External cavity tunable compact Mid-IR laser
US7535936B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Aug 5, 2005 |
| Grant date | May 19, 2009 |
| Priority date | — |
| Expiry date | Feb 5, 2026 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01S5/3402
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A compact mid-IR laser device utilizes an external cavity to tune the laser. The external cavity may employ a Littrow or Littman cavity arrangement. In the Littrow cavity arrangement, a filter, such as a grating, is rotated to provide wavelength gain medium selectivity. In the Littman cavity arrangement, a reflector is rotated to provide tuning. A quantum cascade laser gain medium provides mid-IR frequencies suitable for use in molecular detection by signature absorption spectra. The compact nature of the device is obtained owing to an efficient heat transfer structure, the use of a small diameter aspheric lens for both the output lens and the external cavity lens and a monolithic assembly structure to hold the optical elements in a fixed position relative to one another. The compact housing size may be approximately 20 cm×20 cm×20 cm or less. Efficient heat transfer is achieved using a thermoelectric cooler TEC combined with a high thermal conductivity heat spreader onto which the quantum cascade laser gain medium is thermally coupled. The heat spreader not only serves to dissipate heat and conduct same to the TEC, but also serves as an optical platform to secure the optical eleme…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.