Spatial modulation of light to determine object length
US9952033B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Feb 14, 2014 |
| Grant date | Apr 24, 2018 |
| Priority date | — |
| Expiry date | Aug 21, 2036 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01N2015/1493
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
Spatially modulated light emanating from an object moving along a flow path is used to determine various object characteristics including object length along the flow direction. Light emanating from at least one object moving along in a flow path along a flow direction of a spatial filter is sensed. The intensity of the sensed light is time modulated according to features of the spatial filter. A time varying electrical signal is generated which includes a plurality of pulses in response to the sensed light. Pulse widths of at least some of the pulses are measured at a fraction of a local extremum of the pulses. The length of the object along the flow direction is determined based on the measured pulse widths.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.