JP2001217490A - Method of manufacturing for laser device and optical amplifier - Google Patents

Abstract

PROBLEM TO BE SOLVED: To inexpensively provide a laser device and an optical amplifier, whose use efficiency of exciting light is high and which have high output or high efficiency. SOLUTION: Excitation structure for distributing and introducing exciting light 51 to a laser guiding body from an existing light guiding body 2 by a process for forming the exciting light guiding body 2 in a prescribed shape by winding a light suiting member 21 having a sheet shape and flexibility while a supporting body 6 gives and holds the shape and a process for winding or folding the prescribed length range of the long laser beam guiding body 1 along the surface of the supporting body 6 or the exciting light guiding body 2.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention provides a laser light output by laser oscillation or amplification by causing a laser active substance contained in a long laser light guide such as a laser fiber to absorb excitation light. More particularly, the present invention relates to a laser device and a method for manufacturing an optical amplifier which are effective when applied to fields such as optical communication, optical measurement, and laser processing.

[0002]

2. Description of the Related Art For example, in the fields of optical communication, optical measurement, and laser processing, it is desired to develop a laser device with higher output or higher efficiency and lower cost. Conventionally, an optical fiber laser device has been known as a device which has a high possibility of satisfying this requirement. An optical fiber laser device uses an optical fiber (or laser fiber) comprising a core containing a laser active substance and a clad surrounding the core coaxially as a laser light guide (so-called laser medium). By appropriately selecting the diameter of the core portion, the difference in the optical refractive index between the core portion and the clad portion, etc., the transverse mode of laser oscillation can be made relatively simple. Further, by confining the light within the optical fiber at a high density, the interaction between the laser active substance and the light can be enhanced. Further, since the interaction length can be increased by increasing the length of the optical fiber, spatially high-quality laser light can be generated with high efficiency. Therefore, high-quality laser light can be obtained relatively inexpensively.

Here, in order to further increase the output or the efficiency of the laser beam, an area (usually a laser active substance) to which laser active ions or dyes or other luminescent centers (hereinafter referred to as laser active substances) of an optical fiber are added. It is necessary to efficiently introduce and absorb the excitation light into the core part). However, usually, when the core diameter is set so as to satisfy the single-mode waveguide condition, the diameter is limited to ten and several μm or less, so that it is generally difficult to efficiently introduce pump light to this diameter. It is. As means for overcoming the difficulties described above, for example,
Japanese Patent Application No. 1-284255 (Japanese Patent Application No. 10-350306) proposes a "fiber laser device and fiber processing device". In the laser device of the proposed technique, a laser fiber having a core containing a laser active material and outputting a laser beam from an end portion when the active material is excited is used for exciting the active material. It is in direct contact with the light guide structure capable of confining light or indirectly via an optical medium, and the active substance is excited by excitation light incident through the contacted portion.
In other words, an excitation light guide having a structure capable of confining the excitation light is used, and the excitation light is introduced from the side surface of the fiber laser light guide through the excitation light guide. It is introduced in a state of being distributed in the longitudinal direction of the laser light guide. The laser light contained in the laser light guide can be excited by the excitation light distributed and introduced into the laser light guide in this manner.

[0004] The introduction of the excitation light into the excitation light guide can be carried out through an incident prism or the like provided at an arbitrary position of the excitation light guide. The pumping light that has entered the pumping light guide repeats reflection inside the pumping light guide, spreads throughout the pumping light guide, and makes direct or indirect contact with the side surface of the laser light guide. From the part to be introduced into the laser light guide. The excitation light guide is, for example, a hollow cylindrical or flat disk-shaped structure, and propagates the excitation light introduced from the excitation light source while confining it by internal reflection. When the laser light guide is brought into optical contact with the surface of the excitation light guide over a predetermined length by winding a fiber laser light guide around this structure, the laser light guide is confined inside the excitation light guide. The excited excitation light enters the laser light guide through the contact portion. In a laser device having such an excitation structure, it is easy to introduce the excitation light into the fiber laser light guide. The structure forming the light body can be introduced from an arbitrary position, thereby facilitating excitation by a plurality of excitation sources.

[0005]

By the way, in the above-mentioned conventional laser device, in order to efficiently introduce the excitation light from the excitation light guide to the laser light guide, the excitation light guide and the laser light guide are combined. It is necessary to guide the excitation light as efficiently as possible to the region where the contact is made. In addition, in order to efficiently excite the laser active substance contained in the laser light guide, the length of the area where the excitation light guide and the laser light guide are in contact with each other, that is, the distribution introduction range of the excitation light is largely secured. There is a need to. For this reason, the excitation light guide needs to have a structure with a surface area as large as possible.On the other hand, in order to increase the ratio of absorption of the excitation light into the core portion, the internal light volume may be as small as possible. Required. This is because if the internal volume of the excitation light guide is large, the effective absorption coefficient decreases, and the excitation efficiency decreases due to loss such as scattering.

Therefore, the above-mentioned excitation light guide has a large surface area, for example, is formed in a hollow cylindrical shape or a flat disk shape.
It was necessary to make the structure as thin as possible. However, forming such a structure by molding or processing an optical material such as glass has a problem in terms of productivity and cost. For example, Japanese Patent Application Laid-Open No. 11-2
In the “fiber laser device and fiber processing device” disclosed in Japanese Patent Application No. 84255 (Japanese Patent Application No. 10-350306), a glass circular tube is exemplified as the excitation light guide, but in order not to lower the excitation efficiency. It is necessary to reduce the wall thickness of the circular pipe to at least about 0.5 mm, and it is difficult to form such a thin-walled structure by machining or the like. Did not.

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and has an advantage in that excitation light is distributed and introduced into a laser light guide having a long structure such as a laser fiber, for example, it has excellent light condensing properties. It is an object of the present invention to provide a method for manufacturing a high-output or high-efficiency laser device and an optical amplifier by increasing the utilization efficiency of pump light while maintaining the advantages of a fiber laser such that the output and the transverse mode are thermally stable. Aim.

[0008]

A first means of the present invention is as follows.
A pump light guide that propagates the pump light while confining the pump light; and a length that includes a laser active material and that the pump light is distributed and introduced from the pump light guide to excite the laser active material and output laser light. A method of manufacturing a laser device comprising a flexible and flexible laser light guide, wherein a thin, flexible light guide member is wound while a shape and shape are maintained by a support. Forming an excitation light guide having a predetermined shape by the method, wherein a predetermined length range of the laser light guide is optically indirectly applied to the excitation light guide directly or indirectly through an optical medium transmitting the excitation light. Winding or turning the laser light guide before or after the excitation light guide is formed so as to form an intimate contact state, whereby the laser light guide is separated from the excitation light guide. It is a manufacturing method of the laser device, and forming a pumping structure to distribute guide the excitation light.

The second means is that, in the first means, the laser light guide is wound or folded along the surface of the excitation light guide formed on the support, thereby forming the laser light guide. A method for manufacturing a laser device, wherein a predetermined length range optically contacts the excitation light guide to form an excitation structure in which excitation light is distributed and introduced.

[0010] A third means is that, in the first or second means, the excitation light guide is wound on a support on which the laser light guide is wound in advance, so that the laser light guide has a predetermined shape. A method for manufacturing a laser device, wherein a length range optically contacts the excitation light guide to form an excitation structure in which excitation light is distributed and introduced.

[0011] The fourth means is any one of the first to third means, wherein the shaping of the light guide member in the step of forming the excitation light guide and / or the winding or folding of the laser light guide is performed. This is a method for manufacturing a laser device that is performed while heating.

A fifth means is a method for manufacturing a laser device, wherein in any one of the first to fourth means, the excitation light guide formed into a predetermined shape by winding is annealed.

[0013] A sixth means is that in any one of the first to fifth means, the excitation light guide is formed using a ribbon-shaped light guide member having two main surfaces, a front surface and a back surface. A method for manufacturing a laser device, wherein a laser light guide is brought into optical contact with either one of the two main surfaces directly or via an optical medium transmitting excitation light.

A seventh means is the fiber according to any one of the first to sixth means, comprising: a core portion containing a laser active substance; and a cladding portion surrounding the core portion and providing a predetermined waveguide structure. This is a method for manufacturing a laser device using a laser light guide in a shape of a circle.

Eighth means is to form an excitation light guide by winding a light guide member in a groove previously formed in the support, and to form the excitation light guide and the excitation light from the excitation light guide. The laser light guide of the portion receiving the distribution introduction is housed in the groove, and the structure is formed such that the excitation light leaking from the excitation light guide is confined in the groove and distributed and introduced into the laser light guide. A method for manufacturing a laser device.

The ninth means is an excitation light guide for confining and propagating the excitation light, and a laser active material containing a laser active material, and the excitation light being distributed and introduced from the excitation light guide to excite the laser active material. A method for manufacturing an optical amplifier having a long and flexible laser light guide for performing optical amplification by performing a light guide member having a thin and flexible shape with a support. A step of forming an excitation light guide having a predetermined shape by winding while maintaining the shape; and an optical medium in which a predetermined length range of the laser light guide is directly or through the excitation light with respect to the excitation light guide. Winding or folding the laser light guide before or after the excitation light guide is formed, so as to form an optical contact state indirectly through,
A method of manufacturing an optical amplifier, comprising forming an excitation structure for distributing and guiding excitation light from the excitation light guide to the laser light guide.

According to the above-described means, the pumping light guide having a light guiding structure capable of distributing and introducing the pumping light to the laser light guide while efficiently confining the pumping light with a small transmission loss of the pumping light is relatively simple. It can be formed at low cost. As a result, the advantage of the method of distributing and introducing excitation light into a laser light guide having a long structure such as a laser fiber,
For example, while maintaining the advantages of fiber lasers, such as excellent condensing properties and stable thermal output and transverse mode, the utilization efficiency of pump light is increased, and high-output or high-efficiency laser output or optical amplification is achieved at low cost. Is achieved. In the case where the shaping of the light guide member or the winding or folding of the laser light guide in the step of forming the excitation light guide is performed while heating the shaping or the wound or folded portion, a heating unit or It is desirable that the process be performed so that the vicinity does not come into contact with another member such as a support. This is because when the light guide member or the laser light guide is heated, if the heating portion or its vicinity is in contact with or in proximity to a low-temperature object such as a reel (support), heat is taken away by the support. In addition, the heating cannot be performed sufficiently, and a temperature distribution occurs in the heated portion, so that the stress may not be sufficiently released on the low-temperature side (support side). for that reason,
The uneven residual stress may cause a decrease in strength. Further, if the material is heated so that the temperature on the low temperature side is higher than the softening point, melting and evaporation may occur on the high temperature side, the surface may be deteriorated, and the light propagation efficiency may be reduced. Therefore, when shaping the light guide member or winding or turning the laser light guide, means for guiding the front or rear or front and back of the heating portion of the light guide member or the laser light guide by, for example, a guide member. Therefore, it is desirable that the heating section or the vicinity thereof be performed so as not to contact another member such as a support.

