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:
Aug. 04, 1992
Filed:
Sep. 13, 1990
Cornelis S Kooijman, Eindhoven, NL;
U.S. Philips Corporation, New York, NY (US);
Abstract
A measuring device comprises a detector (1) for a quantity x to be measured, which detector is adapted to produce two signals I.sub.1 and I.sub.2 which relate to x as x=(I.sub.1 -I.sub.2)/(I.sub.1 +I.sub.2). The device further comprises a processing circuit (3) which includes a first and a second logarithmic converter (9, 11) whose inputs receive input signals V.sub.1 and V.sub.2 which are proportional to the first and the second measuring signal I.sub.1, I.sub.2, respectively. The outputs of the logarithmic converters are connected to first and second inputs (12A, 12B) of a subtractor circuit (13) which produces at its output (14) an output signal U(x) which depends on the quantity x to be measured. If a subtractor circuit is used which is adapted to determine the hyperbolic tangent of the difference between the signals logV.sub.1 and logV.sub.2 present at its two inputs (12A, 12B), the relationship between u(x) and x will be linear.