JPS6360578A - Solid-state laser element - Google Patents

Abstract

PURPOSE:To generate laser beams having different wavelengths while miniaturizing a solid laser element by forming an optical waveguide, to which an element for laser oscillation is doped, onto a substrate and mounting mirrors, through which beams from a semiconductor laser element fitted near one end surface of the optical waveguide is transmitted and which reflect beams from the element, onto both end surfaces. CONSTITUTION:When a semiconductor laser element 13 is oscillated, laser beams from a striped oscillation region 14 are outputted in the direction of an optical waveguide 12, and transmitted through a reflecting mirror on an optical incident end surface 15a and the greater part is projected to the optical waveguide 12. Since an element for laser oscillation is doped to the optical waveguide 12 at that time, beams are generated by laser transition, and reflected by mirrors fitted to both end surfaces 15a, 15b of the optical waveguide 12, and beams repeat resonance in the optical waveguide 12. Accordingly, laser beams having a wave range different from laser beams by the semiconductor laser element 13 can be outputted from the optical outgoing end surface 15b of the optical waveguide 12.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a solid-state laser device used in fields such as optical communication and optical information processing.

(Prior Art) In fields such as optical communication and optical information processing, solid-state laser elements, semiconductor laser elements, fiber laser elements, and the like are used as key devices. In such fields, the requirements for laser ropes include being small and lightweight, being resistant to environmental changes, being inexpensive and easy to handle, and so on.

However, conventional solid-state laser devices are large, difficult to handle, and generally expensive. On the other hand, semiconductor laser elements are small, lightweight, and easy to handle, and therefore, in recent years, applications have been actively attempted in fields such as optical communications. In particular, research in long wavelength bands is progressing in connection with the fact that the loss of optical fibers becomes smaller in long wavelength bands. However, regarding semiconductor laser devices, for example, it is difficult to obtain an emission wavelength of 1 μm or more with a Qa AS-based device, and it is possible to obtain an emission wavelength of 1.0 to 1.5 μm with, for example, an InP-based device. However, the problem often occurred that it was difficult to manufacture the laser device.

Conventionally, in order to solve the above-mentioned problems, a fiber laser element as shown in FIG. 4, for example, was used to emit laser light with an emission wavelength of about 1 μm or more. As shown in the figure, a laser beam from a semiconductor laser device 1 having an oscillation wavelength in the 0.8 μm band, for example, is coupled to a single mode fiber 2. At this time, the fiber 2 is doped with, for example, about 0.03% Nd3+ (neodymium), and high reflection mirrors 3a and 3b are formed on both end faces.According to such a fiber laser element, 1
．． It is possible to emit 1 q of laser light with a wavelength of about 0.8 μm.

[Problem that the invention seeks to solve]

However, in such a fiber laser device, the length of the single mode fiber 2 is about 2 m, and therefore, the laser device is significantly larger than a semiconductor laser device and has the problem of being difficult to handle.

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to provide a solid-state laser device that is small, lightweight, easy to handle, and can easily emit 1 q of laser light with an emission wavelength different from that of a semiconductor laser device (e.g., an emission wavelength of about 1 μm or more). do.

[Means for solving problems]

A solid-state laser device according to the present invention is a semiconductor laser device in which an optical waveguide doped with an element for laser oscillation is formed on a substrate, and laser light from a light-emitting end face is incident on a light incident end face of the optical waveguide. The present invention is characterized in that a reflecting mirror is further formed on the light input end face and the light output end face of the optical waveguide to transmit the laser light from the semiconductor laser element and reflect the laser light due to the doped element.

[Effect]

Since the solid-state laser device of the present invention is configured as described above, the element doped in the optical waveguide acts to generate light of different wavelengths depending on the laser light from the semiconductor laser device, and the reflection on both end faces of the optical waveguide is caused. The mirror allows the laser light from the semiconductor laser device to enter and resonates the light from the doped element within the optical waveguide. Therefore, the mirror allows the laser light in a wavelength band different from that of the laser light from the semiconductor laser device to enter the optical waveguide. It moves to output from the output end face.

〔Example〕

Hereinafter, some embodiments of the present invention will be described with reference to the accompanying drawings. In the following description, the same elements are given the same reference numerals and redundant description will be omitted.

