JPH05245158A - Laser probe - Google Patents

Abstract

PURPOSE:To prevent the deterioration in the quality occurring in a chemical reaction and to eliminate the need for costly gold plating by providing a hollow tube made of sapphire on the laser exist part of the laser probe constituted by building a silver halide optical fiber for guiding a CO2 laser therein. CONSTITUTION:The hollow tube 13 made of the sapphire is mounted to the laser exit part of the laser probe constituted by fitting a fluororesin tube 12 onto the outer peripheral part of silver halide optical fiber 11 consisting of the silver chloride or silver bromide in a clearance for flow of a cooling gas 14 and protecting an optical fiber 11. The inside diameter of the hollow tube 13 is formed slightly larger than the outside diameter of the optical fiber 11 and the cooling gas is passed through the clearance between both 11 and 13, by which the melting by the overheating of the optical fiber 11 is prevented and the adhesion of the splashes to the end face of the optical fiber 11 is prevented. The optical fiber 11 and the hollow tube 13 are free from the deterioration in the quality occurring in the chemical reaction in site of direct contact with each other, and therefore the number of parts necessary for maintaining the quality is reduced.

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 power transmission using an optical fiber capable of guiding a carbon dioxide laser.

[0002]

2. Description of the Related Art As a conventional laser probe for carbon dioxide gas laser, one shown in FIG. 4 is known. In the following, referring to FIG. 4, 1 is a silver halide optical fiber made of silver chloride / silver bromide, 2 is a gold-coated metal chip, and one end 2a of the metal chip 2 is caulked to be deformed. The optical fiber 1 is fixed. Generally, silver halide optical fibers are precious metals (gold, platinum, tantalum, titanium, etc.)
When it comes into contact with a general structural metal (iron-based, copper-based, aluminum-based, etc.) that does not exist, a chemical reaction is likely to occur, and in order to prevent this, in general, the inner surface of the metal chip 2 is often coated with gold. Reference numeral 3 denotes a window (optical window) that protects the emission end of the optical fiber 1 and is made of diamond. A window holder 4 holds the window 3 at its front end, and its rear end is externally fitted and pressure-bonded to the gold-coated metal chip 2 to be fixed. 5 is a fluororesin tube for protection. 6
Is a joint for fixing the gold-coated metal chip 2 and the tube 5 by pressure fitting, and positions the optical fiber 1 at the center of the tube 5. Reference numeral 7 denotes a metal tip portion of the laser probe whose rear end is fixed to the joint 6 by external fitting pressure bonding.

When a normal probe is too thick to be used, as shown in FIG. 5, a hollow waveguide 8 made of a metal tube having an inner surface polished and plated with gold is attached to the tip of the tip metal portion 7. The composition is devised.

[0004]

However, since diamond is used as the window material in the above conventional structure, it is very expensive. Further, the silver halide optical fiber 1 is extremely reluctant to come into contact with general structural metals other than noble metals, which complicates the structure. Furthermore, even when using gold plating, where the reaction due to contact has no practical problems,
Sufficient quality control is required and there are problems in terms of man-hours and price. For this reason, it is a major obstacle to its widespread use.

In particular, when it is used for a medical laser treatment device, it is desired from the hygienic point of view that the tip portion has a disposable structure as much as possible, but it is impossible with a conventional carbon dioxide laser probe.

The present invention has been made to solve the above conventional problems, and an object thereof is to provide an inexpensive and sanitary laser probe for a carbon dioxide gas laser.

[0007]

In order to solve this problem, the present invention provides a laser probe incorporating a silver halide optical fiber made of silver chloride / silver bromide for guiding a carbon dioxide laser, which emits laser light. A hollow tube made of sapphire is provided in the part. Further, the present invention is a laser probe incorporating a thallium halide optical fiber composed of thallium iodide and thallium bromide that guides a carbon dioxide laser, in which a hollow tube made of sapphire is provided in the laser emitting portion. ..

[0008]

With this structure, even if the highly reactive optical fiber and the sapphire hollow tube come into direct contact with each other, the quality deterioration due to the chemical reaction is eliminated. Therefore, an expensive window material and gold plating can be omitted, and a simple configuration with a small number of parts can be realized.

