JPS6070413A - Guide light method - Google Patents

Abstract

PURPOSE:To superpose visible light on invisible CO2 laser light and to use the superposed light for indicating the position to be irradiated by forming an optical waveguide for visible light into a tube and passing an IR fiber therein. CONSTITUTION:An IR fiber 3 is passed into a tube 6 consisting of a material which allows transmission of visible light, for example, PMMA (polymethyl methacrylate), etc. The PMMA tube is slit up to the mid-way and the IR fiber is taken out through the slit and is used as an incident end for CO2 laser light. The part 70 of the tube is distributed with the refractive index higher than the refractive index on the inside 71 and outside 72 thereof. The end of the tube on the side slit for the purpose of incidence of visible light is thermally worked to form the construction which is not tubular but circular columnar in section and to which light is made incident effectively. Visible light is thus always focused at one point on the focal plane and is made annular in the parts except the focal plane, by which the presence of IR light in said ring is distinctly indicated. Easy assembly is made possible simply by inserting the IR fiber in the case of manufacturing the IR fiber with indicating light.

Description

Detailed Description of the Invention (Technical Field) The present invention is applicable to cases in which a C02 laser beam is passed through an infrared fiber and irradiated onto an object (for example, in laser surgery).
This invention relates to an improvement in the method of superimposing visible light on invisible C02 laser light and using it to indicate the irradiation position.

(Prior art and its problems) When irradiating a target with laser light using an infrared fiber made of a material that transmits CO2 laser light, CO2
The laser beam 1 has a wavelength of 1056 μm, and the substance that transmits it does not transmit visible light. Therefore, as shown in FIG. A method is adopted in which visible light is passed through several fibers along the periphery of the fiber optics 3 and condensed by a lens 5. Figures 2(a) and (b) are A of Figure 1, respectively.
- It is a sectional view of AlB-B. In this case, several rays 4
．． 3A and 3B, the focal point of the lens is one point, but there are several points of light outside the focal point, which is a disadvantage. In addition, if the end faces of several fibers are not aligned well, there is a possibility that they will not be focused at a single point.

(Structure of the Invention) In order to improve such drawbacks, the present invention is characterized in that the light guide path for visible light is formed into a tube, and an infrared fiber is passed through the tube. As shown in Figure 4, the infrared fiber 4 is passed through a tube made of a substance that transmits visible light, such as PMMA (polymethyl methacrylate), and the PMMA tube is cut halfway and the infrared fiber is taken out. , C
This is the incident end of the O2 laser beam. At this time, C-C in Figure 4.
The cross section of is shown in FIG. 5(b). In order to allow visible light to enter, the cut end is thermally processed so that the cross section is not a tube but a cylinder as shown in Figure 5(b) corresponding to D-D in Figure 4. The structure is as follows. In this case, Figure 6 (
As shown in a) and Figure 6(b), visible light always forms a single point at the focal plane, and forms a ring outside the focal plane, and it can be clearly shown that infrared light exists within this ring. . As shown in FIG. 7, the structure of the PMMA tube used for this purpose is that a portion 70 of the tube has a higher refractive index distribution than its inner side 71 and outer side 72, allowing light to be transmitted without escaping.

(Effects of the Invention) According to the present invention, a ring-shaped indicator light can be obtained, and when making an infrared fiber with an indicator light, it can be easily assembled because it is simply inserted.

[Brief explanation of the drawing]

FIG. 1 is a diagram showing the structure of a conventional infrared fiber with an indicator light, and FIGS. 2(a) and 2(b) are taken along line A-A in FIG. 1, respectively. FIG. FIG. 4 is a diagram showing the structure of an infrared fiber with an indicator light of the present invention,
FIG. 5(aHb) is a diagram showing the cross-sectional structure of CC and D-D in FIG. FIG. FIG. 7 is a diagram showing the structure of the visible leading light path. ]... C02 laser beam 2, He-Ne laser beam 3, infrared fiber 4, visible light fiber 5, lens 6, visible light tube 70, tube 71, inner part of tube 72,・Outer part of the tube

Claims (1)

[Claims] (1) By inserting a light guide path that transmits invisible light into a tube made of a material that transmits visible light, and passing visible light through the tube wall, the light guide path that passes through the light guide path inserted into the tube is Guide light method used as visible light instruction light.