The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Dec. 19, 1989
Filed:
Apr. 05, 1988
Applicant:
Inventors:
Assignee:
Cogent Limited, London, GB;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
G01N / ;
U.S. Cl.
CPC ...
73 2 / ; 324 / ;
Abstract
A gas sensor has a layer of a semiconductor organic polymer, such as polypyrrole which is exposed to a gas to be detected. An alternating electric signal of varying frequency is applied to the sensor by an analyser, which detects the change in impedance characteristics of the sensor. The characteristics obtained are compared by microcomputer with reference characterisitcs stored in a memory. The resulting difference spectra depend on the gas in contact with the sensor and so the gas can be detected.