JP6579569B2 - Solid state laser element - Google Patents

Description

  The present invention relates to a solid-state laser element.

  Conventionally, laser oscillators using optical fibers, so-called fiber lasers, have been widely used. This laser oscillator oscillates laser light by an optical fiber using excitation light.

  Since the fiber laser has a thin core, there is a problem that if the pulse laser having a large output is oscillated, the core is damaged. For this reason, when the pulse laser is oscillated, it is preferable to use a disk-shaped or rod-shaped laser medium as described in Patent Document 1.

JP 2008-177226 A

  In order to obtain high output light, the disk-shaped or rod-shaped laser medium is preferably large. However, when the size of the laser medium is increased, there is a problem that it is difficult to sufficiently dissipate heat inside the solid-state laser element.

  An object of the present invention is to provide a solid-state laser element capable of sufficiently dissipating heat inside.

  A solid-state laser element according to an aspect of the present invention includes a plurality of laser media and at least one heat radiating member. Each laser medium is formed of fluoride glass doped with a laser active material. Each laser medium is rod-shaped or plate-shaped. The heat dissipation member has a higher thermal conductivity than each laser medium. The heat dissipating member is disposed between the laser media.

  According to this configuration, since the heat dissipating member is disposed between the laser media, the heat of each laser medium can be dissipated through the heat dissipating member. For this reason, the inside of the solid-state laser element can be sufficiently radiated. In addition, by providing a plurality of laser media, the solid-state laser element can emit high-power output light.

  Preferably, the solid-state laser element further includes first and second cover members. The first cover member is disposed so as to cover the end surface of the laser medium located at one end of the plurality of laser media. The second cover member is disposed so as to cover the end surface of the laser medium located at the other end of the plurality of laser media.

  Preferably, the first and second cover members have higher thermal conductivity than the laser medium. According to this configuration, by radiating heat through the first and second cover members, it is possible to prevent the laser medium located at the end from being damaged by heat.

  Preferably, the first and second cover members do not have deliquescence. According to this configuration, even when the laser medium has deliquescent properties, the end surfaces of the laser medium disposed at the end portions are covered with the first and second cover members. Can be prevented.

  Preferably, the transmission wavelength range of each of the first and second cover members includes the transmission wavelength range of the laser medium. According to this configuration, according to this configuration, it is possible to prevent the transmission of light such as output light and excitation light transmitted through the laser medium from being hindered by the first and second cover members.

  Preferably, each laser medium and each heat radiating member are bonded to each other.

  Preferably, each laser medium and each said heat radiating member are welded together. According to this configuration, each laser medium and each heat dissipation member can be sufficiently bonded to each other.

  The transmission wavelength range of each heat radiating member includes the transmission wavelength range of the laser medium. According to this configuration, it is possible to prevent transmission of light such as output light and excitation light that is transmitted through the laser medium from being hindered by each heat radiating member.

  Preferably, each laser medium and each heat radiating member have mutually different main components.

  Preferably, the laser medium is formed of ZBLAN (Zr, Ba, La, Al, Na) glass or HBLAN (Hf, Ba, La, Al, Na) glass.

  Preferably, the heat radiating member is formed of calcium fluoride or magnesium fluoride.

  The solid-state laser element according to the present invention can sufficiently dissipate the inside.

The side view of a solid-state laser element. The figure which shows the manufacturing method of a solid-state laser element. The schematic diagram which shows the structure of the laser oscillator which uses a solid state laser element. The side view of the solid-state laser element which concerns on the modification 1. FIG. The side view of the solid-state laser element which concerns on the modification 2. FIG. The side view of the solid-state laser element which concerns on the modification 3. FIG. The side view of the solid-state laser element which concerns on the modification 4. FIG. FIG. 10 is a schematic diagram illustrating a configuration of a laser oscillator according to a fifth modification.

  Hereinafter, embodiments of a solid-state laser element according to the present invention will be described with reference to the drawings. FIG. 1 is a side view of a solid-state laser element. As shown in FIG. 1, the solid-state laser element 10 includes a plurality of laser media 1, a plurality of heat radiating members 2, a first cover member 3, and a second cover member 4.

  Each laser medium 1 has a plate shape. Specifically, each laser medium 1 has a disk shape. Each laser medium 1 may have a rectangular cross section. Each laser medium 1 has an axial length shorter than a diameter. The axial direction is the left-right direction in FIG.