FIG. 1 is a perspective view of a solid-state laser device according to a first embodiment. A striped single mode optical waveguide 12 doped with, for example, Nd3+ as an element for laser excavation is formed on a substrate 11 made of quartz glass, and a groove is formed on the substrate 11 at one end of the optical waveguide 12. has been done. A semiconductor laser element 13 having an oscillation wavelength in the 0.8 μm band, for example, is disposed in this groove, and a striped oscillation rA region 14 in this element 13 is located on the same optical axis as the optical waveguide 12 of the substrate 11. Further, a reflecting mirror made of, for example, a dielectric multilayer film is formed on the end face (light incident end face) 15a of the optical waveguide 12 on the side of the semiconductor laser element 13 and the end face (light emitting end face) 15b on the opposite side. The reflecting mirrors on the end surfaces 15a and 15b are the semiconductor laser element 13.
80% of light of wavelength -o, s μm from the LX is transmitted,
N d3 + wavelength from doped optical waveguide 12 -1,1μ
Reflect more than 99% of the light of m.

Next, an example of a method for manufacturing the solid-state laser device shown in FIG. 1 will be described with reference to FIG. 2. FIG. 2 is a perspective view of the element according to the manufacturing process.

First, 130.29 Si (OC2H
5) In a mixture of 4 and 124.89 ethanol,
Add 459 water containing 20M of 13% ammonia water and stir. Note that these raw materials are mixed while being heated to 60'C.

Next, this is placed in a sealed bottle and left in a constant temperature bath at 60°C for 9 days to obtain a sol solution through decomposition. Therefore, 1.29 Si (OCH3)4 is added to this sol solution 209.
Add and mix well. Then, add 59 water containing 2 drops of 13% ammonia water and 3.87 ethanol to this, and stir well. Thereafter, the sol solution is vacuumed at very high temperature until it boils, and the solution is kept in the boiling state for 5 minutes and then taken out.

Next, place it in a Teflon petri dish, cover it lightly with aluminum foil, and leave it in a constant temperature bath at 60'C.

In this way, the sol solution will turn into a gel the next day, and a dry gel will be obtained in about one week.

Next, this dried gel was removed from the petri dish and polished.
As shown in FIG. 2(a), the plate-shaped gel 21 has a size of, for example, 30#x15#x5M.

Next, this plate-shaped gel is coated with, for example, 7
A mask is applied, leaving a stripe with a width of about μm, and an ethanol solution containing about 3% boric acid is soaked into the mask. Then, a mixture of 1.07% of S. (OCH3)4, 3.399% of a solution of Nd methoxide dissolved in ethanol (Nd: 1.08%), and 2.209% of Qe(OC2H5)4 was added. Add 15 sheets of masked gel to the solution.
Immerse for about 2 seconds. Then, it was immersed in a solution containing water and ethanol mixed at a weight ratio of 1:1 and 3% boric acid added.
Leave it overnight. After that, take out this plate-shaped gel and
Dry overnight.

Next, this plate-shaped gel was heated at 500'C for 24 hours at 800°C.
The gel is calcined in the air for about 8 hours to burn off the organic components and photoresist in the gel plate. Furthermore, by heating the substrate to about 1300'C at a heating rate of 200'C/hour in a He gas atmosphere, a planar waveguide 22 can be formed on the substrate as shown in FIG. 2(b).

Then, the vicinity of one end of this waveguide 22 is approximately 30 μm thick.
By etching to a depth of , grooves 23 as shown in FIG. 2(C) can be formed. Then, one end surface 2 of the waveguide 22
Step 4: Finish to a mirror surface.

Next, reflective mirrors 25 made of a dielectric multilayer film are formed on both end faces of the waveguide 22.
It is designed to transmit 80% of the light of 1.1 μm and reflect 99% or more of the light of 1.1 μm. Then, a semiconductor laser element with an emission wavelength of 0.82 μm is placed in the groove 23, and the laser output is adjusted so that it enters the waveguide. Furthermore, by fixing the position of the semiconductor laser element and attaching a radiator (not shown), the solid-state laser element shown in FIG. 1 is completed 1q.

The manufacturing process of the solid-state laser device according to the present invention is not limited to the above. For example, Vycor porous glass may be used instead of the plate-shaped gel, and the immersion time in the additive solution may be 1 hour instead of 15 seconds.

