High power semiconductor laser diodes

US8320419B2 · kind B2 · utility

Assignee

• OCLARO TECHNOLOGY LIMITED · GB

Inventors

• Martin Krejci · Zürich, CH
• Norbert Lichtenstein · Thalwil, CH
• Stefan Weiss · Trostberg, DE
• Julien Boucart · Milpitas, US
• René Todt · Adliswil, CH

Key dates

• Filing date: Sep 1, 2010
• Grant date: Nov 27, 2012
• Expiry date: Feb 5, 2031

Classification

• Technology area (CPC H): Electricity
• CPC primary: H01S2301/14
• WIPO field: Optics
• WIPO sector: Instruments

Abstract

A high power laser source comprises a bar of laser diodes having a first coefficient of thermal expansion CTEbar on a submount having a second coefficient CTEsub and a cooler having a third coefficient CTEcool. The submount/cooler assembly shows an effective fourth coefficient CTEeff differing from CTEbar. This difference leads to a deformation of the crystal lattice of the lasers' active regions by mechanical stress. CTEeff is selected to be either lower than both CTEbar and CTEcool or is selected to be between CTEbar and CTEcool. The submount may either comprise layers of materials having different CTEs, e.g., a Cu layer of 10-40 μm thickness and a Mo layer of 100-400 μm thickness, or a single material with a varying CTEsub. Both result in a CTEsub varying across the submount's thickness.