Conductively cooled, diode-pumped solid-state slab laser

• US 4,949,346 A
• Filed: 08/14/1989
• Issued: 08/14/1990
• Est. Priority Date: 08/14/1989
• Status: Expired due to Term

• Current Assignee: Laser Energetics, Inc.
• Original Assignee: Alliedsignal Inc.
• Inventors: Rapoport, William R., Kuper, Jerry W.
• Primary Examiner(s): Sikes, William L.
• Assistant Examiner(s): Epps, Georgia Y.
• Application Number:
  US07/393,185
• Time in Patent Office: 365 Days
• Field of Search: 372/34, 372/36, 372/66, 372/69, 372/72, 372/75
• US Class Current: 372/36
• CPC Class Codes: H01S 3/0405 Conductive cooling, e.g. by heat sinks or thermo-electric elements
• CPC Class Codes: H01S 3/042 for solid state lasers H01S3/0401 takes precedence
• CPC Class Codes: H01S 3/0606 with polygonal cross-section, e.g. slab, prism H01S3/0604 takes precedence
• CPC Class Codes: H01S 3/08072 Thermal lensing or thermally induced birefringence; Compensation thereof
• CPC Class Codes: H01S 3/08095 Zig-zag travelling beam through the active medium
• CPC Class Codes: H01S 3/0933 of a semiconductor, e.g. light emitting diode
• CPC Class Codes: H01S 3/094057 by tapered duct or homogenized light pipe, e.g. for concentrating pump light
• CPC Class Codes: H01S 3/0941 of a laser diode

Abstract

A conductively cooled, optically diode-pumped slab laser comprises a slab laser host 1 having transparent, thermally conductive heat sink means 2 bonded to its pump faces. Semiconductor lasers or light emitting diodes 3 are mounted on the heat sink means for generating pumplight which is transmitted through the heat sink means 2 into laser host 1 to cause lasing. Heat flow within the laser host 1 is substantially bi-directional, thereby minimizing optically harmful thermal distortion of the host. The apparatus can function as laser amplifier, laser oscillator or combined oscillator/amplifier.

Claims

1. A conductively cooled, optically diode-pumped slab laser apparatus comprising, in combination:

(a) an elongated slab of active laser host having two opposite ends, two opposed sides, and a pair of parallel, optically plane faces extending along its length for receiving radiation for optical pumping of the host, and for acting as total internal reflective surfaces for creating internal optical paths;

(b) first and second transparent, thermally conductive solid heat sink means, each having an optically plane face which is dimensioned to match and is bonded to a parallel optically plane face of said laser host by means of a bonding agent having a rafractive index which is smaller than the refractive index of the laser host, said heat sink means having a substantially flat surface opposite the one cavity optically plane face for mounting semiconductor diode pumping means; and

(c) semiconductor diode pumping means mounted on said heat sink means for exciting the laser host.

2. The apparatus of claim 1, wherein said laser host is selected from the group consisting of alexandrite, emerald and Nd:

YAG.

3. The apparatus of claim 1, wherein the material of construction of said heat sink means is selected from the group consisting of fused silica and sapphire.

4. The apparatus of claim 1, wherein said laser host is selected from the group consisting of alexandrite, emerald and Nd:

YAG, and wherein the material of construction of said heat sink means is selected from the group consisting of sapphire and fused silica.

5. The apparatus of claim 1 further provided with thermal insulating means covering said two opposed sides of said elongated slab of laser host.

6. The apparatus of claim 5, wherein said laser host is selected from the group consisting of alexandrite, emerald and Nd:

YAG, and wherein the material of construction of heat sink means is selected from the group consisting of sapphire and fused silica.

7. The apparatus of claim 5, wherein said semiconductor diode pumping means is a semiconductor laser, wherein said laser host is alexandrite, and wherein the material of construction of said heat sink means is selected from the group consisting of sapphire and fused silica.

8. The apparatus of claim 5, wherein said semiconductor diode pumping means is a diode laser, wherein said laser host is Nd:

YAG, and wherein said heat sink means is made of sapphire or fused silica.

9. The apparatus of claim 5, wherein said light emitting diode is an InAlGaAs semiconductor diode, wherein said laser host is alexandrite, and wherein said heat sink means is made of a material selected from the group consisting of sapphire and fused silica.

10. The apparatus of claim 7, wherein said heat sink means is made of sapphire.