VCSEL and VCSEL array having integrated microlenses for use in a semiconductor laser pumped solid state laser system

• US 20050025211A1
• Filed: 08/23/2004
• Published: 02/03/2005
• Est. Priority Date: 07/12/2000
• Status: Abandoned Application

• Current Assignee: Princeton Optronics Inc (Ams-Osram AG)
• Original Assignee: Princeton Optronics Inc (Ams-Osram AG)
• Inventors: Zhang, Jiamin, Watkins, Laurence S., Zhang, Kaiyan, Ghosh, Chuni L.
• Application Number:
  US10/922,920
• Publication Number:
  US 20050025211A1
• Time in Patent Office: Days
• US Class Current: 372/101
• CPC Class Codes: H01S 3/0064 Anti-reflection devices, e.g. optical isolaters absorbing layers for marking or protecting purposes in laser working B23K26/50; magneto-optical non-reciprocal devices G02F1/093, G02F1/0955
• CPC Class Codes: H01S 3/025 of solid state lasers, e.g. housings or mountings
• CPC Class Codes: H01S 3/0604 in the form of a plate or disc
• CPC Class Codes: H01S 3/09415 the pumping beam being parallel to the lasing mode of the pumped medium, e.g. end-pumping
• CPC Class Codes: H01S 3/1062 using a controlled passive interferometer, e.g. a Fabry-Perot etalon
• CPC Class Codes: H01S 5/0207 Substrates having a special shape
• CPC Class Codes: H01S 5/024 Arrangements for thermal management
• CPC Class Codes: H01S 5/18308 having a special structure for lateral current or light confinement
• CPC Class Codes: H01S 5/18388 Lenses
• CPC Class Codes: H01S 5/423 having a vertical cavity

Abstract

A vertical cavity surface emitting laser (VCSEL) device with improved power and beam characteristics. The VCSEL device contains one VCSEL or an array of VCSELs. Each VCSEL has a corresponding integrated microlens, and a heat sink is attached to the device side of the VCSEL device. The heat sink allows improved heat dissipation, and therefore provides improved power characteristics of the VCSEL device output laser beam. The microlens or microlens array allows easier and more compact focussing of the VCSEL device output laser beam. The VCSEL device can be used in a variety of optical systems, and its improved power and focusing characteristics provide a compact, low power, low cost laser system.

Claims

1. A structure within a vertical cavity surface emitting laser (VCSEL) device, the structure comprising:

a substrate having a microlens formed therein;

a first mirror region formed on said substrate;

an active layer formed on said first mirror region;

a second mirror region formed on said active layer; and

a heat sink formed on said second mirror region.

2. A structure in accordance with claim 1, further comprising:

a contact layer on the second mirror region,

a layer on a surface of the heat sink facing the second mirror region; and

a bonding material which bonds the metal layer and the contact layer.

3. A structure in accordance with claim 1, wherein said heat sink comprises diamond.

4. A structure in accordance with claim 1, wherein the microlens is a refractive or diffractive microlens which reduces a divergence of the output laser beam.

5. A structure in accordance with claim 1, wherein the microlens is a refractive or diffractive microlens which focuses the output laser beam.

6. A structure in accordance with claim 5, wherein the microlens is a diffractive microlens which comprises a plurality of concentric stepped structures formed in the substrate.

7. In a VCSEL device array having a plurality of VCSEL devices arranged on a substrate, each VCSEL device outputting an individual output laser beam so that the VCSEL device array outputs a composite output laser beam composed of the individual output laser beams, a structure within each member of a subset of the plurality of the VCSEL devices comprising:

a microlens formed within said substrate;

a first mirror region, formed on said substrate;

an active layer formed on said first mirror region;

a second mirror region formed on said active layer; and

a heat sink formed on said second mirror region.

9. A structure within a VCSEL device array in accordance with claim 7, wherein the heat sink comprises diamond.

10. A structure within a VCSEL device array in accordance with claim 7, wherein the microlens is a refractive microlens which reduces the divergence of the individual output laser beam, to thereby reduce the divergence of the composite output laser beam.

11. A structure within a VCSEL device array in accordance with claim 7, wherein the microlens array converges the individual output beams of the VCSEL devices, to thereby focus the composite output laser beam of the VCSEL device array.

12. A VCSEL device array in accordance with claim 7, wherein the microlens array reduces the divergence of the composite output beam of the VCSEL device array to less than 1 degree, and thereby collimates the composite output beam of the VCSEL array.

8. A structure within a VCSEL device array in accordance with clam 7, further comprising:

a contact layer on the second mirror region,

a metal layer on a surface of the heat sink facing the second mirror region; and

a bonding material which bonds the metal layer and the contact layer.

13-29. -29. (Cancel).