Laser-integrated balance detection for self-mixing interferometry
US11909171B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Mar 31, 2021 |
| Grant date | Feb 20, 2024 |
| Priority date | — |
| Expiry date | Mar 23, 2042 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01S5/183
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
An optical sensor system includes a set of epitaxial layers formed on a semiconductor substrate. The set of epitaxial layers defines a semiconductor laser having a first multiple quantum well (MQW) structure. Electromagnetic radiation is generated by the first MQW structure, emitted from the first MQW structure, and self-mixed with a portion of the emitted electromagnetic radiation that is returned to the first MQW structure. The set of epitaxial layers also defines a second MQW structure operable to generate a first photocurrent responsive to detecting a first emission of the semiconductor laser, and a third MQW structure operable to generate a second photocurrent responsive to detecting a second emission of the semiconductor laser. The optical sensor system also includes a circuit configured to generate a self-mixing interferometry (SMI) signal by combining the first photocurrent and the second photocurrent.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.