Portable analyzer for determining size and chemical composition of an aerosol
US5998215A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Oct 3, 1997 |
| Grant date | Dec 7, 1999 |
| Priority date | — |
| Expiry date | Oct 3, 2017 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T436/24
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A portable analyzer for determining the size and chemical composition of particles suspended in an aerosol. The aerosol is accelerated through a nozzle and skimmers, to produce a well-defined beam of particles, the speed of which is inversely related to the particle size. A dual-beam laser system positioned along the beam path detects light scattered from each particle, to determine the particle's velocity and thus its aerodynamic size. The laser system also triggers a laser to produce a beam that irradiates the particle, to desorb it into its constituent molecules. The particle is desorbed in a source region of a bipolar, time-of-flight mass spectrometer, which provides a mass-to-charge spectrum of the desorbed molecule, thereby chemically characterizing the material of the particle. Several structural features provide sufficient ruggedness to allow the analyzer to be easily used in the field with minimum calibration and maintenance.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.