JP2922023B2 - Laser probe - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a laser probe for a carbon dioxide laser incorporating an optical fiber.

[0002]

2. Description of the Related Art Conventionally, a laser probe for a carbon dioxide laser has, for example, a structure as shown in FIG. FIG.
In the figure, 1 is a silver halide optical fiber made of silver chloride and silver bromide. 3 is a diamond window for protecting the output end of the optical fiber 1,
Reference numeral 4 denotes a diamond window, which holds the diamond window 3.
Window holder for press-fitting and fixing 5
And a joint for fixing the optical fiber 1 and the outer tube fluororesin tube 6 by press-fitting and fixing to the outer tube fluororesin tube 6 at the same time. It is a metal part.

[0003]

However, in the above-mentioned conventional structure, the structure is complicated, the number of parts is large, and the structure is expensive.

In order to protect the end face of the fiber from flying objects, a diamond window is attached to the tip of the probe. However, due to the difference in the refractive index between the diamond window and the space inside the probe, laser light is reflected by the diamond window. Therefore, there is a problem in that heat is generated in the tip metal portion, and high power resistance cannot be obtained.

An object of the present invention is to provide a laser probe for a carbon dioxide laser which has a simple structure, is inexpensive in terms of cost, and has high power durability.

In order to achieve the above object, a laser probe according to the present invention transmits laser light, guides the emitted laser light to a laser irradiation direction, an optical fiber having an open end and a laser light emitting portion, and A hollow waveguide having an open end, and the laser light end face of the fiber is located in the hollow waveguide.

[0007]

According to the above-described means, the structure of the laser probe emitting section itself is simple and the cost is low. Also, can eliminate the cause of heat generation without the reflected light is generated no diamond window, cooling because that can safely gas into the hollow waveguide is performed efficiently, with the power resistance can be significantly improved, this Tip while having effect
The size of the part can be prevented from increasing.

[0008]

An embodiment of the present invention will be described below with reference to FIG. In FIG. 1, the same members as those in FIG. 2 are denoted by the same reference numerals, and different portions will be described. In FIG.
Reference numeral 1 denotes a silver halide optical fiber made of silver chloride or silver bromide, which is housed in a phosphor bronze tube 8. The tip of the optical fiber 1 is housed in a hollow waveguide 9 in which a germanium thin film 11 is provided on the inner surface of a nickel tube 10, and the phosphor bronze tube 8 and the hollow waveguide 9 are bonded and fixed. The cooling gas 12 flows from the gap between the phosphor bronze tube 8 and the optical fiber 1 through the gap between the hollow waveguide 9 and the optical fiber 1. Reference numeral 13 denotes a laser beam.

[0009] The distal end of the hollow waveguide 9 is a light emitting portion 14 which is an opening surface. The light emitting section 14 has a certain length from the tip of the optical fiber 1, and the light emitting section 14 is formed as an opening surface continuous with the hollow waveguide. In this embodiment, the optical fiber 1 is not fixed to the hollow waveguide 9, and the optical fiber 1 moves back and forth in the hollow waveguide 9 due to the bending of the phosphor bronze tube 8, but has moved to the tip end. Even in this case, the other end of the phosphor bronze tube 8 is fixed inside the hollow waveguide 9 so as to keep a distance of about 2 mm from the opening surface of the light emitting portion 14 which is the tip of the hollow waveguide 9. In this state, the cooling gas is reduced to 0.
If the flow rate is 51 / min or more, the scattered matter does not enter the hollow waveguide 9 during laser irradiation, and the scattered matter does not adhere to the tip of the optical fiber.

With the above structure, the influence of flying objects can be eliminated, so that it is not necessary to install a diamond window at the tip of the laser probe, so that the cause of heat generation due to reflected light can be eliminated. Further, the cooling gas 1 is provided in the hollow waveguide 9.
Cooling can be performed effectively because of the structure that allows 2 to flow. And
The structure itself is simple, the number of parts is small, and it is inexpensive.

The inner surface of the hollow waveguide 9 is polished,
Similar effects can be obtained with a metal tube or a sapphire tube having a surface roughness of 0.7 μm or less and a gold plating on the surface.

Although silver chloride and silver bromide silver halide optical fibers for a carbon dioxide laser have been described as optical fibers, thallium iodide and thallium bromide thallium halide optical fibers may be used.

Although a phosphor bronze tube has been described as an example of a tube for accommodating an optical fiber, a tube made of titanium or gold, or a resin tube such as a metal tube or a fluororesin tube whose inner surface is plated with gold may be used.

[0014]

As is apparent from the above description, the laser probe of the present invention has a simple emission part structure, has a small number of parts, and is inexpensive. Also, there is no need to provide a diamond window at the tip of the laser probe,
Therefore, the cause of the heat generated by the reflected light can be removed, cooling can be performed efficiently, and the power resistance is significantly improved .
While having this effect, it is possible to prevent enlargement of the tip
it can.

[Brief description of the drawings]

FIG. 1 is a sectional view of an emission end of a laser probe for a carbon dioxide gas laser according to an embodiment of the present invention.

FIG. 2 is a sectional view of an emission end of a conventional laser probe for a carbon dioxide laser.

[Explanation of symbols]

 1 optical fiber 9 hollow waveguide

Claims (3)

(57) [Claims] [Claim 1] and through the laser beam, and opening the tip laser
-The optical fiber used as the light emitting part and the emitted laser
Light is guided in the direction of laser irradiation, and the tip is opened
A hollow waveguide, and the fiber laser end face is
A laser probe characterized by being located in an empty waveguide . 2. The laser probe according to claim 1, wherein the optical fiber is movable within the hollow waveguide, and the tip of the optical fiber does not protrude from the inside of the hollow waveguide by a predetermined length. 3. The laser probe according to claim 1, wherein the optical fiber is a halide-based material made of silver chloride or silver bromide, and the hollow waveguide has a nickel tube provided with a germanium layer on an inner surface thereof.