Photoacoustic gas analyzer

申请公布号：

US4818882(A)

申请号：

US19870052596

申请日期：

1987.05.20

申请公布日期：

1989.04.04

申请人：

AKTIESELSKABET BRUEL & KJAER

发明人：

NEXO, STEN A.;CHRISTENSEN, JOERGEN;JORGENSEN, IB E.

分类号：

G01N21/00;G01J1/44;G01N21/05;G01N21/17;G01N21/31;G01N29/00;(IPC1-7):G01N21/00

主分类号：

G01N21/00

摘要：

A photoacoustic gas analyzer comprising a measuring chamber, a modulated light source, and at least one microphone in connection with the measuring chamber and measuring the changes of pressure caused by the absorption of the light in the chamber. The measuring chamber comprises an inner surface with a reflecting coating. The measuring signal is thereby proportional to the gas concentration and is not provided as the difference between two almost equal values. As a result it is possible to measure small gas concentrations provided the light intensity within the measuring chamber suffices.