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:
Jan. 20, 2004
Filed:
Sep. 25, 2000
Stuart Charles Murray, West Bridgford, GB;
Lattice Intellectual Property Limited, London, GB;
Abstract
A water detecting apparatus includes a source of infra-red radiation which is reflected off an inner surface of a pipe wall onto a mirror directing the infra-red signal along a path to an infra-red detector connected by an electrical signal path to an electronic control. The path is interrupted by a rotating chopper having windows occupied by two optical filters. The first optical filter only passes an infra-red signal of wavelength 1900 nm which is absorbed by water, while the second optical filter only passes an infra-red signal of wavelength 2200 nm, another wavelength absorbed by water, but not to the same extent as the 1900 nm wavelength. The 2200 nm wavelength serves as a reference signal. When the strength of the infra-red signal path by the first optical filter decreases in relation to the strength of the infra-red reference signal path by the second optical filter, this is due to water on the surface absorbing the 1900 nm wavelength more than the 2200 nm wavelength, and the electronic control causes an indicator to indicate the presence of the water.