[0018]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will be described below with reference to the drawings. In addition, between each figure,
The same reference numerals indicate the same or corresponding parts. FIG. 1 schematically shows an embodiment of a main part of a method for manufacturing a laser device according to the present invention. In the method shown in the figure, first, a thin and flexible light guide member 21 and a support 6 having a predetermined matrix shape are used. The light guide member 21 is a long and flexible optical material, and here, a quartz glass formed in a ribbon shape is used. The support 6 is formed in a cylindrical shape using a good heat conductive material such as aluminum. The support 6 is driven to rotate around the axis of the cylinder and is fed and moved in the axial direction.
The light guide member 21 is spirally densely wound around the support 6 while being pressed against the outer surface of the cylindrical support 6 that is fed and moved in the axial direction while being driven to rotate about the axis. The winding process of the light guide member 21 can be performed under a cold condition, but is preferably performed while locally heating the portion of the support 6 where the light is wound. It is efficient that the heating is performed by locally irradiating the laser light beam 81 to the light guide member 21 at a portion pressed and wound on the support 6. Due to the local heating by the irradiation of the laser light beam 81, the light guide member 21 is stably and smoothly pressed against the surface of the support 6 without causing breakage or cracking, and without causing shape instability due to springback. To form the excitation light guide 2 having a predetermined shape. The laser light beam 81 can be generated using a CO2 laser device 82.
Laser light beam 8 emitted from CO2 laser device 82
1 is, after the beam diameter is expanded by the beam expander 83, the direction is changed by the mirror 84, and the beam is formed into a linear pattern beam having a length corresponding to the width of the light guide member 21 by the cylindrical lens 85. It is collected. The laser light beam 81 having this linear pattern is projected through a mask plate 86 having a slit-shaped projection window so as to linearly irradiate the entire width of the light guide member 21 with no excess or shortage.

FIG. 2 schematically shows one embodiment of the light guide member used in the method shown in FIG. In the figure,
(A) shows the appearance of the light guide member 21, and (c) schematically shows a cross section thereof. The light guide member 21 is a long and flexible optical material, and the light guide member 21 used in the method shown in FIG. A ribbon-shaped material is particularly suitable. The ribbon-shaped light guide member 21 can be manufactured by, for example, stretching or drawing quartz glass.

FIG. 3 schematically shows an embodiment of the excitation light guide formed by the method shown in FIG. The excitation light guide 2 shown in FIG. 1 has a ribbon-shaped light guide member 21 spirally and densely wound around the outer surface of a cylindrical support 6.
As a whole, one circular tube structure is formed. The tubular excitation light guide 2 has a very thin structure because the thickness of the ribbon-shaped light guide member 21 forming the same is the thickness of the tube wall. The excitation light guide 2 formed as described above can be used as it is, but is preferably used after performing an annealing treatment as a post-treatment. The annealing process can reliably remove microcracks and stress strains inside the excitation light guide 2, and can obtain optical stability and homogeneity as a light guide material. The effect of improving the characteristics of confinement and propagation is obtained.

FIG. 4 schematically shows a first embodiment of the laser device constructed by the method shown in FIG. 1A shows an outline of a laser device, and FIG. 1B shows a partial cross section of a laser light guide 1 used in the laser device.
The laser device shown in FIG. 1A is manufactured through the step of winding the laser light guide 1 along the surface of the excitation light guide 2 described above. This laser device has a laser light guide 1
Has a pumping structure in which the pumping light 51 is distributed and introduced from the pumping light guide 2 to the laser light guide 1 when the predetermined length range optically contacts the pumping light guide 2. The laser light guide 1 is configured using a flexible optical fiber that forms a long and continuous waveguide structure. The optical fiber-shaped laser light guide 1 is also called a laser fiber, and as shown in FIG. 1B, a core 11 containing a laser active substance and a clad 1 surrounding the core 11.
2 is formed. A reflection surface (reflection end surface) is formed at one end 1a of the fiber laser light guide 1 by mirror polishing or gold plating, and an output window of a laser light 52 generated by excitation of the laser active material is formed at the other end 1b. (Light-emitting end face). The excitation light introducing member 3 is optically connected to one end 21a of the light guide member 21 forming the excitation light guide 2, and the excitation light 51 is introduced therefrom. The other end 21b has a reflective surface (reflective end surface) by mirror polishing or gold plating.
Is formed to prevent the excitation light introduced into the excitation light guide 2 from passing through the other end 21b to the outside. The laser light guide 1 is spirally wound on the outer surface of the excitation light guide 2 while being in optical close contact over a predetermined length range.

The excitation light introducing member 3 is formed by using a ribbon-shaped light guiding member, one end 3a of which is disposed on the side of the excitation light source 41 and the other end 3b of which is a light guiding member forming the excitation light light guide 2. The end faces of the end 21 are optically connected to each other. This excitation light introducing member 3
Is made of the same material (quartz glass) as the light guide member 21 forming the excitation light guide 2. Further, the cross-sectional shape and the size are also formed in the same manner, and the end faces (3b and 21a) are brought into contact with each other without any excess or shortage. The excitation light source 41 is configured using an LD element array (or LD bar) in which a large number of semiconductor laser elements (LD elements) are arranged in a line, and conforms to the end face shape of one end 3a of the ribbon-shaped excitation light introducing member 3. Therefore, the excitation light 51 is emitted in an intensity distribution state spreading linearly in the width direction. The excitation light 51 is made incident on one end 3a of the excitation light introducing member 3 via a condensing optical system 42 configured using a cylindrical lens or the like. This allows the excitation light 51 from the excitation light source 41 to be incident on the one end 3a of the excitation light introduction member 3 with high efficiency. The excitation light 3 incident on the excitation light introducing member 3 is incident on one end 21 a of the light guide member 21 forming the excitation light guide 2 from the other end 3 b of the introduction member 3. The excitation light 51 incident on the excitation light guide 2 is spirally circulated in a state of being confined in the excitation light guide 2, thereby propagating over the entire light guide 2. Let me do. Most of the pumping light confined in the pumping light guide 2 is finally distributed and introduced into the laser light guide 1 that is in optical contact with the surface of the pumping light guide 2, and the laser is activated. Becomes absorbed by the substance.

In the laser device manufactured as described above,
First, by forming the laser light guide 1 with a flexible optical fiber that forms a long and continuous waveguide structure,
The following effects can be obtained. That is, by appropriately selecting the diameter of the core portion of the optical fiber constituting the laser light guide 1 and the difference in the optical refractive index between the core portion and the cladding portion, the transverse mode of laser oscillation can be relatively easily controlled. Can be Further, by confining the light in the optical fiber at a high density, the interaction between the laser active substance and the light can be enhanced. Furthermore, since the interaction length of laser excitation can be increased by increasing the length of the optical fiber, it is possible to generate spatially high-quality laser light with high efficiency. Therefore, high-quality laser light can be obtained relatively inexpensively.

Furthermore, the following effects can be obtained in addition to the above-mentioned effects by the configuration in which the excitation light 51 is confined by the excitation light guide 2 so as to be distributed and introduced into the laser light guide 1. That is, the excitation light 51 can be introduced in a state of being distributed in the longitudinal direction not from the end face of the laser light guide 1 but from its side. That is, the excitation light guide 2 propagates the excitation light 51 introduced from the excitation light source 41 via the excitation light introduction member 3 while confining the excitation light 51 by internal reflection. When the body 1 is wound and the laser light guide 1 is brought into optical contact with the surface of the excitation light guide 2 over a predetermined length range, the excitation light confined inside the excitation light guide 2 passes through the contact portion. The laser beam enters the laser light guide 1. In this way, the laser active substance contained in the laser light guide 1 can be efficiently excited by the excitation light distributed and introduced into the laser light guide 1.

The excitation light guide 2 is formed by molding or machining an optical material such as glass by winding a thin plate-shaped flexible light guide member while imparting a shape with a support and keeping the shape. The excitation light guide 2 having a thin structure, which has been difficult to form by the conventional method, can be formed relatively simply and with high flexibility at low cost. For example, in the case of a tubular excitation light guide 2, in order to reduce the propagation loss of the excitation light, it is necessary to reduce the wall thickness of the circular tube to at least 1 mm or less, preferably to 500 μm or less. Also, such a thin structure can be easily realized without depending on expensive machining. Thus, the pumping light guide 2 having a light guiding structure that can efficiently introduce the laser light into the laser light guide while confining the pumping light with low loss can be formed relatively easily and at low cost.

As described above, according to the above-described method of the present invention, the advantage of the method of distributing and introducing pumping light into a laser light guide having a long structure such as a laser fiber, for example, the transverse mode of laser oscillation is simple. Can generate high quality spatially high quality laser light with high efficiency,
A laser device capable of increasing the output efficiency or efficiency of laser light by increasing the excitation efficiency of a laser active substance performed through an excitation light guide while taking advantage of such advantages can be provided at low cost. . In addition, by irradiating the processing target with the laser beam 52 output from the laser device, a high-efficiency, high-output laser processing device can be provided.

FIG. 5 shows another embodiment of the excitation light guide 2 produced by the present invention. Excitation light guide 2 shown in FIG.
Are a plurality of (three) ribbon-shaped light guide members 21, 21, 21
The support 6 in a set state in which
It is formed into a single tubular shape by spirally winding it up. In this excitation light guide 2, each light guide member 2
Excitation light is introduced from one end 21a, 21a, 21a or both ends 21a, 21a, 21a and 21b, 21b, 21b of 1, 21, 21. Excitation light is applied to both ends 21a, 21a, 2
1a and 21b, 21b, 21b, the two ends 21a, 21a, 21a and 21b, 21b
The excitation light introducing member 3 as shown in FIG. 1, for example, is connected to each of b and 21b. When the excitation light is introduced only from one end 21a, 21a, 21a of each light guide member 21, 21, 21, 21, the other end 21b, 21b, 21b is used.
Are formed with reflection surfaces (reflection end surfaces) of the excitation light. In this way, the plurality of light guide members 21, 21, 21 are assembled to form one excitation light guide, and each light guide member 2
By introducing the pumping light to 1, 2, 21 respectively, it becomes possible to introduce more pumping light.
Therefore, the excitation light guide 2 is suitable for forming a particularly high-output laser device such as a laser device used in a laser processing device. In this case, the plurality of light guide members 21, 21 and 21 are wound such that no gap is formed therebetween, and the width ends adjacent to each other are optically connected to each other. ,
21 can be treated as one wide light guide member.

FIG. 6 shows an example of the structure of a support used in the present invention. When the light guide member 21 is wound to form the excitation light guide 2 having a predetermined shape, the work can be facilitated by using the support 6 according to the desired shape.
The support 6 can have both the function of shape preservation and the reinforcement of the structure formed by winding the light guide member 21, but in addition, the function as a radiator that actively promotes heat release. Can also have. (A) of FIG.
(B) shows an example of the configuration of the support 6 provided with a function as a radiator. The support 6 shown in FIG.
For example, by using a good heat conductor that exhibits a higher thermal conductivity than glass, which is the main constituent material of the excitation light guide, such as aluminum and copper, and by forming a hollow cylindrical shape with both ends open The heat radiation effect is increased by increasing the heat radiation area and promoting the flow of a cooling medium such as air. Reference numeral 61 denotes a hollow portion of the hollow cylinder. The support 6 shown in FIG. 3B is formed in a cylindrical shape having good heat conductivity and a large heat absorption volume, and a plurality of heat radiation holes 62 penetrating in the axial direction of the cylinder are arranged in a substantially uniform distribution. By forming, the heat dissipation effect is further enhanced by increasing the heat dissipation area and promoting the flow of the cooling medium such as air. In order to enhance the heat radiation effect of the support 6 by means other than the above, a structural heat radiation means such as a heat pipe may be used.

FIG. 7 shows another example of the structure of the support used in the present invention. The support 6 shown in the figure has a groove 63 provided in a portion where the light guide member 21 is wound, and
Workability and reproducibility when winding the light guide member 21 can be improved. In addition, as described later, by forming a structure for confining the light leaking from the excitation light guide 2 into the groove 63, the efficiency of introducing the excitation light into the laser light guide can be increased.

FIG. 8 schematically shows a second embodiment of the laser device constructed according to the present invention. The laser device of this embodiment is configured using the support shown in FIG.
The support 6 has a groove 63 at a portion where the light guide member 21 is wound. A coating layer 64 that forms a highly reflective surface is formed on the inner side surface (bottom and side surfaces of the groove) of the groove 63.
The reflection coating layer 64 is formed by coating a resin having a refractive index (about 1.38) lower than that of quartz glass uniformly after applying gold plating. The ribbon-shaped light guide member 21 is wound around the guide groove 63 to form the excitation light guide 2. A laser light guide (laser fiber) 1 composed of a core portion 11 and a clad portion 12, both of which are made of quartz glass, is wound around the outer surface of the excitation light guide 2. The winding point of the laser light guide 1 has a refractive index (about 1.46) substantially the same as that of quartz glass.
Is applied in such a manner as to embed the laser light guide 1. The outside of the laser light guide 1 is covered with a cover member 65. The reflection coating layer 64 is also formed on the inner surface of the cover member 65.

In the laser device configured as described above, since the refractive index of the resin 22 covering the laser light guide 1 is substantially the same as that of quartz glass, the inside of the excitation light guide 2 is confined. The pumping light that is propagated can be introduced into the cladding portion 12 of the laser light guide 1 with high probability via the resin 22. Then, the laser active substance contained in the core portion 11 can be efficiently excited through the clad 12 to perform laser oscillation or amplification. Further, the guide groove 63 and the cover member 65
Of the excitation light guide 2 formed by winding the light guide member 21 because the reflection coating layer 64 is formed on both
Then, the entire laser light guide 1 wound while being in optical contact with the excitation light guide 2 can be formed in an optically confined state. Thereby, the leakage of the excitation light can be blocked to improve the excitation efficiency.

FIG. 9 schematically shows a third embodiment of the laser device constructed according to the present invention. The laser device shown in FIG. 1 uses the excitation light guide 2 having the same structure as that shown in FIGS. 1 to 4. Excitation light 5 from both ends 21a, 2b of the ribbon-shaped light guide member 21 forming
1,51 are introduced. As a result, more pumping light 51 can be introduced, but this has the effect of making it easier to increase the output of the laser light 52, for example.

FIG. 10 schematically shows a fourth embodiment of the laser device constructed according to the present invention. The laser device shown in the figure also uses the excitation light guide 2 having basically the same structure as that shown in FIGS. 1 to 4, but in this embodiment,
Ribbon-shaped light guide member 2 forming the excitation light guide 2
It is described that the excitation light 51 is circulated and reproduced from the other end 21b to the one end 21a. The excitation light guide 2 has a tubular shape, and is formed by spirally winding a ribbon-shaped light guide member 21. The introduction of the excitation light into the excitation light guide 2 is performed from the one end 21a of the light guide member 21 forming the excitation light guide 2. Excitation light that spirals and reaches the other end 21b of the light guide member is re-introduced and circulated to the one end 21a. To this end, a light returning member 32 is connected between the other end 21b and the one end 21a of the light guide member 21. This return light guide member 32
Is formed in a flexible ribbon shape, and one end 32a of the
The surface is connected to the other end 21b surface of the light guide member 21, and the other end 32b is connected to the one end 21a surface of the light guide member 21 to form a dense optical bonding state. In this case, two light guide ends of the excitation light introduction member 3 and the return light guide member 32 are connected to the one end 21a side of the light guide member 21. Therefore, the excitation light introducing member 3 and the return light guiding member 3
2 are each formed in a ribbon shape, and are formed in a tapered shape such that the ribbon width is continuously narrowed from one end to the other end. Thereby, both members 3, 32
The other ends 3b and 32b are aligned with the one end 21a of the light guide member 21 in a state where they are arranged in the width direction.

In the figure, one end 21a of the light guide member 21
Is distributed and introduced into the laser light guide 1 in the process of propagating while being confined inside the light guide member 21, and a part thereof reaches the other end 21 b of the light guide member 21. The excitation light that has reached the other end 21b is propagated from one end 32a of the return light guide member 32 to the other end 32b, and is again introduced into the one end 21a of the light guide member 21. With such a circulation-reproduction-type light guide structure, the excitation light 51 once introduced into the excitation light guide 2 is confined in an endless optical path and repeatedly circulated. As a result,
The introduction of the excitation light from the excitation light guide 2 to the laser light guide 1 is longer than the length of the actual contact between the two (2 and 1).
The same effect can be obtained as if it were distributed over a much longer range. That is, the effect of effectively expanding the range of introduction of the excitation light from the excitation light guide 2 to the laser light guide 1 is obtained. Thereby, even if the winding length of the laser light guide 1 is shortened or the surface area of the excitation light guide 2 is reduced, the excitation light is propagated while being confined in the excitation light guide 2; The distribution of the confined excitation light into the laser light guide 1 can be efficiently performed. Therefore, a high-output laser beam can be obtained with high efficiency using a simple and low-cost configuration.

FIG. 11 shows still another embodiment of the excitation light guide. The excitation light guide 2 shown in the figure is formed in a substantially circular tube shape by winding a single sheet-like light guide member 21 having flexibility around the body of the cylindrical support 6 only once. . In this case, the sheet-shaped light guide member 21 has both ends 21a, 2a.
The end faces 1b are slightly obliquely wrapped so that the end faces 1b abut against each other, and the abutting surfaces 21c are slightly shifted in the width direction and are staggered. In other words, the sheet-shaped light guide member 2 has the offset surfaces 211a, 211b on the abutting surfaces 21c of both ends 21a, 21b.
It is wound so as to occur. This offset surface 21
Excitation light can be introduced at 1a and / or 211b. The width of the offset surfaces 211a and 211b can be arbitrarily set according to the direction in which the sheet-like light guide member 21 rotates. That is, the offset surface 21
The width lengths of 1a and 211b vary depending on the magnitude of the inclination of the support 6 in the circumferential direction with respect to the cylindrical axis. That is, the excitation light introduction width at the offset surfaces 211a and 211b can be arbitrarily set according to the manner in which the sheet-like light guide member 21 rotates. When it is desired to introduce more pump light to obtain high output, the offset surface 211 is required.
In order to increase the width length of the a and 211b, it is possible to cope with this by making the circuit wrap around at a relatively steep inclination. Also,
If it is desired to confine the excitation light efficiently, it can be dealt with by making the circumference of the offset surface 211a, 211b with a relatively gentle inclination so that the width length becomes small.

The introduction of the excitation light is performed by the sheet-like light guide member 2.
One or both of the offset surfaces 211a and 211b formed on the one end 21a and the other end 21b of the device 1 may be used, and may be selected as appropriate according to a target laser output level or the like. Offset surface 211a and / or 21
The introduction of the excitation light into 1b is performed in such a direction that the excitation light propagates in the axial direction while circulating in the cylindrical excitation light guide 2 in the circumferential direction. For this purpose, the excitation light is made to enter at an angle slightly inclined in the axial direction with respect to the circumferential direction. Thereby, the pumping light introduced into the pumping light guide 2 propagates throughout the pumping light guide 2 while spiraling around the pumping light guide 2.
By doing so, the laser light guide 1 is separated from the excitation light guide 2.
The effect of effectively expanding the distribution introduction range of the excitation light to the substrate is obtained. Butt surface 2 of sheet light guide member 21
Regarding 1c, both a configuration in which the excitation light is optically continuous so that the excitation light can move back and forth, and a configuration in which the excitation light is reflected at the abutting surface to reverse the traveling direction are possible. When the butting surface 21c is made optically continuous, the butting surface 21c is fused or bonded with a resin (adhesion or mold) to form a mechanically and optically connected state. The abutment surface 21c
Can be formed also by using a ribbon-shaped light guide member 21. That is, it can also be formed by spirally winding the ribbon-shaped light guide member 21 to form a circular tube, and joining adjacent portions of the wound light guide member 21 by fusion or resin. .

FIG. 12 is a cross-sectional view schematically showing a configuration example of the sheet-like light guide member. For example, the sheet light guide member 21 for constituting the excitation light guide 2 shown in FIG. 11 may be constituted by a single member as shown in FIG. ) Or (c), a plurality of light guide members 210 may be assembled in a state of being arranged in the width direction. (B) is an example in which one sheet-like light guide member 21 is formed using a plurality of ribbon-like light guide members 210, and (c) is a sheet-like light guide member using a plurality of linear light guide members 210. An example in which the optical member 21 is configured will be described. The light guide members 210 are mechanically and optically joined together by fusion or resin (adhesion or molding).

FIG. 13 shows an application example of the excitation light guide shown in FIG. In the figure, (a) shows the excitation light guide 2
(B) is a plan development view of the excitation light guide 2. For example, the tubular excitation light guide 2 shown in FIG.
By joining buttings 1b, a kind of annular structure is formed. In the excitation light guide 2 having such an annular structure, both ends 21 a and 21 b of the sheet-like light guide member 21 are provided.
Are aligned in such a manner that offset surfaces 211a and 211b are generated, and the abutting surfaces 21c are optically continuous by fusion or resin (adhesion or molding) or optical contact (optical contact), so that in FIG. As indicated by the arrow, a light guide structure that circulates the entire inside of the excitation light guide 2 while spirally propagating the excitation light 51 introduced from the one offset surface 211a can be formed. In order to form such a light guide structure, the excitation light is made to enter at an angle slightly inclined in the axial direction with respect to the circumferential direction of the excitation light guide 2.
Accordingly, the excitation light introduced into the excitation light guide 2 is
As shown by arrows in the figure, the light propagates throughout the light guide 2 while spirally circulating the excitation light guide 2 over a long distance. By doing so, the effect of effectively expanding the distribution introduction range of the excitation light from the excitation light guide 2 to the laser light guide 1 is obtained.

FIG. 14 shows another example of the light guide structure formed by using the excitation light guide shown in FIG. In the figure, (a) and (b) show plan development views of the tubular excitation light guide 2, respectively. (A) of the same figure shows that both ends 21 a and 21 b of the sheet-shaped light guide member 21 are
a and 211b are abutted so as to generate, and the abutting surface 21c is made an optical reflection surface by mirror polishing or gold plating. The incidence of the excitation light 51 is
As shown by the arrow in the figure, one offset surface 211a
From the circumferential direction (winding direction) at an angle slightly inclined in the axial direction. Thereby, as shown by the arrow in the figure,
The excitation light introduced into the excitation light guide 2 is caused to travel along the winding direction of the light guide member 21 forming the excitation light guide 2, and the traveling direction is periodically reflected and inverted. A light guide structure that circulates the entire inside of the excitation light guide 2 is formed. Such a light guide structure can increase the optical path length of the excitation light 51 inside the excitation light guide 2, and thus can obtain a high confinement efficiency with respect to the size of the excitation light guide 2. Is obtained.
Further, an effect of effectively expanding the range of introduction of the excitation light from the excitation light guide 2 to the laser light guide 1 can be obtained.

FIG. 7B is a diagram similar to FIG.
The offset surface 211b located at the exit of the excitation light 51 is covered with an optical reflection surface. In this case, the excitation light 51 introduced from one of the offset surfaces 211a traverses the entire inside of the excitation light guide 2 and reaches the other offset surface 211b as shown by the arrow in the drawing, so that the traveling direction is reversed. So that the light can be circulated in the excitation light guide 2 again. Accordingly, the optical path length of the excitation light 51 inside the excitation light guide 2 can be greatly increased, so that even if the size of the excitation light guide 2 is reduced, the excitation light 51 is confined with high efficiency. Can be made. Further, since the range of introduction of the excitation light from the excitation light guide 2 to the laser light guide 1 can be effectively expanded, the excitation light can be efficiently introduced even if the laser light guide 1 is shortened. be able to.

FIG. 15 schematically shows a fifth embodiment of the laser device constructed according to the present invention. The laser device shown in the figure is configured using an excitation light guide 2 having a ring-shaped closed structure. The excitation light guide 2 is formed in a ring-shaped closed structure by completely overlapping and butting both ends 21a and 21b of the sheet-shaped light guide member 21 so as not to generate an offset surface. As shown in the drawing, the introduction of the excitation light 51 into the excitation light guide 2 having such a structure is efficiently performed by the ribbon-shaped excitation light guide member 3 having the other end 3b formed in a sharply tapered shape. Can be. The ribbon-shaped excitation light introducing member 3 is formed by stretching or drawing quartz glass into a ribbon shape.
Excitation light is introduced into a through the condensing optical system 42 from the excitation light source 41. The other end 3b is cut into a sharply tapered shape, and the tapered cut surface 3c is brought into optical close contact with the opening end surface of the tubular excitation light guide 2. As a result, the excitation light 51 transmitted through the introduction member 3
Can be smoothly introduced into the excitation light guide 2 from the tapered cut surface 3c.

FIG. 16 schematically shows a sixth embodiment of the laser device constructed according to the present invention. The laser device shown in the figure includes both ends 21 a and 21 b of a sheet-like light guide member 21.
The optical fiber 31 is used to introduce the excitation light 51 into the annular excitation light guide 2 formed by abutting. In the figure, an excitation light source 4 of a laser device is shown.
The output light of the LD collective element (LD bar or LD array) forming 1 is guided to the excitation light guide 2 by the optical fiber 31 for each LD element. In this case, each of the optical fibers 31, 31,. . . And the light emitting surface of each LD element must accurately match each other. For this reason, each fiber 31, 31,. . . Are fixed using a positioning jig 7. Although not shown in detail, the positioning jig 7 is formed by arranging guide grooves having a 90-degree V-shaped cross section at a constant pitch, and the optical fibers 31, 31,. . . Are positioned at respective ends.

In the embodiment shown in the figure, the excitation light guide 2 is, as shown in FIG. 6 to FIG. What is formed in the shape of a substantially circular tube by abutting end faces while leaving 211a and 211b is used. Both of the two offset surfaces 211a and 211b are used as ports for introducing pump light. The other end of the optical fiber 31 is fusion-spliced to each of the offset surfaces 211a and 211b so that excitation light is introduced.

FIG. 17 schematically shows a seventh embodiment of the laser device constructed according to the present invention. The laser device shown in the figure is a flat disk-shaped excitation light guide 2.
It is configured using Disc-shaped excitation light guide 2
Can be formed relatively easily by spirally winding narrow ribbon-shaped or linear light-guiding members 21 on the same plane. When this disk-shaped excitation light guide 2 is used, for example, as shown in FIG. Can be configured.

As described above, the excitation light guide 2 can be formed into a shape other than a circular tube, for example, a disk shape. Is possible. In general, quartz glass is suitable for the material of the light guide member 21 described above. However, this is not necessarily quartz glass, and any material that is transparent to excitation light may be used. Resins and plastics can also be used. Although the ribbon-shaped light guide member 21 has a uniform width and thickness, a light guide member 21 having a width and a thickness that vary according to the shape of the support 6 may be used. The means for introducing the excitation light into the laser light guide 2 may be a means using a prism or a diffraction grating other than the means using the ribbon-shaped member 3 or the optical fiber 31 described above.

FIG. 18 shows another embodiment of the method for manufacturing a laser device according to the present invention. In the figure, (a) and (b)
(C) is a cross-sectional view of a laser device configured according to the present invention. According to the present invention, (1) a first light guide member having a predetermined shape is formed by winding a thin plate-shaped flexible light guide member while imparting and maintaining the shape with a support.
And (2) making the predetermined length range of the laser light guide come into optical contact with the excitation light guide directly or indirectly via an optical medium transmitting the excitation light. Before or after the excitation light guide is formed,
The second step of winding or folding the laser light guide is performed. Various forms of laser devices can be manufactured depending on the order of the two steps, the combination thereof, the mode thereof, and the like. For example, the following aspects are possible.

That is, FIG. 7A shows an example of the configuration of a laser device manufactured by performing the first step after the second step. This laser device has a structure in which the laser light guide 1 is sandwiched between the support 6 and the excitation light guide 2,
With such a structure, for example, it becomes easy to efficiently confine the excitation light between the support 6 and the excitation light guide 2, and the support 6 efficiently absorbs the heat generated from the laser light guide 1. And the heat radiation effect can be enhanced. FIG. 2B shows a configuration example of a laser device manufactured by performing the second step after the first step and then performing the first step. This laser device has a structure in which the laser light guide 1 is sandwiched between the two excitation light guides 2 and 2. The effect is obtained that the introduction can be performed efficiently from both sides. FIG. 3C shows a configuration example of a laser device manufactured by changing the mode of the first step and the mode of the second step. In this laser device, the winding of the light guide member 21 and the winding of the laser light guide 1 forming the excitation light guide 2 are performed on the inner surface of the hollow cylindrical support 6. In the laser device thus manufactured, for example, the inside of the hollow cylindrical support 1 is closed from the outside,
By forming a high-reflection surface on the entire inner surface, an effect of increasing the laser excitation efficiency by confining light leaked from the excitation light guide 2 or the like into the hollow interior can be expected.

FIG. 19 shows a first embodiment of the optical contact state between the laser light guide and the excitation light guide. As shown in FIG. 1A, even when the laser light guide 1 is simply in contact with the surface of the excitation light guide 2, the laser light guide 1 can be in an optical contact state in which excitation light can flow between the two. . Further, as shown in (b), by partially fusing the clad portion 12 of the laser light guide 1 to the excitation light guide 21, an optical contact state having a high coupling density can be obtained. . FIG. 20 shows a second embodiment of the optical contact between the laser light guide and the excitation light guide. (A)
(B) As shown in (c), the laser light guide 1
Can be brought into optical contact with the excitation light guide 2 indirectly via the optical medium 23 that transmits the excitation light. As the optical medium 23, for example, a resin is used. In this case, the optical medium 23 is (a) interposed as a coating layer on the surface of the excitation light guide 2, (b) partially embeds the laser light guide 1, (c) the entire laser light guide 1. Embedded, etc. are provided. As the optical medium 23, a material having a refractive index equal to or smaller than the refractive index of the clad portion of the laser light guide, and having a refractive index equal to or larger than the refractive index of the excitation light guide member is suitable. . As described above, the typical embodiments of the present invention have been described based on the drawings. However, the present invention includes the following embodiments including the above-described embodiments. (1) An excitation light guide having a predetermined shape is formed by winding a thin plate-shaped flexible light guide member while imparting and maintaining the shape of the support with a support, and thus forming the excitation light guide. A method for manufacturing a laser device in which excitation light is distributed and introduced into a laser light guide using a body, and has the following features. That is, as the light guide member, for example, a member formed in a fiber shape, a ribbon shape, or a sheet shape is used, and is wound around a support to form a predetermined shape. Form a light body. As a laser light guide, a fiber-shaped laser medium having a clad part and a core part and containing a laser active substance in the core part, so-called laser fiber, is formed. The length of at least a part of the laser fiber is brought into contact with the excitation light guide directly or indirectly via an optical medium, and the active substance is excited by the excitation light incident in a distributed manner through the contact portion. So that

(2) In the above laser device, the shape of the excitation light guide is given by the shape of the support around which the light guide member forming the light guide is wound. That is, the excitation light guide is formed using the support as a matrix. This support,
A cylindrical shape, a conical shape, a truncated conical shape, a barrel shape, or a wound shape, such as a shape whose cross-sectional shape changes in the central axis direction, or a disk shape, a fiber shape,
An excitation light guide having a predetermined structure can be formed by efficiently winding a light guide member such as a ribbon or a sheet.

(3) In the above laser device, the refractive index of the light guide member forming the excitation light guide is made substantially equal to or smaller than the refractive index of the cladding of the laser light guide (laser fiber). By selecting the refractive indices of the light guide member and the laser light guide as described above, the excitation light propagating in the light guide member can easily enter the clad portion of the laser light guide. Thereby, the excitation efficiency of the laser active substance contained in the core part can be increased. Also, by using the same material for both, the optical properties such as the refractive index can be made uniform, and the thermal and mechanical properties can be made the same. Can be prevented.

(4) In the above laser device, a substance having a smaller refractive index than the light guide member is provided between the light guide member forming the excitation light guide and the support around which the light guide member is wound. Is provided. Since there is a layer having a small refractive index between the light guide member and the support, light leakage to the layer having a small refractive index can be suppressed. Further, since the light guide member does not come into direct contact with the substance forming the support, it is possible to prevent unnecessary light absorption from occurring at the support. As a result, more excitation light can be propagated to the laser light guide side, and the excitation efficiency of the laser active substance contained in the light guide can be increased.

(5) In the above laser device, a means for reflecting at least the excitation light is provided on the surface of the support. Since the excitation light reflecting means is provided on the surface of the support around which the light guide member is wound, even if the excitation light is emitted from the light guide member to the support side, the excitation light is guided by the laser light guide. It can be reflected back to the body side. This allows
Excitation light can be used without waste.

(6) In the above laser device, at least a part of the excitation light guide and the laser light guide that is in contact with the surface of the excitation light guide are covered by means capable of reflecting the excitation light. This makes it possible to use the excitation light leaked from the excitation light guide or the laser light guide again for excitation.

(7) In the above laser device, the excitation light is made to enter from the end face of the fiber, ribbon or sheet light guide member. It is necessary to provide a means for newly entering light, for example, a prism part for incidence, on the light guide member by causing the excitation light to enter from the end face of the fiber, ribbon, or sheet light guide member. Disappears. Further, the probability that the once-entered excitation light escapes from the entrance to the outside can be suppressed low. Thereby, the waste of the excitation light can be reduced.

(8) In the above laser device, a fiber-, ribbon- or sheet-like excitation light introducing member having flexibility is provided on the side surface or surface of the fiber-, ribbon- or sheet-like light guide member. The fusion splicing is performed, and the excitation light is introduced into the excitation light guide by the fusion spliced excitation light introducing member. This makes it possible to introduce the excitation light with low loss. Further, by using a flexible fiber-, ribbon-, or sheet-like excitation light introducing member, the degree of freedom of connection with the excitation light source can be increased.

(9) In the above laser device, the excitation light guide is formed by a plurality of light guide members. As the light guide member (excitation light guide member), a fiber shape, a ribbon shape,
Alternatively, a sheet-shaped member is used. By forming the excitation light guide using a plurality of light guide members, the degree of freedom of the structure of the excitation light guide is increased, and the excitation light can be incident from both end faces of the plurality of light guide members. Therefore, more excitation light can be used. This facilitates the realization of a high-output laser fiber device.

(10) In the above laser device, a guide groove for guiding the fiber laser light guide is provided in advance so as to obliquely cross the fiber, ribbon or sheet excitation light guide member. By providing a guide groove in accordance with the winding pitch of the laser light guide (laser fiber) on the surface of the fiber, ribbon, or sheet light guide member forming the excitation light guide, The laser light guide can be accurately and stably wound at a predetermined pitch regardless of the winding pitch or without being disturbed in the winding direction or the like.

(11) In the above laser device, a circular excitation light guide is formed by winding a sheet-like light guide member in an annular shape and abutting both end surfaces thereof.
The butted surfaces are fusion-spliced. By abutting the two end faces of the sheet-shaped light guide member and fusing them together, the abutted faces can be made optically smooth and continuous. An excitation light guide that can be performed is made possible.

(12) In the above laser device, a circular excitation light guide is formed by winding a sheet-like light guide member in an annular shape and abutting both end surfaces thereof.
A high reflection film is formed on the abutting surface. By providing the high reflection film on the abutting surface, the excitation light is turned back, so that it is possible to effectively follow a longer optical path length before reaching the end of the sheet. This makes it possible to reduce the size of the excitation light guide.

(13) In the above laser device, a fiber-shaped, ribbon-shaped, or sheet-shaped light guide member is wound annularly and its both end faces are joined to form a substantially tubular excitation light guide body. Both end surfaces of the light guide member are entirely or partially butted, and the butted portion is optically coupled. By optically coupling both end faces of the light guide member, the excitation light once incident on the excitation light guide is distributed from the excitation light guide to the laser light guide and absorbed by the laser active material. Until that time, the pump light continues to circulate while traveling in the same direction in the excitation light guide. As a result, the excitation light that has entered the excitation light guide once does not leak out from the entrance, and is effectively used for exciting the laser active substance. Furthermore, it is possible to shorten the length of the laser light guide (laser fiber) by increasing the number of rounds of the excitation light, thereby reducing the loss in the laser light guide and improving the laser fiber. Each of these costs can be reduced.

(14) In the above laser device, the support around which the excitation light guide member is wound is made of a material having better heat conductivity or heat radiation property than the laser light guide. The heat generated by absorption of the excitation light in the excitation light guide can be efficiently released, thereby improving stability and reliability.

(15) In the above laser device, after forming the excitation light guide using the support, the support is removed to form the excitation light guide without the support. Removal of the support allows the excitation light guide to have structural flexibility or flexibility, thereby providing advantages such as, for example, easier storage of the excitation light guide.

(16) In the above laser device, a groove for winding the light guide member is provided on the surface of the support. Due to the grooves, the excitation light guide can be formed more stably with good reproducibility, and the excitation light leaked from the side surface of the excitation light guide is confined without leaking to the outside, and finally the laser light guide is formed. It can be introduced and used for exciting the laser active substance. Thereby, the utilization efficiency of the excitation light can be increased.

(17) In the above laser device, the thickness of the wall portion of the excitation light guide formed by the fiber, ribbon, or sheet light guide member is formed to be 500 μm or less. By setting the thickness of the excitation light guide to be equal to or less than the above value, it becomes possible to propagate the excitation light while confining it with low loss and to introduce it into the laser light guide.

(18) In the above laser device, the excitation light guide formed of the fiber, ribbon or sheet excitation light guide and the fiber laser light guide are alternately stacked in layers. Form the structure. By alternately stacking the layers, the contact amount between the excitation light guide and the laser light guide is increased, so that more excitation light can be introduced from the excitation light guide to the laser light guide. Thus, it is easy to realize a high-output fiber laser device.

(19) In the above laser device, the laser light guide wound on the excitation light guide may have a refractive index equal to or smaller than the refractive index of the cladding portion of the laser light guide.
In addition, it is covered with an optical medium having a refractive index equal to or greater than the refractive index of the excitation light guiding member. By being covered with the optical medium as described above, the excitation light is transmitted from the excitation light guide to the laser light guide not only from the surface where both are in direct contact, but also through the optical medium. Become. This makes it possible to excite the laser active substance more efficiently. In addition, by selecting the refractive index as described above, utilizing the property that light propagates in the direction of higher refractive index, the pumping light is transmitted from the pumping light guide to the cladding part and the core part of the laser fiber. Can be efficiently propagated.

(20) In the above laser device, a fiber-shaped, ribbon-shaped, or sheet-shaped light guide member forming the excitation light guide is manufactured by a drawing method or extrusion molding. The fiber-shaped, ribbon-shaped, or sheet-shaped light guide member can be easily manufactured in a desired width or thickness in a large amount by a drawing method or extrusion molding.

(21) In the above laser device, a fiber-shaped, ribbon-shaped or sheet-shaped excitation light-guiding member forming the excitation light-guiding member is produced by a sputtering method, a flame deposition method, or the like. By manufacturing the light guide member by the above method, the degree of freedom in selecting a material that can be used as the light guide member is increased, and the control range (or selection range) of the characteristics of the excitation light guide can be expanded. .

(22) In a laser processing apparatus having a laser light source, means for guiding laser light generated from the laser light source to a processing object, and means for irradiating the processing object with the guided laser light, The laser device using a laser light guide having a shape of a circle is used as the laser light source. Thereby, an optical fiber can be easily connected as a means for guiding the laser light. In addition, since a laser beam having high output and good condensing properties can be used for processing, efficient fine processing can be performed.

(23) The excitation light is introduced into the excitation light guide at an incident angle at which the excitation light circulates or circulates through the entire light guide. For example, in the case of an excitation light guide formed in a tubular shape, the excitation light is incident at a low angle that is slightly inclined in the axial direction with respect to the circumferential direction of the light guide. As a result, the excitation light can be efficiently confined in the excitation light guide, and even if the excitation light guide is relatively small in size, the laser light can be optically brought into contact with the excitation light guide. Even if the light body is relatively short, the distribution of the excitation light into the laser light guide can be efficiently introduced.

[0071]

The present invention will be described below in more detail with reference to typical examples. (Example 1) In Example 1, a laser device was manufactured using the method shown in FIG. The outer diameter 9c as the support 6
m, inner diameter 6 cm, length (cylinder length) 7 cm aluminum cylinder with gold coating (plating) on the outer periphery, and aluminum cylinder 10 mm outer diameter, 9 cm inner diameter, 7 cm length (cylinder length) The outer periphery was provided with a gold coat (plated). In addition, a ribbon-shaped light guide member having a width of 5 mm and a thickness of 500 μm was prepared as the light guide member 2. The ribbon-shaped light guide member 21 was produced by drawing and stretching quartz glass. The light guide member 21 was wound around each of the supports 6 while irradiating a CO 2 laser to produce the cylindrical excitation light guide 2. The laser for irradiation is a CO2 laser device 82 with a laser output of 500 W.
Generated using. A laser beam having a beam diameter of 13 mm output from the laser device 82 is doubled by a beam expander 83, bent at a right angle by a mirror 84, and then collected linearly by a cylindrical lens 85 having a focal length of 150 mm. The light was applied to the wound portion of the ribbon-shaped light guide member 21 via the mask plate 86. Mask plate 8
6, a slit having an opening of 1 mm × 5.5 mm is formed, and the laser light beam 81 condensed in a linear shape is locally irradiated on the light guide member 21 of the winding portion through the slit. did. The winding speed is about 1 in linear speed
00 mm / sec. When the light guide member 21 was wound around the support 6 by the method described above, the shape after the winding could be stably maintained without being broken in the middle and without being separated after the winding. In this embodiment, CO 2
Although the winding is performed while irradiating the two-laser light beam 81, annealing may be performed by irradiating the whole with a CO2 laser after the winding.

(Example 2) Under the conditions of Example 1, the light guide member 21 was wound around the support 6 under the condition that there was no laser irradiation at the time of winding. After this winding, the entirety of the light guide member 21 wound around the support 6 using the optical system (81 to 85) obtained by removing the mask plate 86 from the optical system (81 to 86) of the first embodiment. Laser irradiation was performed. This irradiation was performed twice while rotating the whole. As a result, substantially the same effects as those of the first embodiment were obtained.
In addition, due to the effect of annealing treatment that removes internal stress,
An optically very uniform excitation light guide 2 could be obtained.

Example 3 The entire light guide member 21 wound around the support 6 in Example 1 was annealed by the method of Example 2. Thereby, the winding operation could be performed smoothly and stably, and the optically very uniform excitation light guide 2 could be obtained.

(Embodiment 4) In Embodiment 4, Embodiments 1 to 3 will be described.
A fiber laser device as shown in FIG. 4 was produced using the excitation light guide 2 produced in the above. That is, FIG.
As shown in FIGS. 1 to 3, a ribbon-shaped light guide member 2 made of glass is wound around the outer periphery of a cylindrical support 6 to form the excitation light guide 2, and as shown in FIG. A laser device was fabricated by winding a fiber-shaped laser light guide (laser fiber) 1 around the surface of the body 2. As the excitation light source 41, an LD element array having an oscillation wavelength of 0.8 μm and a total output of 30 W was used. As the support 6, an aluminum cylinder having an outer diameter of 10 cm, an inner diameter of 9 cm, and a length of 7 cm was used. This support 6
Is uniformly coated (coated) with a resin having a refractive index of about 1.38. The excitation light guide member 21 has a width of 10 m by stretching quartz glass by drawing.
m, a ribbon formed with a thickness of 250 μm was used. The ribbon-shaped light guide member 21 was tightly wound about 6.5 times around the outer periphery of the support 6 so that no gap was formed in the adjacent portion, thereby producing the tubular excitation light guide 2. After the both end faces of the excitation light guide 2 are optically polished, one end face is coated with a multilayer film having a reflectance of 99% or more with respect to the excitation light, and the other end face is used as the excitation light introducing member 3. The glass ribbon was connected by heat fusion. The glass ribbon forming the excitation light introducing member 3 is the same as the glass ribbon forming the light guide member 21. However, the production of the excitation light guide 2 and the combination of the excitation light guide 2 and the excitation light source 41 are performed. In order to carry out the bonding efficiently, both were made separately and then fused.

The laser light guide 1 has a core diameter of 50 μm,
A laser fiber having a cladding diameter of 125 μm was used. The core of this laser fiber has a Nd concentration of 0.5 at%.
3+ ions are doped. Quartz glass is used as the base material of the fiber. One end of the fiber has a reflectivity of 98% at a laser oscillation wavelength of 1.06 μm after planar polishing.
A multilayer film coat as described above is applied. Also,
The other end surface is a surface obtained by simply breaking the fiber vertically, and is not coated or the like. The reflectance at the other end is about 4% with respect to the laser oscillation wavelength of 1.06 μm. This laser fiber was wound around the excitation light guide 2 for about 450 turns, about 140 m, to constitute the whole. The refractive index of the excitation light guide 2 is set to be substantially equal to the refractive index of the laser light guide (laser fiber) 1 in the clad portion. As a result, the excitation light transmitted while being totally reflected within the excitation light guide 2 is introduced into the laser light guide 1 without being totally reflected at the contact portion with the laser light guide 1. Will be done. In other words, the excitation light is efficiently introduced from the excitation light guide 2 into the laser light guide 1 by making the refractive indexes of the two at the portions where the excitation light guide 2 and the laser light guide 1 contact each other. A possible optical coupling state is partially formed. Thereby, the pumping light transmitted while being confined in the pumping light guide 2 can be introduced into the laser light guide 1 with high efficiency. In this embodiment, a favorable laser beam 52 output having a laser output of 8 W at a wavelength of 1.06 μm was obtained from the output end (1b) of the laser light guide 1.

When a laser processing apparatus was constructed by providing a condenser lens system (focal length 10 mm) for condensing the output laser light 51 of this fiber type laser apparatus, the diameter was 200 μm.
Within 90% of the output energy could be collected. At this time, the focused diameter of the output laser light was always stable irrespective of the laser output and the state of heat. Although only one ribbon is used in this embodiment, a configuration using a plurality of ribbons may be used as shown in FIG. By doing so, more excitation light can be incident, and high output can be achieved. A light guide member may be further wound on the laser light guide. Further, although the high reflection film is provided on one end face of the ribbon-shaped light guide member, a means for inputting the excitation light from this face may be provided, so that a larger excitation light power is supplied. As a result, high output can be achieved.

(Embodiment 5) In Embodiment 5, FIG.
The laser device was constructed by producing the support 6 shown in FIG. The manufactured support 6 was provided with 12 radiating holes 62 having a diameter of 10 mm in an aluminum cylinder having a diameter of 10 cm, whereby the surface area was increased by about 30% and the radiating effect could be greatly increased. With the enhancement of the heat radiation effect, the strength and stability of the excitation light guide 2 could be improved.

(Embodiment 6) In Embodiment 6, a laser device having a circulation reproduction type light guide structure shown in FIG. 10 was constructed. In this laser device, the ribbon-shaped light guide member 21 was spirally wound to form a substantially tubular excitation light guide 2. The excitation light 51 is introduced from one end 21a of the light guide member 21, and the excitation light reaching the other end 21b is re-introduced to the one end 1a and circulated. Between the other end 21b and one end 21a of the light guide member 21, a return light guide member 32 was provided. The excitation light guide 2 has an outer diameter of 10 cm,
An aluminum cylinder having an inner diameter of 9 cm and a length of 7 cm is used as a support 6, and the outer periphery of the support 6 is uniformly coated with a resin having a refractive index of about 1.38. 21 was produced by winding it about three times so that no gap was formed. Ribbon-shaped light guide member 21
Was constructed by winding the same fibrous laser light guide 1 as in the previous embodiment for about 150 turns, approximately 45 m, on the excitation light guide 2 produced by stretching quartz glass by drawing. The excitation light source 41 used was the same as in the previous embodiment. As the return light-guiding member 32, a tapered ribbon having a width narrowing from 10 mm to 5 mm was used. The material is the excitation light guide 2
The same quartz glass as that of the excitation light guiding member 21 forming the above was used, the thickness was 250 μm, and the length was about 1 m. One end 21a of the excitation light guide member 21 is provided with the return light guide member 32.
Is connected to the end (32a) on the 10 mm width side. Also,
The other end 21b of the light guide member 21 is connected to the 5 mm width side end (32b) of the return light guide member 32. As a result, the excitation light could be re-introduced from the other end 21b of the light guide member 21 to the one end 21a with an efficiency of 95% or more. One end 21a of the excitation light guide member 21 has an excitation light source 4
The other end 3b of the ribbon-shaped excitation light introducing member 3 is also connected to introduce the excitation light 51 from 1; The width is tapered from 10 mm to 5 mm from one end 3a to the other end 3b. One end 21a of the excitation light guide member 21 is divided into two portions each having a width of 5 mm, and the excitation light 51 from the excitation light source 41 is newly introduced at one division width of 5 mm, and the excitation light is divided at the other division width of 5 mm. To reintroduce.

According to the configuration of this embodiment, the pumping light 51 once introduced into the pumping light guide 2 keeps going around the pumping light guide 2 until it is absorbed by the laser light guide 1. All will be used effectively for laser excitation. With the light guide structure as described above, the laser light guide 1
Can be shortened. In other words, the pump light that has not been absorbed is repeatedly re-introduced into the pump light guide 2 and circulates. Can be secured. Thereby, the design of the excitation light guide 2 is facilitated, and high excitation efficiency can be obtained even if the size of the excitation light guide 2 is reduced. Further, it is not necessary to set the length of the laser light guide 1 so that the excitation light is absorbed before exiting from the excitation light guide 2, and the loss of the excitation light can be suppressed even if the length is shortened. Now you can. Thereby, a high-efficiency or high-output laser height can be obtained even if the laser light guide 1 is shortened. Further, since the amount of the expensive laser light guide 1 to be used can be reduced, the advantage of cost reduction can be obtained. further,
One end 21a of the excitation light guide member 21 serving as an entrance of the excitation light
Is closed by the other end 3b of the excitation light introducing member 3 which is the exit of the excitation light from the excitation light source 41 and the other end 32b of the return light guiding member 32 which is the exit of the excitation light to be re-introduced. Therefore, leakage of the excitation light from the entrance can be almost eliminated. According to the above operation, in this embodiment, the wavelength 1.06 μm
As a result, a good output laser beam 52 of 10 W was obtained at m.

(Embodiment 7) In Embodiment 7, a laser device having the structure shown in FIG. 8 was constructed. In this embodiment, first,
The same ribbon-shaped excitation light-guiding member 21 and fiber-shaped laser light-guiding member 1 as in the above-described embodiment were used. As the support 6, an aluminum cylinder as shown in FIG. 7 was used. A guide groove 63 having a depth of 550 μm is formed on the support 6, and a gold plating 64 is applied to the surface of the groove 63. Inside the groove 63, as in the previous embodiment,
A resin having a refractive index of about 1.38, almost the same as quartz glass, was uniformly coated. After winding the ribbon-shaped excitation light guide member 21 and the fiber-shaped laser light guide 1 in the groove 63, a resin having a refractive index of about 1.46 was applied so as to embed the laser light guide 1. Further, the groove 63 was covered with a cover member 65 provided with gold plating 64.

In the laser device of this embodiment, since the refractive index of the resin covering the laser light guide 1 is substantially the same as that of quartz glass, the excitation light propagating in the excitation light guide member 21 has a high probability. Can be moved to the resin side. Further, the optical contact area between the excitation light guide member 21 and the laser light guide 1 can be increased by the resin. As a result, the excitation light is efficiently absorbed by the laser active substance in the core portion through the clad portion of the laser light guide (laser fiber) 1. Also, of the excitation light propagating in the excitation light guide member 21, the light that has broken total reflection and leaked out of the light guide member 21 is also subjected to gold plating 6.
Since the light is reflected by the reflection surface of No. 4 and can reach the laser light guide 1 again, the excitation light can be used efficiently. As a result, in this example, a favorable output laser beam 52 having a wavelength of 1.06 μm and a laser output of 13 W could be obtained from the output end (1b) of the laser light guide 1.

