JPH0455000B2 - - Google Patents

Description

[Detailed description of the invention]

[Technical Field of the Invention] The present invention relates to a solid-state laser device, and more particularly to a dual-output fixed laser device that can selectively oscillate two or the same types of laser beams. [Technical background of the invention and its problems] Lasers have conventionally been used for nevus treatment. A nevus is a type of mole, and appears colored due to the presence of nevus cells under the skin. This nevus has different colors that are visible through the skin surface depending on the location of the nevus cells.
This will be explained with reference to FIGS. 1a, b, and c. In FIGS. 1a, b, and c, 21 is the epidermis, 22 is the dermis, 23 is the hair follicle, and 24 is the nevus cell. In FIG. 1a, nevus cells 24 are present in the lower part of the epidermis 21, and are visible as brown penetrating cells on the skin surface. In Figure 1b, nevus cells 2 are located in the upper part of the dermis 22.
4 exists, and it is visible through the black color. 1st
In Figure c, nevus cells 24 are present deep in the dermis 22 and are visible in blue. Among these, to cure the nevus cell 24 shown in Figure 1a, ruby laser (wavelength 0.7μ) is applied at 40J for 1 time.
It is irradiated for about ms. Irradiation with this ruby laser can heal nevus cells without damaging the skin. On the other hand, even if a ruby laser is used for the nevus cells 24 shown in FIGS. 1b and 1c, the nevus cells 24 cannot be cured. This is due to the unique dissipation length of the laser beam (the depth at which 90% of the output is absorbed) for the living body. The dissipation lengths of various laser beams for irradiated substances are shown in the table below.

[Purpose of the invention]

