Emitting end 17 Cooling jacket 20 Fiber cooling device 24 Fiber cooling device

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 2H037 AA04 BA06 CA02 DA38 2H046 AA03 AA42 AD00 5F072 KK30 MM08 SS06 YY20

Claims (2)

[Claims] 1. A high-power pulse laser irradiation device for irradiating a high-power pulse laser to an irradiation target, comprising: a high-power pulse laser oscillator; and a laser for adjusting the high-power pulse laser from the high-power pulse laser oscillator. An adjusting device;
A bundle-type optical fiber that emits a high-power pulse laser from the laser adjusting device from an incident end and transmits it to a laser irradiation head connected to the other end of the optical fiber; and a fiber that cools at least the incident end of the bundle-type optical fiber A high-power pulsed laser irradiation device comprising: a cooling device. 2. The high-power pulsed laser irradiation apparatus according to claim 1, wherein the fiber cooling device is a cooling jacket provided on the outer periphery of the bundle type optical fiber.