Particulate matter velocity measurement and size estimation using parallel self-mixing sensing
US11280714B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Aug 21, 2019 |
| Grant date | Mar 22, 2022 |
| Priority date | — |
| Expiry date | Dec 3, 2039 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01N2015/1454
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
An apparatus for particulate matter (PM) measurement includes a first light source to generate a first light beam and a second light source disposed at a first distance from the first light source to generate a second light beam in parallel to the first light beam to illuminate a PM. The apparatus further includes a first light detector to measure a first timing corresponding to a first self-mixing signal resulting from a reflection and/or back-scattering of the first light beam from a PM, and a second light detector to measure a second timing corresponding to a second self-mixing signal resulting from a reflection and/or back-scattering of the second light beam from the PM. A processor can determine a first velocity of the PM based on a spatial separation between centers of the first light beam and the second light beam and a temporal separation between the first timing and the second timing.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.