Patent ID: 8452069

Claim:
A method of eliminating the deteriorating effect of afterglow in a radiation image of a patient that has been stored in a photostimulable phosphor screen comprising: line-wise scanning a phosphor screen with a deflected laser beam so as to stimulate a recorded phosphor radiation image of a patient; converting, by a photomultiplier, image-wise modulated light emitted by said phosphor screen upon stimulation into an electric signal representation, wherein the electric signal representation includes parts corresponding to an instantaneous pixel value and an afterglow of previously scanned pixels; determining, by the image processor, for each pixel of the electric signal representation, the amount of afterglow generated by all previously scanned pixels in the same line of pixels prior to an instantaneous pixel, wherein said amount of afterglow is equal to Σe −t/tau ·f(t) , where tau is the time constant of the afterglow, f(t) is the amount of emitted light as a function of time during scanning, and Σ is the summation for all pixels in the same line that were scanned prior to the instantaneous pixel; multiplying, by an image processor, for each pixel of the electric signal representation, each determined amount of afterglow with a constant amplitude (Amp) value, wherein the constant amplitude value is an optimal value obtained through a fitting procedure applied to a preset amplitude value; subtracting, by the image processor, for each pixel of the electric signal representation, said determined amount of afterglow multiplied by said constant amplitude (Amp) value from Σe −t/tau ·f(t) Σ Afterglow ⁡ ( i + 1 ) = Pixel ⁡ ( i + 1 ) * tau + afterglow ⁡ ( i ) 1 + tau , the instantaneous pixel value.