Patent ID: 7016466

Claim:
A method for the automatic detection of the start of irradiation in an x-ray imaging system for digital radiography, the x-ray imaging system comprising an x-ray imager matrix that is electrically coupled to a control unit, the method comprising the steps of: reading out an x-ray imager matrix to create a blemishes map of pixels or sections of the x-ray imager matrix that show blemish defects; reading out the x-ray imager matrix to produce output elements O(i,j) at each readout cycle i, where j is the index of the output element, each output element O(i,j) corresponding to a pixel or section of the x-ray imager matrix; comparing the output elements O(i,j) with a temperature corrected first threshold TH 1 c(i), wherein the temperature corrected first threshold TH 1 c(i) at the present readout cycle i is a function f[TH 1 c(i−1), T(i)] of the temperature corrected first threshold TH 1 c(i−1) at the previous readout cycle i−1 and a simulated temperature T(i) at the present readout cycle i; counting the number of output elements O(i,j) that exceed the temperature corrected first threshold TH 1 c(i), wherein output elements O(i,j) that correspond to pixels or sections of the x-ray imager matrix which are identified as blemish defects in the blemishes map are rejected even if their corresponding output elements O(i,j) exceed the temperature corrected first threshold TH 1 c(i); identifying a start of irradiation in response to a determination that the counted number of output elements O(i,j) exceeds a second threshold TH 2 ; and repeating the steps of reading out the x-ray imager matrix to produce output elements O(i,j), comparing the output elements O(i,j) with a temperature corrected first threshold TH 1 c(i), counting the number of output elements O(i,j) that exceed the temperature corrected first threshold TH 1 c(i), and identifying a start of irradiation in response to a determination that the counted number of output elements O(i,j) exceeds a second threshold TH 2 , upon a determination that the counted number of output elements O(i,j) is less than a second threshold TH 2 .