[0009]

Embodiments of the present invention will be described below with reference to the drawings. First, in FIG. 1 showing the first embodiment, 11
Is a silver halide optical fiber consisting of silver chloride and silver bromide, 12
Is a tube made of fluororesin that protects the silver halide optical fiber 11, the tip of this tube 12 and the tip of the optical fiber 11 are aligned, and even if this tube 12 directly contacts the optical fiber 11, it chemically reacts. Never. 13 is a hollow tube made of sapphire, which is fitted and fixed inside the tip of the tube 12. The inner diameter of the hollow tube 13 made of sapphire is slightly larger than the outer diameter of the silver halide optical fiber 11. Reference numeral 14 denotes a cooling gas flowing between the tube 12 and the silver halide optical fiber 11, and the cooling gas 14 flows through the gap between the silver halide optical fiber 11 and the sapphire hollow tube 13 to generate a silver halide optical fiber. The melting of the fiber 11 due to overheating is prevented. Further, the cooling gas 14 also plays a role of preventing the scattered matter from adhering to the end surface of the silver halide optical fiber 11.

To guide light in the hollow tube 13, the hollow tube 13
It is necessary to totally reflect on the inner surface, and the refractive index of the material needs to be less than 1. Generally, such a substance does not exist, but considering the complex refractive index, it is possible to make the value smaller than 1 for light of a specific wavelength. Figure 3
Figure 2 shows the relationship between the wavelength of the hollow tube 13 made of sia and the power attenuation factor during light guide. The wavelength of the carbon dioxide laser is 10.6 μm.
Is about 3 dB / m, which is sufficiently practical as a carbon dioxide laser waveguide.

Next, a second embodiment of the present invention will be described with reference to FIG. In the figure, 15 is a hollow tube holder, which is press-fitted and fixed to the tip of a fluororesin tube 12 for protecting the silver halide optical fiber 11. 16 is a hollow tube made of sapphire fixed to the end of the hollow tube holder 15, and by allowing the hollow tube 16 to be detachable from the fluororesin tube 12 integrally with the hollow tube holder 15, in terms of hygiene. From the above points, a disposable form desired in a medical treatment device becomes possible, and cleaning of stains on the hollow tube 16 due to scattered substances from the tissue due to laser irradiation and replacement due to deterioration of life becomes easy. Even if the hollow tube 16 can be detached from the hollow tube holder 15, the same effect can be obtained.

In the above embodiments, the silver halide optical fiber of silver chloride / silver bromide for carbon dioxide laser was used as the optical fiber, but the thallium iodide / thallium bromide optical fiber is used. May be used.

[0013]

As described above, according to the present invention, even if the highly reactive optical fiber directly contacts the hollow tube made of sapphire, the quality deterioration due to the chemical reaction is eliminated. Therefore, an expensive window material and gold plating can be omitted, and a simple structure with a small number of parts can be provided, and an inexpensive laser probe for a carbon dioxide laser can be provided.

[Brief description of drawings]

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

FIG. 2 is a sectional view of a laser probe emission end of a carbon dioxide gas laser according to a second embodiment of the present invention.

FIG. 3 is a characteristic diagram of a sapphire hollow tube.

FIG. 4 is a cross-sectional view of a laser probe emitting end portion for a carbon dioxide laser in a conventional example.

FIG. 5 is a cross-sectional view of a laser probe emitting end portion for a carbon dioxide gas laser in another conventional example.

[Explanation of symbols]

 11 Silver halide optical fiber 12 Tube 13 Sapphire hollow tube 14 Cooling gas 15 Hollow tube holder 16 Sapphire hollow tube

Claims (2)

[Claims] 1. A laser probe incorporating a silver halide optical fiber made of silver chloride / silver bromide for guiding a carbon dioxide laser, characterized in that a hollow tube made of sapphire is provided at the laser emitting portion. Laser probe to do. 2. A laser probe incorporating a thallium halide optical fiber composed of thallium iodide and thallium bromide that guides a carbon dioxide laser, wherein a hollow tube made of sapphire is provided in the laser emitting portion. And laser probe.