JPH0592012A - Laser probe - Google Patents

Abstract

PURPOSE:To decrease the heat generation in the metallic part at the front end of the laser probe for a carbon dioxide laser and to increase an output. CONSTITUTION:This laser probe is constituted by fixing an optical fiber 1 with a caulking part 8 of a metallic chip 2, forming a window 3 for protecting the output end of the optical fiber 1 of SrF2 and holding this window 3 by means of a window holder 4 to be press-fitted and fixed to the metallic chip 2. The refractive index at 10.6mum is thereby made lower than the refractive index of the conventional window made of diamond and reflected light is decreased. The generation of the heat is thus lessened and the output of the laser probe is increased.

Description

Detailed Description of the Invention

[0001]

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

[0002]

2. Description of the Related Art A conventional laser probe for a carbon dioxide gas laser will be described below.

As shown in FIG. 2, a silver halide optical fiber 1 made of silver chloride / silver bromide is used to crimp a metal chip 2 to a crimped portion 8.
It is fixed at. A diamond window 9 that protects the emitting end of the optical fiber 1 is held by a window holder 4 and is press-fitted and fixed to the metal chip 2. Reference numeral 5 in the drawing denotes a joint for fixing the metal tip 2 by press fitting and also fixing the outer tube Teflon tube 6 to determine the positional relationship between the optical fiber 1 and the outer tube Teflon tube 6. Reference numeral 7 denotes a tip metal portion which is fixed to the joint 5 by press fitting and serves as a tip of the laser probe.

[0004]

However, in the above-mentioned conventional structure, since diamond is used as the material of the window 9, there is a problem that the cost becomes high.
The refractive index at a wavelength of 10.6 μm is 2.41 and reflection of about 30% occurs, which causes the tip metal part to generate heat, resulting in a decrease in power resistance.

The present invention solves the above-mentioned conventional problems, and an object of the present invention is to provide a laser probe in which the amount of reflected light is small and the heat generated at the tip metal portion is reduced, and the output is increased.

[0006]

To achieve this object, the laser probe of the present invention is provided with a SrF ₂ window or a BaF ₂ window formed by sintering, instead of the diamond window. It is a thing.

[0007]

With this structure, the refractive index at 10.6 μm is lower than that of diamond, and the reflected light is reduced.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings.

In FIG. 1 showing an embodiment of the present invention, the same parts as those in the conventional example are designated by the same reference numerals and the description thereof will be omitted.

As shown in FIG. 1, the window 3 for protecting the emitting end of the optical fiber 1 is made of SrF ₂ , and the window 3 is held by a window holder 4.

With the above structure, the material cost of the window 3 made of SrF ₂ is about 1/10 of that of the conventional window 9 made of diamond, which is inexpensive. Also, 10.
The refractive index at 6 μm is lower than that of diamond, so that the reflected light is reduced, the factor of heat generation can be reduced, and the output of the laser probe can be increased.

This SrF ₂ is a single crystal of BaF ₂ or C.
It has better heat shock resistance than aF ₂ and when laser input
It is less likely to crack due to thermal expansion, is non-toxic, has little deliquescent, and can be used for the window of a medical laser probe.

Further, single crystal BaF ₂ has poor heat shock resistance and cracks due to thermal expansion, but BaF ₂ polycrystallized by sintering has improved heat shock resistance and is nontoxic and less deliquescent. Can also be used for the window 3 of the medical laser probe.

In the present embodiment, the optical fiber 1 is a silver halide / silver bromide silver halide optical fiber 1 for a carbon dioxide laser, but it has been described. The optical fiber 1 may be used.

[0015]

As is apparent from the above description of the embodiments, the present invention has a structure provided with a window made of SrF ₂ or polycrystalline BaF ₂ to reduce reflected light and reduce heat generation at the tip metal portion. It is possible to realize an excellent laser probe with increased output.

[Brief description of drawings]

FIG. 1 is a schematic sectional view of an emission end of a laser probe according to an embodiment of the present invention.

FIG. 2 is a schematic cross-sectional view of the emitting end of a conventional laser probe.

[Explanation of symbols]

1 Optical fiber 3 SrF ₂ made window 4 Wind holder 7 Tip metal part

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁵ Identification code Office reference number FI technical display location H01S 3/034 3/08

Claims (2)

[Claims] 1. A laser probe incorporating an optical fiber for passing a carbon dioxide laser, wherein the laser emitting portion is SrF ₂
Laser probe with a metal window. 2. The laser probe according to claim 1, further comprising a polycrystalline BaF ₂ window formed by sintering instead of the SrF ₂ window in the laser emitting portion.