Example 8 In Example 8, a laser device having the structure shown in FIG. 16 was formed. In this embodiment, a sheet-like light guide member 21 for forming the excitation light guide 2 is
It was produced by drawing quartz glass. The produced sheet-shaped light guide member 21 has a width of 60 mm, a thickness of 250 μm, and a length of 3.
It was a 14 mm glass sheet, and both ends were optically polished. The sheet-shaped light guide member 21 has an outer diameter of 10c.
m, on an aluminum cylindrical support 6 having an inner diameter of 9 cm,
Winding was performed at an angle of about 1.82 degrees with respect to the circumferential direction, and the both end faces were fusion-spliced to produce a substantially tubular excitation light guide 2. The support 6 has a surface plated with gold, and a thin coating of a resin having a refractive index of about 1.38 on the surface. The manufactured tubular excitation light guide 2 tilts the light guide member 21 slightly in the axial direction. As a result, the shape is formed into a shape having an abutting surface 21c where both end surfaces are in contact with each other and offset surfaces (non-abutting surfaces) 211a and 211b where both end surfaces are not in contact with each other. Offset surfaces 211a, 2
11b each form an excitation light incident surface having a width of 10 mm. This plane of incidence is oriented substantially circumferentially.

Each of the offset surfaces 211 a and 211 b is connected to the excitation light source 41 via a bundle of optical fibers 31 forming the excitation light introducing member 3. Each excitation light source 41
Are LDs each having 21 LD elements arranged in a line.
It is configured using four element arrays. As a whole, 168 LD elements are used (21 elements × 4 × 2). 84 optical fibers 3 are provided between the offset surfaces 211a and 211b and the excitation light sources 41 and 41, respectively.
1 was used. This optical fiber 31 is made of quartz,
It is an air clad type without a clad part. In this case, one optical fiber 31 is used to guide light emission of one LD element. So, overall,
168 optical fibers 3 corresponding to 168 LD elements
1 is used as the excitation light introducing member 3. The 168 optical fibers 31 are divided into two groups of 68 and used.
One optical fiber 31 group is provided with one offset surface 211a.
And the pumping light source 41, and the other optical fiber 31 group connects between the other offset surface 211b and the pumping light source 41. One end surface of each optical fiber 31 is directly opposed to the light emitting surface of each LD element by the positioning jig 7. The other end surfaces of the optical fibers 31 are connected to the offset surfaces 211a and 211b by fusion. Although the positioning jig 7 is not shown in the drawings, 9
A guide groove having a V-shaped cross section of 0 degree is machined at a pitch of 500 μm, and an optical fiber 31 is formed in the guide groove.
Position and hold one end of the. The positioning jig 7 is divided into units corresponding to each LD array. Each unit has the number of elements (2
21), and the 21 optical fibers 31 are positioned and held.

A laser device was constructed by winding the laser light guide (laser fiber) 1 around the excitation light guide 2 for 400 turns and about 125 m. Laser light guide 1 according to the first embodiment
A laser fiber having a core diameter of 50 μm and a clad diameter of 125 μm was used in the same manner as described above. The core of the laser fiber is doped with Nd3 + ions at a concentration of 0.5 at%. The base material of the laser fiber is quartz glass, and its one end 1a surface is polished to a flat surface, and has a laser oscillation wavelength of 1.06.
A multilayer coating is applied so that the reflectance at 98 μm is 98% or more. The other end 1b surface is only a surface obtained by vertically breaking the fiber, and is not coated.
The reflectivity at the surface 1b of the other end is a laser oscillation wavelength of 1.06.
It is about 4% with respect to μm. The light output of each LD element is 2 W, and the connection from the pump light source 41 to the pump light guide 2 can be connected at an efficiency of about 90%, so that about 300 W of pump light is supplied to the pump light guide 2. Could be introduced. Then, a favorable output laser beam 52 having a wavelength of 1.06 μm and a laser output of 110 W was obtained from the output end of the laser fiber. Further, the excitation light guide 2 used in the fiber laser device of this embodiment has a simple configuration in which the sheet-shaped light guide member 21 is simply wound around once, so that its manufacture is easy.

In this embodiment, the light guide member 21 whose plane shape is a rectangular sheet is inclined and wound around a cylinder. However, the conductive member 21 is formed into a parallelogram by cutting and polishing the both end surfaces obliquely. It may be processed. In this embodiment, the excitation light guide 2 is manufactured by winding the sheet-like light guide member 21 so that a part of both end surfaces thereof remains as the offset surfaces 211a and 211b. The configuration may be such that only one side appears, or the offset surface does not appear on both sides. When the end surfaces of the sheet-shaped conductive member 21 are completely overlapped with each other so that the offset surfaces 211a and 211b do not occur, for example, as shown in FIG. And the tapered cut surface 3c is used as the sheet-like conductive member 21.
May be configured to be fusion-spliced along the side surface of the sheet. Also in this configuration, the excitation light can be introduced into the excitation light guide 2.

(Embodiment 9) This embodiment is an example in which the light guide member 21 is heated and wound just before the light guide member 21 is wound around the support 6 in substantially the same manner as in the first embodiment. FIG. 21 is an explanatory diagram of the laser device manufacturing method according to the ninth embodiment. As shown in FIG. 21, in this embodiment, the difference from the first embodiment is before the ribbon-shaped light guide member 21 is wound around the support 6 and before the laser light 81 is irradiated, 21 is guided between the lower guide member 9a and the upper guide member 9b so as to be sandwiched between the lower guide member 9a and the upper guide member 9b. 6 is separated from the surface 6 by a sufficient distance. In this embodiment, the distance is set to about 10 mm. Further, in this case, the laser light irradiating section 8 is formed so that the light guide member 21 can be wrapped around the support 6 satisfactorily while maintaining the laser light irradiating section 810 at a sufficient distance from the surface of the support 6.
In a portion ahead of 10, by the guide roller 9c,
The heated light guide member 21 is pressed against the support 6. In this embodiment, the distance between the position of the laser beam irradiating section 810 and the position where the light guide member 21 starts contacting the support 6 is about 30 mm. In this embodiment, in addition to the above points, the outer diameter is 10 cm, the inner diameter is 9 cm, and the length (cylinder length) is 7 cm.
The other configuration was the same as that of Example 1 except that a support having a size of cm was used and that the output of the CO2 laser was set to 340 W.

According to the ninth embodiment, the glass ribbon-shaped light guide member 21 does not break during winding or the like, nor does it come loose after winding, and maintains a stable shape. Was. In the above embodiment, the distance between the laser beam irradiating section 810 of the light guide 21 and the support 6 is set to 10
However, the distance may be any distance that can prevent heat from escaping from the light guide 21 to the support 6, and may be usually several mm or more. In addition, the method of this embodiment can of course be applied to the case where the light guide member is in a sheet shape other than the ribbon shape or the like, or the case where the winding or folding of the laser light guide is performed while heating.

FIGS. 22 and 23 are diagrams for explaining the effects of the ninth embodiment. For comparison with the ninth embodiment, FIG.
As shown in FIG. 2, the laser beam irradiation unit 810 is
Consider a case where the wire is wound while being brought into direct contact with. In this case, since the heat escapes on the side of the light guide member 21 that is in contact with the support 6, the temperature does not rise sufficiently, and the stress release becomes insufficient. FIG. 23B shows this state. In the figure, the length of the arrow indicates the amount of deformation. The outer stretch is eliminated, but the inner stretch remains compressed.
In addition, the surface temperature increases due to a steep internal temperature gradient, which may cause evaporation of the glass. It is assumed that after the support 6 has been wound, the winding force is loosened or removed from the support 6. In that case, as the diameter increases, the internal deformation is
As shown in (c), the inner and outer peripheries are both compressed. Therefore, strength against bending is reduced. In addition, the deformation may cause the wound state to be loosened and separated. In the case where the heat treatment itself is not performed, as shown in FIG. 23 (a), the inside is compressed and the outside is stretched by winding, so that the winding force is loosened after winding, When detached from the support 6, this force acts, and there is a high possibility that the support 6 is separated.

On the other hand, in the case of the ninth embodiment, such a problem is solved. That is, since the heated portion can be regarded as substantially insulated, the temperature gradient in the thickness direction of the light guide member 21 becomes gentle. Therefore, it is possible to heat up to the back surface without excessively increasing the surface temperature. Further, at this time, the distance between the laser beam heating unit and the support can be appropriately set by the guide member, the guide roller, and the like, so that the effect can be ensured.

As described above, according to the first aspect of the present invention, the pumping light guide that propagates the pumping light while confining the pumping light, and the pumping light is distributed and introduced from the pumping light guide including the laser active material. And a long and flexible laser light guide that excites the laser active substance and outputs a laser beam, thereby producing a thin, flexible plate. A step of forming an excitation light guide having a predetermined shape by winding the light guide member while imparting and maintaining the shape of the light guide member with a support; and a predetermined length range of the laser light guide relative to the excitation light guide. Winding or folding the laser light guide before or after the excitation light guide is formed so as to make an optical contact directly or indirectly through an optical medium that transmits the excitation light. And have By these steps, a method of manufacturing a laser device, which comprises forming excited structure to distribute guide the excitation light from the excitation light light guide to said laser beam guide body. This makes it possible to relatively easily and inexpensively form a pumping light guide having a light guiding structure capable of distributing and introducing the pumping light to the laser light guide while efficiently confining the pumping light with a small transmission loss of the pumping light. Can be. Therefore, the advantages of the method of distributing and introducing excitation light into a laser light guide having a long structure such as a laser fiber, for example, the advantages of a fiber laser having excellent light-collecting properties and thermally stable output and transverse modes are obtained. It is possible to provide a low-cost laser device that can maintain a high utilization efficiency of the excitation light and can output a high output or a high efficiency laser light.

According to a second aspect of the present invention, in the first aspect, the laser light guide is wound or folded along the surface of the excitation light guide formed on the support, thereby forming the laser light guide. A method of manufacturing a laser device, wherein a predetermined length range optically contacts the excitation light guide to form an excitation structure in which excitation light is distributed and introduced. Thus, the pumping light can be efficiently introduced from the outer surface of the pumping light guide into the laser light guide, and a high-efficiency or high-power laser device can be configured at low cost.

According to a third aspect of the present invention, in the first or second aspect, the excitation light guide is wound on a support on which the laser light guide is wound in advance, so that the laser light guide has a predetermined shape. A method for manufacturing a laser device, characterized in that a length range optically contacts the excitation light guide to form an excitation structure in which excitation light is distributed and introduced. This allows
By efficiently introducing the excitation light into the laser light guide from the inner surface of the excitation light guide, a high-efficiency or high-power laser device can be configured at low cost. Can be.

According to a fourth aspect of the present invention, in any one of the first to third aspects, the shape imparting of the light guide member in the step of forming the excitation light guide and / or the winding or turning of the laser light guide are performed. This is a method for manufacturing a laser device that is performed while heating. This allows the light guide member to be wound around the support without breaking the light guide member.
In addition, the excitation light guide can be formed stably and smoothly without causing shape instability due to springback or the like, and an excitation light guide having optically stable performance can be formed.

A fifth invention is a method for manufacturing a laser device according to any one of the first to fourth inventions, wherein the excitation light guide formed into a predetermined shape by winding is annealed. This makes it possible to obtain an excitation light guide capable of exhibiting optical uniform, stable and good light guide characteristics by removing internal strain of the light guide member.

According to a sixth aspect of the present invention, in any one of the first to fifth aspects, the excitation light guide is formed by using a ribbon-shaped light guide having two main surfaces, a front surface and a back surface. A method for manufacturing a laser device, wherein a laser light guide is brought into optical contact with either one of the two main surfaces directly or via an optical medium transmitting excitation light. Accordingly, an excitation light guide having a hollow thin-walled structure such as a tubular or cylindrical shape can be obtained at low cost.

According to a seventh aspect of the present invention, in any one of the first to sixth aspects, a fiber having a core portion containing a laser active substance and a clad portion surrounding the core portion and providing a predetermined waveguide structure. This is a method for manufacturing a laser device using a laser light guide in a shape of a circle. This makes it possible to configure a laser device that utilizes the advantages of a fiber laser, for example, having excellent light-collecting properties and thermally stable output and transverse mode.

According to an eighth aspect of the present invention, an excitation light guide is formed by winding a light guide member in a groove formed in advance on a support, and the excitation light guide and the excitation light from the excitation light guide are formed. The laser light guide of the portion receiving the distribution introduction is housed in the groove, and the structure is formed such that the excitation light leaking from the excitation light guide is confined in the groove and distributed and introduced into the laser light guide. A method for manufacturing a laser device. Thereby, workability and reproducibility when winding the light guide member 21 can be improved. Further, by forming a structure for confining the light leaking from the excitation light guide into the groove, the efficiency of introducing the excitation light into the laser light guide can be increased.

A ninth aspect of the present invention is an excitation light guide for confining and propagating excitation light, and a laser active substance containing a laser active substance, and the excitation light being distributed and introduced from the excitation light guide to excite the laser active substance. A method for manufacturing an optical amplifier having a long and flexible laser light guide for performing optical amplification by performing a light guide member having a thin and flexible shape with a support. A step of forming an excitation light guide having a predetermined shape by winding while maintaining the shape; and an optical medium in which a predetermined length range of the laser light guide is directly or through the excitation light with respect to the excitation light guide. Winding or folding the laser light guide before or after the excitation light guide is formed, so as to form an optical contact state indirectly through,
A method of manufacturing an optical amplifier, comprising forming an excitation structure for distributing and guiding excitation light from the excitation light guide to the laser light guide. As a result, the advantages of a system in which the excitation light is distributed and introduced into a laser light guide having a long structure such as a laser fiber, for example, the advantages of a fiber laser having excellent condensing properties and thermally stable output and transverse modes are obtained. It is possible to provide a low-cost laser device that has high utilization efficiency of pump light and can perform high-output or high-efficiency optical amplification while maintaining the same.

[0099]

As is apparent from the above description, the present invention provides an excitation light guide having a predetermined shape by winding a thin plate-shaped flexible light guide member while shaping and holding the shape with a support. Forming a light body, and winding or folding a predetermined length range of the long laser light guide along the surface of the support or the excitation light guide, thereby providing a predetermined length of the laser light guide. The range is characterized by forming an excitation structure in which the excitation light is distributed and introduced by optically contacting the excitation light guide, whereby the utilization efficiency of the excitation light is high, high output or A highly efficient laser device and optical amplifier can be provided at low cost.

[Brief description of the drawings]

FIG. 1 is a schematic perspective view schematically showing one embodiment of a main part of a method for manufacturing a laser device according to the present invention.

FIG. 2 is a view schematically showing one embodiment of a light guide member used in the method shown in FIG.

FIG. 3 is a perspective view schematically showing one embodiment of an excitation light guide formed by the method shown in FIG. 1;

FIG. 4 is a perspective view and a partial cross-sectional view schematically showing one embodiment of a laser device configured by the method shown in FIG.

FIG. 5 is a perspective view schematically showing another embodiment of the excitation light guide 2 manufactured according to the present invention.

FIG. 6 is a schematic perspective view showing a configuration example of a support used in the present invention.

FIG. 7 is a schematic perspective view showing another configuration example of the support used in the present invention.

FIG. 8 is a cross-sectional view schematically showing a second embodiment of the laser device configured according to the present invention.

FIG. 9 is a schematic perspective view schematically showing a third embodiment of the laser device constituted by the present invention.

FIG. 10 is a schematic perspective view schematically showing a laser device according to a fourth embodiment of the present invention.

FIG. 11 is a perspective view schematically showing still another embodiment of the excitation light guide.

FIG. 12 is a cross-sectional view schematically illustrating a configuration example of a sheet-shaped light guide member.

13 is a perspective view and a development view schematically showing an application example of the excitation light guide shown in FIG.

FIG. 14 is a developed view schematically showing another example of the light guide structure formed by using the excitation light guide shown in FIG.

FIG. 15 is a perspective view schematically showing a fifth embodiment of the laser device constituted by the present invention.

FIG. 16 is a perspective view schematically showing a sixth embodiment of the laser device constituted by the present invention.

FIG. 17 is a partially cutaway perspective view schematically showing a seventh embodiment of the laser device constituted by the present invention.

FIG. 18 is a sectional view showing another embodiment of the method for manufacturing a laser device according to the present invention.

FIG. 19 is an enlarged sectional view showing a first embodiment of an optical contact state between a laser light guide and an excitation light guide.

FIG. 20 is an enlarged sectional view showing a second embodiment of an optical contact state between a laser light guide and an excitation light guide.

FIG. 21 is an explanatory diagram of the method of manufacturing the laser device according to the ninth embodiment.

FIG. 22 is a diagram for explaining an effect of the ninth embodiment.

FIG. 23 is a view for explaining effects of the ninth embodiment.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Laser light guide 11 Core part 12 Cladding part 1a One end of laser light guide 1 1b The other end of laser light guide 1 2 Excitation light guide 21 Excitation light guide 21a One end of light guide 21 21b Light guide 21 21c Butt surface 210 Light guide member 211a Offset surface 211b Offset surface 22 Resin 23 Optical medium 3 Excitation light introduction member 3a One end of excitation light introduction member 3 3b The other end of excitation light introduction member 3 3c Taper cut surface 32 Return Light guide member 32a One end of the light guide member for return 32b The other end of the light guide member for return 41 Excitation light source 42 Condensing optical system 51 Excitation light 52 Laser light 6 Support body 61 Hollow portion 62 Heat radiating hole 63 Guide groove 64 Reflecting surface Plating layer 65 for forming cover 65 Cover member 7 Positioning jig 81 Laser light beam 82 Laser light source 83 Beam span 84 mirror 85 the cylindrical lens 86 mask plate

Claims (9)

[Claims] 1. An excitation light guide for confining and propagating excitation light, and a laser light containing a laser active material, wherein the excitation light is distributed and introduced from the excitation light light guide to excite the laser active material to produce a laser light. A method for manufacturing a laser device, comprising: a long and flexible laser light guide that outputs light, wherein a thin plate-shaped flexible light guide member is shaped and retained by a support. A step of forming an excitation light guide having a predetermined shape by being wound, and a predetermined length range of the laser light guide with respect to the excitation light guide, directly or via an optical medium that transmits excitation light. Winding or folding the laser light guide before or after the excitation light guide is formed so as to form an indirect optical contact state, Above body A method for manufacturing a laser device, comprising forming an excitation structure for distributing and guiding excitation light to the laser light guide. 2. A laser light guide is wound or folded along a surface of an excitation light guide formed on a support, so that a predetermined length range of the laser light guide is set to the excitation light guide. 2. The method according to claim 1, further comprising forming an excitation structure in which the excitation light is distributed and introduced by optically contacting the laser beam. 3. An excitation light guide is wound on a support on which a laser light guide is previously wound, so that a predetermined length range of the laser light guide is optically controlled by the excitation light guide. 3. The method for manufacturing a laser device according to claim 1, wherein an excitation structure is formed in which excitation light is distributed and introduced upon contact. 4. The method according to claim 1, wherein the shaping of the light guide member and / or the winding or folding of the laser light guide in the step of forming the excitation light guide are performed while heating. 3. The method for manufacturing a laser device according to claim 1. 5. The method for manufacturing a laser device according to claim 1, wherein an annealing process is performed on the excitation light guide formed into a predetermined shape by winding. 6. An excitation light guide is formed by using a ribbon-shaped light guide member having two main surfaces, a front surface and a back surface, and either one of the two main surfaces is directly or excitation light. The method for manufacturing a laser device according to claim 1, wherein the laser light guide is brought into optical contact with an optical medium through an optical medium that transmits light. 7. A fiber laser light guide having a core containing a laser active substance and a clad surrounding the core to provide a predetermined waveguide structure. A method for manufacturing the laser device according to any one of the above. 8. An excitation light guide is formed by winding a light guide member in a groove previously formed in a support, and distribution of excitation light is introduced from the excitation light guide and the excitation light guide. The laser light guide of the receiving part is housed in the groove, and a structure is formed in which the excitation light leaking from the excitation light guide is confined in the groove and distributed and introduced into the laser light guide. The method for manufacturing a laser device according to claim 1. 9. An excitation light guide for confining and propagating excitation light, and a laser active material containing a laser active material and being excited by distribution of the excitation light from the excitation light guide. A method of manufacturing an optical amplifier having a long and flexible laser light guide for performing optical amplification, wherein a thin plate-shaped flexible light guide member is shaped and held by a support. A step of forming an excitation light guide of a predetermined shape by winding, and a predetermined length range of the laser light guide relative to the excitation light guide, directly or indirectly through an optical medium transmitting the excitation light. Winding or turning the laser light guide before or after the excitation light guide is formed so as to form an optically-contact state in an optical manner, and the excitation light guide is From above A method for manufacturing an optical amplifier, comprising: forming an excitation structure that distributes and guides excitation light to the light guide.