JPS60108806A - Optical fiber - Google Patents

Abstract

PURPOSE:To guide visible rays also coaxially with a working light by inserting an optical fiber core, which guides the working light, into a metallic tube to suppress heating by effects of reflection, heat conduction, or the like of the metal and forming a visible-ray guide path on the outside circumference of the metallic tube. CONSTITUTION:The CO2 laser light transmitted by an optical fiber core 1 is condensed by the second condenser lens 8 to perform the work. Even if the CO2 laser light is leaked a little to the outside from the outside circumference of the optical fiber core 1 by phenomena of scattering or the like on the way of transmission in the optical fiber core 1, heating is suppressed by actions of reflection, heat conduction, etc. of the metallic surface because the optical fiber core 1 is stored in a metallic tube 2. Meanwhile, the He-Ne laser light of visible rays emitted from an He-Ne laser oscillator 9 is converted to an annular beam by a conical prism 10. This laser light is reflected on a Ge mirror 7 and is made incident on a visible-ray guide path 4 and is condensed by the condenser lens 8 to indicate the condensation point of the working light.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to an optical fiber for power transmission used in laser processing machines, laser scalpels, and the like.

Conventional Structure and Problems In recent years, attempts have been made to condense work light such as infrared power laser light such as a C02 laser using all lenses to process metals, ceramics, etc., incise living bodies, etc. Conventionally, mirror-articulated light guide paths have been used to guide these laser beams to all working areas, but they are difficult to operate, and optical fibers are now being used instead.

Since infrared laser light is invisible light, workers cannot directly see the focal point. Therefore, it is necessary to illuminate and display the position of the focal point with other visible light, such as He -, -Ne laser light, etc.

However, the material of the optical fiber that can guide a power laser such as a CO2 laser is HLl, and in many cases cannot necessarily transmit visible light at the same time. For example, optical fibers made of halides such as KH2-5 are considered to be the most promising light guide for CO2 laser light with a wavelength of 10.6 μm, but they cannot transmit visible light at all, so conventionally visible light It was necessary to install a separate quartz fiber to guide the flow. It is also possible to directly coat the outer periphery of the optical fiber that guides working light such as infrared power laser light with a material that guides visible light, but the coating absorbs the laser light and generates heat, resulting in a large power laser. cannot transmit light.

OBJECTS OF THE INVENTION In view of the above-mentioned drawbacks, it is an object of the present invention to provide an optical fiber that can also guide visible light coaxially with working light.

Structure of the Invention In the present invention, an optical fiber core that guides working light is placed in a metal tube, heat generation is suppressed by effects such as reflection and heat conduction of the metal, and a visible leading optical path is formed around the outer periphery of the metal tube. .

DESCRIPTION OF EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. 1st
The figure is a longitudinal sectional view of the optical fiber according to the present invention, and FIG. 2 is a view of the optical fiber seen from the end face. Figures 1 and 2
In the figure, 1 is an optical fiber core that guides an infrared power laser beam made of KH2-5 material. 2 is a metal tube in which this is housed, and the optical fiber core 1 is attached at the end.
and is fixed with adhesive 3. 4 is metal tube 2
A visible light guide path made of a resin such as acrylic that can guide visible light is formed by coating on the outer surface of the light guide.

ξ Of course, it may also be formed by inserting cheap transparent 1 fat.

In the optical core constructed as described above, visible light is reflected as shown by arrow a in FIG. 1, or becomes skewed light as shown by arrow A in FIG. 2, and is transmitted through the visible light guide path. FIG. 3 is a block diagram of an optical fiber used for full laser scalpel or laser processing according to the present invention. The CO2 laser beam emitted from the C02 laser oscillator 6 is focused by a condensing lens 6 made of ZnSs, passes through a Ge mirror 7, and enters the optical core 1 made of KH2-6. . The Ge mirror is coated with an anti-reflection coating so that the CO2 laser beam is transmitted therethrough. The CO2 laser beam transmitted by the optical fiber core 1 is again condensed by the second condensing lens 8 (made of Zn5e), and the intended operation, such as cutting or incision, is performed. While the CO2 laser beam is being transmitted through the optical fiber core 1, a small amount of the 002 laser beam leaks out from the outer periphery of the optical fiber core 1 due to phenomena such as scattering.For this reason, conventionally, the core has been directly coated with resin, etc. In such a case, the resin etc. absorbs the leaked light, which causes heat generation and burnout of the fiber, but in this embodiment, the optical fiber core 1 is housed in the metal tube 2, so the leaked light is absorbed. is a reflection of a metal surface.

Heat generation can be suppressed through effects such as heat conduction. The He-Ne laser beam, which is visible light emitted from the laser oscillator 9, is converted into a ring-shaped beam by the conical prism 10, and as the optical path is shown by hatching C, it is converted into a ring-shaped beam by the condenser lens 11. The light is condensed and reflected by the Ge mirror 7 and enters the visible light guide path 4 . The He-Ne laser beam transmitted through the visible light guide path 3 is Zn5
The condensing point of the work light condensed by the condenser lens 8 of s is displayed.

Effects of the Invention As described above, according to the present invention, since the visible light guide path is formed in the optical fiber core via the metal tube,
Visible light can be guided entirely coaxially without reducing the power transmission ability of working light.

[Brief explanation of drawings]

- A longitudinal cross-sectional view, a second view of the same embodiment viewed from the end surface force, and FIG. 1... Optical fiber core, 2... Metal tune, 4... Visible light guide path. Name of agent: Patent attorney Toshio Nakao and 1 other person No. 1
Plan figure 3

Claims (1)

[Claims] An optical fiber comprising an optical fiber core that guides working light, a metal tube in which the optical fiber core is housed, and a visible light guide path formed on the outer surface of the metal tube.