Method of determining the quantity of radiation absorbed by a radiation sensor

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 (10) while taking into account a behavior of the radiation sensor that changes in time. First the primary characteristic ft1(x) is measured at a first instant t1; this characteristic describes the dependency of an output signal o on the absorbed quantity of radiation x. At the same time the secondary characteristic gt2(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 t3 after 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: 1 x * ⁢ ( t ) := f t 1 - 1 ⁢ ( g t 2 ⁢ ( g t 3 - 1 ⁢ ( o ⁢ ( t ) ) ) )

Dependencies are inferred from the claim text.