  Each laser medium 1 is made of fluoride glass. Specifically, each laser medium 1 is made of zirconium fluoride glass. More specifically, each laser medium 1 is made of ZBLAN (Zr, Ba, La, Al, Na) glass or HBLAN (Hf, Ba, La, Al, Na) glass. Each laser medium 1 has deliquescence.

  Each laser medium 1 is doped with a rare earth ion such as erbium, thulium, or holmium as a laser active material. Other laser active materials include neodymium, praseodymium, ytterbium, and dysprosium.

  Each heat radiating member 2 has substantially the same size as each laser medium 1 when viewed in the axial direction. Each heat radiating member 2 has a disk shape. The diameter of each heat radiating member 2 is preferably the same as the diameter of each laser medium 1. When each laser medium 1 is rectangular when viewed in the axial direction, each heat radiating member 2 is also preferably rectangular when viewed from the axial direction following each laser medium 1.

  Each heat radiating member 2 has higher thermal conductivity than each laser medium 1. Each heat radiating member 2 does not have deliquescence. Each heat radiating member 2 has optical transparency. Specifically, each heat radiating member 2 transmits excitation light and output light.

  The wavelength range of each heat radiating member 2 includes the wavelength of output light from each laser medium 1. For example, the transmission wavelength range of each heat radiating member 2 preferably includes the transmission wavelength range of each laser medium 1. For example, the transmission wavelength region of each heat radiating member 2 can be about 0.2 μm or more and 7 μm or less. In addition, each heat radiating member 2 can be formed with calcium fluoride or magnesium fluoride.

  Each heat radiating member 2 is different in main component from each laser medium 1. That is, each heat radiating member 2 is made of a crystal material, and each laser medium 1 is made of a glass material.

  Since the 1st and 2nd cover members 3 and 4 are the structures similar to the heat radiating member 2 except that arrangement | positioning differs from the heat radiating member 2 mentioned above, detailed description is abbreviate | omitted.

  Each heat radiating member 2 is disposed between the laser media 1 in the axial direction. That is, the heat radiating member 2 is disposed between two adjacent laser media 1. In the present embodiment, the laser media 1 and the heat radiating members 2 are alternately arranged in the axial direction.

  Each heat radiating member 2 is bonded to each laser medium 1. That is, each heat radiating member 2 is bonded to each adjacent laser medium 1. Specifically, each heat radiating member 2 is fused to each adjacent laser medium 1.

  The first cover member 3 is disposed so as to cover the end surface of the laser medium 1 located at one end of the plurality of laser media 1. In this embodiment, the 1st cover member 3 is arrange | positioned so that the end surface of the laser medium 1 located in the left end part of FIG. 1 may be covered. The first cover member 3 is bonded to the laser medium 1 located at this end. Specifically, the first cover member 3 is welded to the laser medium 1.

  The 2nd cover member 4 is arrange | positioned so that the end surface of the laser medium 1 located in the other edge part among the several laser media 1 may be covered. In this embodiment, the 2nd cover member 4 is arrange | positioned so that the end surface of the laser medium 1 located in the right end part of FIG. 1 may be covered. The second cover member 4 is bonded to the laser medium 1 located at this end. Specifically, the second cover member 4 is welded to the laser medium 1.

  Next, a method for manufacturing the solid-state laser element 10 will be described. As shown in FIG. 2, first, each laser medium 1, each heat radiating member 2, and the first and second cover members 3 and 4 are laminated. And by heating the side surface of this laminated body with the heater 100, each member which comprises a laminated body is mutually fuse | fused. Specifically, each laser medium 1 is melted and fused to each heat radiating member 2 and first and second cover members 3 and 4. In addition, the heater 100 may be arrange | positioned so that the side surface of a laminated body may be surrounded so that the whole side surface of a laminated body may be heated. The heating temperature at this time is preferably about the glass transition temperature of the laser medium 1 or less than the crystallization start temperature of the laser medium 1.

  Next, a laser oscillator using the solid state laser element 10 will be described. As shown in FIG. 3, the laser oscillator 60 includes the solid-state laser element 10 described above. The laser oscillator 60 further includes a seed light source 61 and an excitation light source 62. The excitation light source 62 outputs excitation light, and the seed light source 61 outputs seed light.

  The seed light 103 output from the seed light source 61 and the excitation light 104 output from the excitation light source 62 are guided to the solid-state laser element 10 from the first cover member 3 side. For example, the combiner 101 is arranged at a distance from the first cover member 3. The combiner 101 transmits the seed light 103 and reflects the excitation light 104 to the first cover member 3.

  The seed light 103 incident on the solid-state laser element 10 is amplified in the solid-state laser element 10 and is emitted as output light 105 from the second cover member 4 side. A splitter 102 is disposed at a distance from the second cover member 4. The output light 105 emitted from the solid-state laser element 10 passes through the splitter 102, while the excitation light 104 emitted from the solid-state laser element 10 is reflected by the splitter 102. Thereby, the excitation light 104 and the output light 105 are separated.

  According to the solid-state laser element 10 according to the present embodiment, since each heat radiating member 2 is disposed between each laser medium 1, the heat of each laser medium 1 can be radiated through each heat radiating member 2. . For this reason, the inside of the solid-state laser element 10 can be sufficiently radiated. In addition, by providing the plurality of laser media 1, the solid-state laser element 10 can emit high-power output light.

[Modification]
As mentioned above, although embodiment of this invention was described, this invention is not limited to these, A various change is possible unless it deviates from the meaning of this invention.

Modification 1
As shown in FIG. 4, each laser medium 1 may have a rod shape. Specifically, each laser medium 1 may be cylindrical. That is, each laser medium 1 may have an axial length longer than a diameter.

Modification 2
As shown in FIG. 5, each laser medium 1 may be a mixture of a rod-shaped laser medium 1 and a plate-shaped laser medium 1.

Modification 3
As shown in FIG. 6, the heat radiating member 2 may be continuously arranged. Similarly, a part of the laser medium 1 may be continuously arranged.

Modification 4
As shown in FIG. 7, the solid-state laser element 10 may further include a heat sink 5. The heat sink 5 is in contact with the side surface of each laser medium 1. Preferably, the heat sink 5 is in contact with each heat radiating member 2 and the first and second cover members 3 and 4. The heat sink 5 has a heat sink body 51 formed of a material having higher thermal conductivity than each laser medium 1. In addition, the heat sink 5 has a pipe 52 that passes through the inside of the heat sink body 51, and a coolant such as water can flow through the pipe 52.

Modification 5
The laser oscillator 60 using the solid-state laser element 10 may be configured to output laser light using an excitation light source and a resonator. Specifically, as shown in FIG. 8, the laser oscillator 60 includes the solid-state laser element 10, an excitation light source 62, and a resonator 63.

  The resonator 63 includes a rear mirror 63a and an output mirror 63b. The rear mirror 63 a is disposed on the first cover member 3 side of the solid-state laser element 10. The output mirror 63b is disposed on the second cover member 4 side.

  The excitation light 104 output from the excitation light source 62 is incident on the solid-state laser element 10 through the rear mirror 63a. The output light emitted from the solid-state laser element 10 is emitted through the output mirror 63b.

DESCRIPTION OF SYMBOLS 1 Laser medium 2 Heat radiation member 3 1st cover member 4 2nd cover member 10 Solid state laser element

Claims (10)

A plurality of rod-shaped or plate-shaped laser media formed of fluoride glass doped with a laser active material;
At least one heat radiating member having a higher thermal conductivity than each of the laser media and disposed between the laser media;
A heat sink in contact with the plurality of laser media and the heat dissipation member;
Equipped with a,
The solid-state laser element , wherein each laser medium and each heat dissipation member are bonded to each other . A first cover member disposed to cover an end surface of the laser medium located at one end of the plurality of laser media;
A second cover member arranged to cover an end face of the laser medium located at the other end of the plurality of laser media;
Further comprising
The heat sink is in contact with the first and second cover members;
The solid-state laser device according to claim 1. The first and second cover members have higher thermal conductivity than the laser medium;
The solid-state laser device according to claim 2. The first and second cover members have no deliquescence,
The solid-state laser device according to claim 2 or 3. The transmission wavelength range of each of the first and second cover members includes the transmission wavelength range of the laser medium.
The solid-state laser element according to claim 2. Each laser medium and each heat dissipation member are welded to each other.
Solid-state laser device according to any of claims 1 to 5. The transmission wavelength range of each of the heat dissipation members includes the transmission wavelength range of the laser medium.
Solid-state laser device according to any of claims 1 to 6. Each laser medium and each heat dissipation member have different main components from each other.
Solid-state laser device according to any of claims 1 to 7. The laser medium is formed of ZBLAN (Zr, Ba, La, Al, Na) glass or HBLAN (Hf, Ba, La, Al, Na) glass.
Solid-state laser device according to any one of claims 1 to 8. The heat dissipation member is formed of calcium fluoride or magnesium fluoride.
Solid-state laser device according to any of claims 1 to 9.

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