JPH02130882A - solid state laser device - Google Patents

Abstract

PURPOSE:To obtain a high laser output which cannot be heretofore obtained by densely disposing exciting semiconductor lasers around the rod of a solid state laser. CONSTITUTION:An assembly of semiconductor lasers 2 is so gathered as to surround a YAG rod 1 disposed at its center, and its light emitting port is directed in a direction of the rod 1. A rear mirror 3 near total reflection and an output mirror 4 partly transmitting are disposed at both ends of the rod 1. When the lasers 2 simultaneously irradiate the rod with excited light, a laser oscillation is generated by the operation of a resonator composed of both the mirrors. Since its output is larger as the input light of the laser is larger, a high output which cannot be heretofore obtained can be attained.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a laser oscillator, and particularly to a solid-state laser device such as a YAG laser that is excited by a semiconductor laser.

[Conventional technology]

Conventionally, regarding solid-state lasers pumped by semiconductor lasers, see Conference on Laser and Electro-Optics 1988 Technical Digest Series, Volume 7, Conference Edition, pages 298 to 299.
Page (Conference on Lasers and
Electro-Optics 1988 Tec
h-nfcal Digest 5eries, Vo
lume7. Conference Edition p
p298-299).

That is, as shown in Fig. 5, the oscillation light (wavelength: 0.81 μm) emitted from the semiconductor laser (not shown) is transmitted through the fiber 1.
1, enters the input lens 12, and enters the YAG rod 13.
The light incident on this YAG rod 13 is YAG
Excite the rod 13. The semiconductor laser beam (0.81 μm) passes through one side of the YAG rod 13, but the diameter is 1.06 μm.
A reflector 11114 having a high reflectance is attached to the light, and an anti-reflection film 15 that allows 1.06 .mu.m to pass is attached at the other end. Further, an external mirror 16 is provided beyond that, so that a part of the 1.06μ irises is passed through and all the others are reflected.

Because it is like this, 1 reflecting mirror 14 and external mirror 1
6 constitutes a resonator, and when the semiconductor laser light enters the YAG rod 13, laser oscillation of 1.06 μm light occurs, and it can be used as a YAG laser.

[Problem to be solved by the invention]

In the above-mentioned conventional technology, since the excitation light is input from the optical axis direction of the YAG rod, the amount of incident light is limited, and no consideration is given to achieving high output.

An object of the present invention is to solve the problems of the prior art.

An object of the present invention is to provide a solid-state laser device that can significantly increase the amount of incident light and realize a high-output solid-state laser such as semiconductor laser-excited YAG.

[Means to solve the problem]

In order to achieve the above object, the present invention allows excitation semiconductor laser light to be incident on the side surface of a solid rod.

[Effect]

For example, in the case of a YAG rod, if the diameter is 6m and the length is 60m, the incident area is 3.14 x (4)
``Gives 28
4 x 6 x 60 x 1130 rrr, and an incident area approximately 40 times larger is obtained. Therefore, much larger input light can be input than before.

〔Example〕

An embodiment of the present invention will be described below with reference to FIG. 1st
Figure (A) is a sectional view of the laser device of the present invention. Further, FIG. 1(B) is a perspective view thereof.

An assembly of semiconductor lasers 2 is gathered to surround a YAG rod 1 placed at the center, and the light emitting ports thereof face the direction of the YAG rod 1.

At both ends of the YAG rod 1, there are disposed a rear mirror 3 that almost completely reflects light of 1.06 μm, and an output mirror 4 that partially (several percent) transmits light. Semiconductor laser 2 simultaneously performs YA
When the G rod 1 is irradiated with excitation light, laser oscillation occurs due to the action of the resonator made up of both mirrors, and the output increases as the input light of the semiconductor laser increases, making it possible to achieve high output that could not be obtained conventionally. Now you can get it.

Further, FIG. 2 shows another embodiment of the present invention. The semiconductor lasers 2 are arranged in many rows in a plane.
The output light is guided by a fiber 5 to the vicinity of the YAG rod 1 and excites the YAG rod 1. In this way, by increasing the density of fibers gathered around the YAG rod 1, a larger input can be given, and therefore a larger YAG laser output can be extracted.

Moreover, by controlling the time or spatial position of the oscillation of the semiconductor laser, it is possible to extract a YAG laser output having arbitrary temporal and spatial changes in waveform. Figure 3 (
a) to (g) show examples thereof.

FIG. 4(b) is a diagram showing an embodiment in which a ground glass surface is used instead of a glossy surface on the cylindrical portion of the YAG rod shown in FIG. 4(a). In the case of the glossy surface 6, the semiconductor laser light that enters the YAG rod 1 repeats absorption and reflection at random, resulting in a certain percentage of loss, and the rest is used as excitation light. If the ground glass surface 7 is used instead, the incident semiconductor laser light will have a gentle distribution 8 and the YAG rod 1 will have a gentle distribution 8.
is incident on the YAG rod 1 and is absorbed homogeneously within the YAG rod 1.

Although there is a loss of about 10% at the time of incidence, the absorption light distribution progresses in a rather -like manner after the incidence, and the uniformity of the excited state within the rod as a whole is significantly increased. Therefore, a stable oscillation mode can be obtained for YAG oscillation light.

It is also suitable for industrial applications.

〔Effect of the invention〕

As explained above, according to the present invention, by densely arranging the excitation semiconductor lasers around the rod of the solid-state laser, it has become possible to obtain a high laser output that could not be obtained conventionally. Furthermore, by making the surface of the rod into ground glass, it has the effect of making the excitation uniform, making it possible to significantly improve the oscillation mode of the solid-state laser.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing one embodiment of the semiconductor laser pumped solid-state laser device of the present invention, FIG. 2 is a block diagram showing another embodiment of the present invention, and FIG. 3 is a diagram showing the time in the configuration of the present invention. , a diagram showing the YAG output with free control of the spatial mode, Figure 4 is Y
FIG. 5 is an explanatory view showing another embodiment of the present invention in which the outer circumferential surface of the AG rod is made of ground glass, and FIG. 5 is a configuration diagram showing a conventional YAG laser oscillator. 1... YAG rod, 2... semiconductor laser, 3...
- Rear mirror, 4... Output mirror, 5... Fiber 7... Ground glass surface. Estimated diagram 1 YAe load 1 2 Semiconductor laser 3, Machine mirror 4 Output mirror 5, Phino 1st (A> / TACrO”y) 39-piece Buddha mirror 2, half 13 pieces - length - 4, output mirror Fig. 4-Fig. 5 Fig. 11, Fiber 72, incidence angle/3 TAcT rod/4.

Claims (1)

[Claims] 1. A solid-state laser device characterized in that a semiconductor laser is arranged in a cylindrical shape and excites a solid rod placed inside the cylinder. 2. A solid-state laser device characterized in that the tip of a fiber into which output light from a semiconductor laser enters from the other end is arranged in a cylindrical shape, and excites a solid rod placed inside the cylinder. 3. The solid-state laser device according to claim 1 or 2, wherein the cylindrical surface of the solid rod is ground glass-like.