Diode laser-based chemical and biological sensor
US5766956A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | May 27, 1997 |
| Grant date | Jun 16, 1998 |
| Priority date | — |
| Expiry date | May 27, 2017 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01N2201/0612
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A-compact, diode laser-based sensor has applications in biological and chemical analysis. Unlike existing optical waveguide-based sensors, no external coupling to external optical fibers or waveguides is required to perform optical chemical, immunological or nucleic acid-based assay or to detect the presence of toxic or otherwise important chemicals. The sensor includes a surface-sensitive diode laser having a substrate layer, an n-contact layer positioned on a bottom surface of the substrate, an n-clad layer overlying the top surface of the substrate, a first guide layer overlying the n-clad layer, a quantum well layer overlying the first guide layer, a second guide layer overlying the first quantum well layer, a p-clad layer overlying the second guided layer and a p-doped cap layer overlying the p-clad layer. A pair of electrodes separated by a surface-sensitive region is positioned on the cap layer. The surface active region includes an oxide layer grown on the thick cap layer and an absorbing or non-absorbing film deposited on the oxide layer. For internal reflection, inorganic material coatings are applied to end facets or Bragg reflectors are etched in the cap layer. Detector…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.