This invention was made in view of the above circumstances, and is a dual-output solid-state that can selectively oscillate two types of laser beams, and that can reduce the size of the device and the manufacturing cost. The object of the present invention is to provide a laser device. [Summary of the Invention] The outline of the invention for achieving the above-mentioned object is to provide a single excitation light generation light source and a laser beam generating laser beams each having a different wavelength by inputting the light from the excitation light generation light source. first and second laser resonant systems; a reflecting mirror that reflects and guides the excitation light from the excitation light generating light source to the first and second laser resonant systems, and the first and second laser resonators; The double-output solid-state laser device is characterized by having shutter means arranged on the optical axis of the system and selectively shielding one of these laser resonant systems. [Embodiment of the Invention] An embodiment of the present invention will be described below with reference to the drawings. FIG. 2 is a schematic perspective view of a dual-output solid-state laser device, and FIG. 3 is a sectional view of a metal reflecting mirror. Second
In the figure, the dual-output solid-state laser device has a housing 1
, a metal reflecting mirror 2 provided within the housing 1, a rod-shaped excitation light generating light source 3 disposed within the metal reflecting mirror 2, and a 2 disposed parallel to the excitation light generating light source 3.
two laser resonant systems 4, 5, and two laser resonant systems 4, 5
The optical shutters 6 and 7 are movable intersecting the optical axis of the optical shutter. As shown in FIG. 3, the metal reflecting mirror 2 has a cross-sectional shape that is the ring interval when two ellipses A and B are superimposed on the same plane, with one of the ellipses A and B having a common focal point. It has a cylindrical shape, and its inner surface is a metal reflective plate. The excitation light generation light source 3 emits, for example, high-output light in a pulsed manner.
The Xe lamps are arranged along a common focal point within the metal reflector 2. Although not shown, the light source 3 for generating excitation light is connected to a power source equipped with a large-capacity capacitor for instantaneously supplying large power and an LC delay circuit that determines the supply time of this power. are doing. The two laser resonant systems 4 and 5 are arranged parallel to the excitation light generating light source 3 along the other focal point of the metal reflecting mirror 2. The laser resonant system 4 consists of a bar-shaped solid rod 8 disposed within the metal reflecting mirror 2, and reflecting mirrors 9a and 9b disposed opposite to each other along the long axis of the solid rod 8. The reflectance of the reflecting mirror 9a is lower than that of the reflecting mirror 9b. On the other hand, the laser resonant system 5 also has the same configuration as the laser resonant system,
A solid rod 1 placed inside a metal reflector 2
0, and reflecting mirrors 11a and 11b arranged oppositely on the long axis extension of the solid rod 10. The reflectance of the reflecting mirror 11a is lower than that of the reflecting mirror 11b. The metal reflecting mirror 2, the light source 3 for generating excitation light, and the two laser resonant systems 4 and 5 constitute the first invention. the optical shutter 6,
7 is rotatably held at one end by shafts 6a and 7a protruding from the housing 1, and the other end is formed of a material through which light does not pass. And light shutter 6
is adapted to move in and out between the solid rod 8 and the reflecting mirror 9a on the optical axis of the laser resonant system 4. The optical shutter 7 also includes a solid rod 10 and a reflecting mirror 1 on the optical axis of the laser resonant system 5.
1a so that it can move in and out. An optical fiber 14 is disposed on the optical axis extension of the laser resonant system 4 and outside the reflecting mirror 9a via condensing lenses 12 and 13.
It is designed to guide the laser light emitted from the laser beam. Similarly, on the extension of the optical axis of the laser resonant system 5 and outside the reflecting mirror 11a, there is a condenser lens 1.
An optical fiber 17 is disposed through the laser resonator system 5 and 16 to guide the laser light emitted by the laser resonant system 5. The operation of the dual-output solid-state laser device configured as above will be explained. First, to operate this dual-output solid-state laser device, the light source 3 for generating excitation light is turned on in a pulsed manner. Then, as shown in FIG. 3, the light from the excitation light generating light source 3 enters the solid rods 8, 10 either directly or after being reflected by the metal reflecting mirror 2.
At this time, the excitation light generating light source 3 and the solid rod 8 are located at the focal point of the ellipse A shown in FIG.
The light source 3 for generating excitation light and the solid rod 10 are located at the focal point of the ellipse B. Therefore, when the light emitted from the excitation light generating light source 3 is reflected on the portion of the metal reflecting mirror 2 belonging to the ellipse A, it is reflected by the solid rod 8.
When the light is focused on the solid rod 10 and reflected on the portion belonging to the ellipse B, the light is focused on the solid rod 10. Therefore, the light emitted from the excitation light generation light source 3 can be used as excitation light without wasting it. The solid rods 8 and 10 into which the excitation light is incident generate laser light, and the laser light is resonated in the laser resonant systems 4 and 5. In this way, according to the first invention, by using one light source, two
Laser light can be emitted more efficiently than a solid rod. Furthermore, if one of the laser resonant systems 4, 5 is shut off by the optical shutters 6, 7, laser light can be generated only from the other laser resonant system. For example, if one of the solid rods 8 and 10 is used for a ruby laser and the other is used for a YAG laser, the ruby laser and the YAG laser can be selected and used in one device by switching the optical shutters 6 and 7. can do.
The laser beam generated from one of the laser resonant systems 4 and 5 is extracted from the reflecting mirror 9a or the reflecting mirror 11a, which has a low reflectance, and can be emitted from either one of the optical fibers 14 and 17. Therefore, it is convenient when two types of laser beams are used depending on the position of the nevus cell, such as in nevus treatment. It goes without saying that the present invention is not limited to the embodiments described above, and includes various modifications within the scope of the gist of the present invention. For example, a metal reflecting mirror 2 whose cross-sectional shape is a ring interval made by superimposing two ellipses A and B is not limited to one in which each focal point is on a straight line as shown in FIG. It may also have a cross-sectional shape in which two ellipses A and B are superimposed so that their long axes intersect with each other having one focal point in common. Even in this case, the light emitted from the excitation light generating light source 3 can be condensed onto the solid rods 8 and 9 without waste. Further, the optical switches 6 and 7 disposed midway along the optical axes of the laser resonant systems 4 and 5 are not limited to mechanically operated ones as in the above embodiment, but are also made of materials whose transmittance changes depending on the electric field, such as liquid crystals. , PLZT, KDP (polarizer), etc. In the present invention, two types of laser beams are selectively extracted from the laser resonant systems 4 and 5, and the guide of the laser beams emitted from the laser resonant systems 4 and 5 does not matter. Therefore, the laser light emitted from the dual-output solid-state laser device can be used as it is without using the optical fibers 14 and 17, or it can be guided by combining a reflecting mirror. As shown in FIG. 5, the laser beam from the laser resonant system 4 is directed through a reflecting mirror 18 and a half mirror 19 to an optical fiber 20 provided in the optical path of the laser beam from the laser resonant system 5. I can also guide you. [Effects of the Invention] As explained above, according to the first invention, it is possible to provide a dual-output solid-state laser device that can efficiently generate two types of laser light in one device, and further, According to the second invention,
A dual-output solid-state laser device that can selectively extract two types of laser beams can be provided.
Therefore, compared to the conventional method using two devices, the device can be made smaller and the manufacturing cost can be significantly reduced. In particular, the effect of contributing to nevus treatment using two types of laser beams is extremely large.

[Brief explanation of the drawing]

Figures 1 a, b, and c are schematic explanatory diagrams explaining the location of nevus cell generation, Figure 2 is a schematic perspective view of a dual-output solid-state laser device that is an embodiment of the present invention, and Figure 3 is a metal reflection diagram. FIG. 4 is a cross-sectional view showing a modified example of the metal reflecting mirror, and FIG. 5 is a schematic perspective view in which the output light guide path of a dual-output solid-state laser device is one optical fiber. 2...Metal reflecting mirror, 3...Light source for generating excitation light,
4, 5... Laser resonance system, 6, 7... Optical shutter, 8, 10... Solid rod, 9a, 9b, 11
a, 11b...Reflector.

Claims (1)

[Claims] 1. a single excitation light generation light source; first and second laser resonant systems that receive light from the excitation light generation light source and generate laser beams of different wavelengths;
a reflecting mirror that reflects and guides the excitation light from the excitation light generation light source to the first and second laser resonant systems, and a reflecting mirror disposed on the optical axis of the first and second laser resonant systems; 1. A dual-output solid-state laser device comprising shutter means for selectively shielding one side of a laser resonance system.