The invention relates to an
image sensor with matrix readout including a matrix of elementary photodetectors (P) connected through at least a
bus (Bpel) to a remote
integrator (I) which converts the
signal of each elementary
photodetector into a
voltage, characterized in that it includes, between the end of the
bus and the input of the
integrator, an
impedance matching device (D) with low output
capacitance, delivering at its output, during the time for converting a
photodetector signal, a variation of charge which corresponds to an affine function of the charge present at the input of said matching device, wherein this charge variation is determined by: <math-cwu id="MATH-US-00001"> <number>1< / number> ∫ t = 0 t = Tconv Iinj ( t ) · ⅆ t = ∫ t = 0 t = Tconv I int ( t ) · ⅆ t <mathematica-file id="MATHEMATICA-00001" file="US20010048065A1-20011206-M00001.NB" / > <image id="EMI-M00001" wi="216.027" he="19.93005" file="US20010048065A1-20011206-M00001.TIF" imf="TIFF" ti="MF" / > < / math-cwu> where Iinj is the instantaneous current of the
bus, injected at the input of the
impedance matching device, Iint is the instantaneous current at the input of the
integrator and Tconv is the conversion time.