Next, the operation of the solid-state laser device according to the first embodiment will be explained. First, when the semiconductor laser device 13 shown in FIG. 1 is oscillated with a power of about 1.5 m''vV, laser light from the oscillation region 14 shaped like a strip 1 is outputted in the direction of the optical waveguide 12. At this time, the oscillation wavelength of the laser beam is, for example, 0.8 μm, and the light incidence end face 15 of the optical waveguide 12
Since the reflecting mirror a is designed to transmit 80% or more of light with a wavelength of approximately 0.8 μm, most of the laser light is incident on the optical waveguide 12.

At this time, the optical waveguide 12 is doped with Nd3+ as an element for laser oscillation, and therefore light with a wavelength of, for example, 1.05 μm is generated by laser transition. Then, 1.1 is applied to both end surfaces 15a and 15b of the optical waveguide 12.
Since a mirror is provided that reflects 99% or more of light with a wavelength of approximately μm, the light caused by Nd3+ repeatedly resonates within the optical waveguide 12. That is, the optical waveguide 12 functions as a resonator of the solid-state laser element.

Therefore, the wavelength from the light output end face of the optical waveguide 12 is 1.0
A laser beam of 5 μm can be obtained.

Therefore, an optical fiber (not shown) is attached to the light emitting end surface 15b.
If these are combined, it can be used in systems such as optical communication.

FIG. 3 is a perspective view of a solid-state laser device according to a second embodiment of the invention. The difference between this and the one in FIG. 1 is that a guide groove 17 for arranging an optical fiber (not shown) is formed on the substrate 11 on the light output end face 15b side of the optical waveguide 12.
This is achieved by providing Such a guide groove 17 is
It can be formed at the same time as the groove for providing the semiconductor laser element 13 is formed by etching. This second embodiment has the advantage that the optical fiber can be positioned, aligned, and fixed quickly and easily.

The present invention is not limited to the first and second embodiments described above, and various modifications are possible. For example, the substrate is not limited to a quartz-based glass substrate, and the shape of the groove formed in the substrate is not limited to that of the embodiment.

The semiconductor laser device is not limited to Ga AI As in the 0.8 μm band, but may be in other wavelength bands. In addition to Nd, Er (
(Erbium), HO (Holmium), etc. can be used, and in particular, when Er is used, it is possible to excavate in the 1.5 μm band and minimize the optical loss of the optical fiber. In general, the optical fiber may be connected to the light output end face of the optical waveguide by using a refractive index matching liquid or by fusion splicing.

[Effects of the Invention] As described above in detail, according to the present invention, an optical waveguide doped with an element for laser excavation is formed on a substrate, a semiconductor laser element is provided near one end face of the optical waveguide, and a semiconductor laser element is provided near one end face of the optical waveguide. By forming mirrors on both end faces of the optical waveguide that transmit the light from the semiconductor laser element and reflect the light from the doped element, the laser light from the semiconductor laser element causes laser light of different wavelengths to be transmitted within the optical waveguide. There are effects that can be generated. The present invention particularly provides 0.7 to 0.9 μm
It is suitable for obtaining a solid-state laser device with an emission wavelength of about 1 μm or more by using a semiconductor laser device with an emission wavelength in the band.

[Brief explanation of drawings]

FIG. 1 is a perspective view showing the structure of the first embodiment of the present invention, FIG. 2 is a perspective view showing an example of the manufacturing process of the solid-state laser device shown in FIG. 1, and FIG. 3 is a perspective view showing the structure of the first embodiment of the present invention. FIG. 4 is a perspective view showing the configuration of the second embodiment, and FIG. 4 is a configuration diagram of the conventional example. 11... Quartz-based glass substrate, 12... Optical waveguide, 1
3... Semiconductor laser element, 15a... Light incidence end surface,
15b...Light emission end surface, 17... Guide groove. Patent Applicant: Sumitomo Electric Industries, Ltd. Representative Patent Attorney Yoshiki Hase Figure 1 IA view of the manufacturing process of the first embodiment Figure 2 Perspective view of the solid-state laser cord of the second embodiment Figure 3 Conventional example Configuration diagram Figure 4

Claims (1)

[Claims] 1. A substrate; an optical waveguide formed on the substrate and doped with an element for laser oscillation; a semiconductor laser element configured to allow light to be incident on an incident end face; and a laser beam formed on a light incident end face and a light output end face of the optical waveguide to transmit laser light from the semiconductor laser element and to generate laser light from the doped element. A solid-state laser element comprising: a reflecting mirror that reflects; and a solid-state laser element. 2. The solid-state laser device according to claim 1, wherein a groove for arranging the semiconductor laser is formed in the substrate on the light incident end face side of the optical waveguide.