Patent ID: 6600161
Filing Date: 2003-07-29
Classification: G01T

Abstract:
A method of imaging by ionizing apparatus, the method comprising the following steps:causing a detection signal S(t) to be generated by at least one detection cell, said detection signal comprising a succession of individual detection signals s(t) generated by the detection cell each time said detection cell detects an ionizing ray coming from a certain observation zone and having energy lying in a predetermined range of energy values; and processing the detection signal S(t) to obtain at least one measurement of the ionizing radiation flux detected by the detection cell during a measurement period T so as to generate an image of the observation zone, said image comprising at least one point given an intensity value which is a function of at least said ionizing radiation flux as measured by the detection cell during the detection period; wherein, during each measurement period, two measurements are performed simultaneously on the ionizing radiation flux detected by a given detection cell, specifically: a first measurement f1 proportional to the integral of the detection signal S(t) generated by the detection cell during the measurement period T; and a second measurement f2 proportional to the number of successive detection signals s(t) during the same measurement period T; and wherein the intensity value for each image point is a predetermined function of at least one pair of first and second measurements f1, f2 corresponding to said point, said predetermined function giving increasing weight to the first measurement f1 compared with the second measurement f2 while a first estimate fe of the ionizing radiation flux increases, which first estimate is a function of at least one of the first and second measurements f1 and f2, and said intensity at each point of the image being different from the first and second measurements f1 and f2, at least in a predetermined range of values of said first estimate fe of the ionizing radiation flux.