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. 11, 2005
Filed:
Mar. 20, 2002
Ralf Schmidt, Aachen, DE;
Kai Eck, Aachen, DE;
Ralf Schmidt, Aachen, DE;
Kai Eck, Aachen, DE;
Koninklijke Philips Electronics N.V., Eindhoven, NL;
Abstract
The invention relates to a method for the calibration of a radiation sensor, in which method a first calibration takes place with external radiation x and an internal signal s of the radiation sensor, and in which later calibrations are carried out exclusively with the internal signal. This enables the calculation of an approximate value x*(t) for the quantity of radiation x(t) absorbed in a radiation sensor () while taking into account a behavior of the radiation sensor that changes in time. First the primary characteristic f(x) is measured at a first instant t; this characteristic describes the dependency of an output signal o on the absorbed quantity of radiation x. At the same time the secondary characteristic g(s) is measured, which characteristic describes the dependency of the output signal o on an internal signal s. The signals s and x should together form an intermediate signal w that is further processed with a function D(w,t) that varies in time in order to form the output signal o. The secondary characteristic is measured again at a later instant tafter the occurrence of aging; this measurement can be performed without utilizing (X) radiation. The calculation of the approximate value for the absorbed quantity of radiation can then be performed in conformity with the following formula: