JPH0257245A - Laser endoscope - Google Patents

Abstract

PURPOSE:To perform medical treatment due to laser beams having different wavelengths using one laser oscillator by mounting a non-linear optical element and a mechanism for moving said non-linear optical element to the outside of a laser resonator in the laser resonator of a laser oscillator. CONSTITUTION:The laser beam having a wavelength of 1064nm excited by a YAG laser rod 1 is amplified by a resonator constituted of reflecting mirrors 2, 3 and also converted to 532nm in its wavelength by the non-linear optical element 4 placed in the resonator to pass through the reflecting mirror 2. The laser beam 5 passing through the reflecting mirror 2 to be emitted from a laser oscillator 14 is condensed by a lens 6 to be incident to an optical fiber 7 to be guided to the leading end part thereof and condensed by a lens 8 to irradiate the affected part 15. When the optical element 4 is moved to the outside of the laser oscillator along a guide rail 18, the laser beam having the wavelength of 1064nm amplified by the resonator and transmitted through the reflecting mirror 16 is condensed by the lens 6 and incident to the optical fiber 7 to be guided to the leading end part thereof and condensed by the lens 8 to irradiate the affected part 15.

Description

[Detailed description of the invention] Industrial applications The present invention relates to a medical laser endoscope.

Prior Art Conventional laser endoscopes include, for example, IE Transactions B-M E.B.M.E. 23 (2) (1976), p. 129.
(IEEE Transmission, BME, BME-23(2)
(1978) p129).

FIG. 3 shows a configuration diagram of this conventional laser endoscope, and 13 indicates the endoscope main body. 14 is a laser oscillator, 6 is a lens located at the laser beam emitting portion of the laser oscillator, 7 is an optical fiber made of quartz glass for guiding the laser beam that has passed through the lens, and 8 is the laser beam emitting portion of the optical fiber. This is a lens located at the tip of the endoscope body 13. 12 is a bundle fiber for observing the affected area 15, and 11 is an eyepiece lens. 9
10 is a light source for illumination, and 10 directs the light from the light source 9 to the affected area 1.
This is a bundle fiber for guiding up to 5.

In the conventional laser endoscope configured as described above, the laser beam emitted from the laser oscillator 14 is focused by the lens 6, enters the optical fiber 7, is guided to the tip, and passes through the lens 8. Then, the affected area 15 is irradiated.

Problems to be Solved by the Invention However, with the above configuration, when treatment is performed using laser beams having different wavelengths, separate laser oscillators corresponding to the specific wavelengths are required.

In view of this, an object of the present invention is to provide a laser endoscope that can perform treatment with laser beams of different wavelengths using a single laser oscillator.

Means for Solving the Problems The present invention is a laser endoscope that includes a nonlinear optical element in a laser resonator of a laser oscillator and a mechanism for moving the nonlinear optical element to the outside of the resonator.

Effect of the present invention With the above-described configuration, when the nonlinear optical element is present in the laser resonator, the laser light generated in the laser medium is wavelength-converted by the nonlinear optical element and irradiated to the affected area through the optical fiber.

Furthermore, when the nonlinear optical element is moved from inside the resonator to the outside, laser light generated within the laser medium is irradiated onto the affected area through the optical fiber.

Embodiment FIGS. 1 and 2 are configuration diagrams showing the operating state of a laser endoscope in an embodiment of the present invention. In Figure 1, 1
is a YAG laser rod, 2 has a reflectance of 99.8% or more for laser light with a wavelength of 11064n, and has a wavelength of 532n.
Reflector having a transmittance of 98% for a laser beam of m, 3
is a reflecting mirror that has a reflectance of 99.8% or more for laser beams with wavelengths of 11064n and 532nm, and is configured to form a resonator by opposing the reflecting mirror 2.

4 is B located between the reflecting mirror 2 and the YAG laser rod 1
Nonlinear optical element using a2NaNbsoI6 crystal, 5
is a laser beam with a wavelength of 532 nm emitted from the laser oscillator 14. In Figure 2, 16 is the wavelength 10B4n
Reflector having a transmittance of 1% for a laser beam of m, 17
1 is a laser beam having a wavelength of 11064n emitted from the laser oscillator 14, and 18 is a guide rail for moving the nonlinear optical element 4. The nonlinear optical element 4 performs temperature control at 85° C. so that the second harmonic can be phase-matched.

The laser endoscope of this embodiment shown in FIGS. 1 and 2 basically has the same configuration as the conventional laser endoscope shown in FIG. 3, so the same components have the same parts. Detailed explanations will be omitted by assigning numbers.

The operation of the laser endoscope of this embodiment configured as described above will be described below. In FIG. 1, a laser beam with a wavelength of 11064n excited by a YAG laser rod 1 is amplified by a resonator composed of a reflecting mirror 2 and a reflecting mirror 3, and a nonlinear optical element 4 placed within the resonator. The wavelength is converted to 532 nm and passes through the reflecting mirror 2. Laser light 5 that passes through reflector 2 and is emitted from laser oscillator 14 is focused by lens 6, enters optical fiber 7, is guided to the tip, is focused by lens 8, and is irradiated onto affected area 15. Next, as shown in FIG. 2, when the nonlinear optical element 4 is moved along the guide rail 18 to the outside of the laser resonator composed of the reflecting mirror 16 and the reflecting mirror 3, the A laser beam with a wavelength of 1064 nm passes through a reflecting mirror 16, is focused by a lens 6, enters an optical fiber 7, is guided to the tip, and is then passed through a lens 8.
The light is focused and irradiated onto the affected area 15.

As described above, according to this embodiment, by moving the nonlinear optical element placed in the laser resonator and changing the reflectance of the reflecting mirror that constitutes the resonator, the wavelength 11064n
laser light with a wavelength of 532 nm can be irradiated onto the affected area.

In addition, in this example, Ba2N was used as the nonlinear optical element.
Although an aNbs016 crystal was used, a LINbOa or LIIOa crystal can also be cut out and oriented so that the second harmonic can be phase-matched at room temperature and used as a nonlinear optical element.

DETAILED DESCRIPTION OF THE INVENTION As described in detail, according to the present invention, laser beams of different wavelengths can be irradiated to the affected area using one laser oscillator, so the practical effects thereof are significant.

[Brief explanation of the drawing]

FIG. 1 is a configuration diagram of a laser endoscope according to an embodiment of the present invention, FIG. 2 is a configuration diagram showing different operating states of the embodiment of FIG. 1, and FIG. 3 is a configuration diagram of a conventional laser endoscope. It is a diagram. 1e... YAG laser rod, 2... Reflector, 3...
・Reflector, 4... Nonlinear optical element, 6... Lens,
16... Reflector, 18... Guide rail. Name of agent: Patent attorney Shigetaka Awano and one other person Figure 1 / 6--Second autopsy 9 Figure 2 Figure 2゛7---Final fiber \' 9-11 Teruha 10, /2---Band fiber/S---Patient// \

Claims (1)

[Claims] A nonlinear optical element that converts a laser beam of a first wavelength into a laser beam of a second wavelength is movably installed in a laser resonator that has a laser light source and a first or second reflecting mirror is installed. A first reflecting mirror is installed in the resonator to convert the laser beam of the first wavelength into a laser beam of a second wavelength via the element, and output the laser beam through an optical fiber. . A laser endoscope, characterized in that a second reflecting mirror is installed in the resonator to emit the laser beam of the first wavelength through an optical fiber without going through the element.