Laser gain module and method for producing such a module

Patent metadata

Field	Value
Publication number	US-8929413-B2
Application number	US-201113994645-A
Country	US
Kind code	B2
Filing date	Dec 14, 2011
Priority date	Dec 17, 2010
Publication date	Jan 6, 2015
Grant date	Jan 6, 2015

Abstract

According to one embodiment, the invention relates to a laser gain module ( 1 ) comprising: a laser rod ( 5 ) having a shaft and two optical interfaces ( 7, 9 ) facing each other, the rod ( 5 ) being used for longitudinal or quasi-longitudinal optical pumping; and a metal cooling body ( 3 ), at least one part of which is molded around the laser rod ( 5 ) in order to cover all of the surfaces other than the optical interfaces in such a way that the laser gain module ( 1 ) forms a solid body that cannot be disassembled at ambient temperature.

First claim

The invention claimed is:

1. A laser gain module comprising:
a laser rod comprising two optical interfaces arranged opposing one another, the laser rod being intended to undergo a longitudinal or near-longitudinal optical pumping, and
a metal cooling body at least a part of which is molded around the laser rod so as to cover all surfaces other than optical interfaces in such a manner that the laser gain module forms a non-removable solid body at room temperature.

2. The laser gain module as claimed in claim 1 , wherein the metal cooling body comprises an internal part made of metal material molded around the laser rod and an external part made of metal material in contact with the internal part, a melting point of the metal material forming the internal part being lower than a melting point of the metal material forming the external part.

3. The laser gain module as claimed in claim 2 , further comprising a metal adhesion layer between the internal part of the metal cooling body and the laser rod.

4. The laser gain module as claimed in claim 2 , wherein the metal material forming the external part of the metal cooling body comprises an alloy containing at least one selected from the group consisting of copper, iron, zinc, aluminum, silver, gold, platinum and tin.

5. The laser gain module as claimed in claim 1 , wherein the metal cooling body is formed from a single material as a single part molded around the laser rod.

6. The laser gain module as claimed in claim 5 , wherein the metal material forming the cooling body is made of an alloy containing at least one selected from the group consisting of copper, iron, zinc, aluminum, silver, gold, platinum and tin.

7. The laser gain module as claimed in claim 1 , wherein the laser rod comprises a crystal fiber, whose crystalline matrix is one selected from the group consisting of an oxide, a vanadate, a fluoride, and a tungstate, and comprises rare-earth or metal dopant ions.

8. The laser gain module as claimed in claim 1 , wherein the optical interfaces of the laser rod are covered by a dielectric coating.

9. A laser gain element comprising:
a laser gain module as claimed in claim 1 , and
a cooling block fixed to the laser gain module and structured for circulation of a cooling fluid.

10. A solid-state laser system comprising:
a laser gain module as claimed in claim 1 ; and
a source for emission of a pump beam intended for longitudinal or near-longitudinal pumping of the laser rod.

11. A method for fabricating a laser gain module, comprising:
bringing into contact a laser rod with a metal compound in solid or liquid form to form a rod-metal compound assembly;
heating the rod-metal compound assembly to a temperature at least equal to a melting point of the metal compound, allowing the metal compound to mold around the laser rod;
cooling the rod-metal compound assembly to a temperature lower than the melting point of the metal compound in order to form a non-removable solid body at room temperature; and
cutting and polishing the rod-metal compound assembly so as to form two optical interfaces arranged opposing one another, all surfaces other than the optical interfaces being covered by the metal compound.

12. The fabrication method as claimed in claim 11 , comprising:
depositing of the laser rod into a notch of a mounting made of metal material prior to bringing the laser rod into contact with the metal compound, the metal compound having a melting point lower than that of the metal material from which the mounting is made,
heating of an assembly comprising the mounting, the metal compound, and the laser rod to a temperature lower than that of the melting point of the metal material from which the mounting is made, and
cooling of the assembly in order to form said non-removable solid body at room temperature.

13. The fabrication method as claimed in claim 12 , further comprising, prior to bringing the rod into contact with the metal compound:
coating of all surfaces other than the optical interfaces of the laser rod with a metallic paint allowing adhesion of a brazing material, and
drying of the metallic paint deposited onto the laser rod so as to obtain a metal adhesion layer around the laser rod.

14. The fabrication method as claimed in claim 11 , comprising:
depositing of the laser rod into a crucible prior to bringing the laser rod into contact with the metal compound,
heating of the crucible containing the rod-metal compound assembly to a temperature at least equal to the melting point of the metal compound, and
de-molding of the rod-metal compound assembly after the cooling.

Assignees

• Aubry Nicolas
• Perrodin Didier
• Didierjean Julien
• Fourmigue Jean-Marie
• Balembois François
• Martial Igor
• Fibercryst
• Centre Nat Rech Scient

Inventors

• Aubry Nicolas
• Perrodin Didier
• Didierjean Julien
• Fourmigue Jean-Marie
• Balembois François
• Martial Igor

Classifications

• H01S3/0405

  Conductive cooling, e.g. by heat sinks or thermo-electric elements · CPC title

• H01S3/061

  with elliptical or circular cross-section and elongated shape, e.g. rod · CPC title

• H01S3/09415

  the pumping beam being parallel to the lasing mode of the pumped medium, e.g. end-pumping · CPC title

• H01S3/025

  of solid state lasers, e.g. housings or mountings · CPC title

• H01S3/08072

  Thermal lensing or thermally induced birefringence; Compensation thereof · CPC title