Continuous particulate-measuring apparatus using an optoacoustic effect
US4594004A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jun 28, 1983 |
| Grant date | Jun 10, 1986 |
| Priority date | — |
| Expiry date | Jun 28, 2003 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01N2021/1704
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
An apparatus for continuously measuring the concentration of particulates in a sample gas by using an optoacoustic effect. Identical laser rays are directed along two optical paths, and a chopper and an optoacoustic cell are position in the recited order in each of the optical paths. Sample gas containing particulates is introduced into one optoacoustic cell and sample gas from which the particulates have been removed is introduced into the other optoacoustic cell. The respective choppers are driven for producing a chopping action on the respective laser rays at a frequency corresponding to the resonant frequency of the corresponding optoacoustic cells, and the outputs from the cells can be compared for providing an indication of the concentration of the particulates in the sample gas.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.