Particle size detection device having high sensitivity in high molecular scattering environment
US4798465A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Apr 14, 1986 |
| Grant date | Jan 17, 1989 |
| Priority date | — |
| Expiry date | Apr 14, 2006 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01N2021/391
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A detection device is disclosed for determining particle size from particle effected light scattering in a sensing region receiving the particles in a gas carrier, such as air, and a laser beam to illuminate the sensing region. Background light from molecular scattering is reduced to a level that enables light scattered by particles having a size of at least as low as about 0.1 micron to be sensed in a high background of molecular scattering such as, for example, where molecular scattering can exceed the 0.1 micron particle's scattering by one hundred times. High molecular scattering is generated whenever the gas volume being viewed is large as is required for high flow rates, high molecular density (high pressures), or large gas molecules. This high sensitivity at high molecular scattering background is achieved through use of a linear array of detectors positioned, with respect to an imaging system, so that each detector monitors a different portion of the sensing region and provides an electrical output signal indicative of sensed particle presence within that portion monitored. The output signals from the detectors are parallel processed and coupled to a converter which provide…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.