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:
Feb. 27, 1990
Filed:
Dec. 10, 1987
Applicant:
Inventors:
John P Dakin, Hampshire, GB;
David J Pratt, Suffolk, GB;
Assignee:
Plessey Overseas Limited, Ilford, GB;
Primary Examiner:
Int. Cl.
CPC ...
H01J / ;
U.S. Cl.
CPC ...
250227 ; 250226 ;
Abstract
An optical time domain reflectometry system in which laser level reference signals are derived from the respective laser outputs from the laser sources and fed into a single receiver provided for receiving the back-scattered or returned light along an optical fibre. The receiver is thus continuously calibrated in accordance with the relative intensities of the optical signals at different frequencies being launched into the optical fibre so that the receiver provides an accurate measurement of temperature or other parameter being measured by the system.