Self-mixing inteferometry sensor module, electronic device and method of determining an optical power ratio for a self-mixing inteferometry sensor module
US11927441B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Aug 19, 2022 |
| Grant date | Mar 12, 2024 |
| Priority date | — |
| Expiry date | Aug 19, 2042 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01S17/32
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A self-mixing interferometry sensor module, comprising a light emitter (LE), a detector unit (DU) and an optical element (OE), wherein the light emitter (LE) is operable to emit coherent electromagnetic radiation towards an external object (ET) to be placed outside the sensor module and undergo self-mixing interference, SMI, caused by reflections of the emitted electromagnetic radiation from the external object back inside the sensor module. The detector unit (DU) is operable to generate output signals indicative of an optical power output of the light emitter (LE) due to the SMI. The optical element (OE) is aligned with respect to the light emitter (LE) such that a first fraction of electromagnetic radiation is directed towards the external target (ET) or the light emitter (LE) and a second fraction of electromagnetic radiation is directed towards the detector unit (DU). An optical power ratio determined by the first and second fractions meets a pre-determined value.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.