Patent ID: 6801647
Filing Date: 2004-10-05
Classification: G06T

Abstract:
A method for evaluating a digital radiation image which obtains the digital radiation image from a radiation image recorded with a given dose exposed to a radiation and then evaluates thus obtained digital radiation image, comprising the steps of:recording previously at least two radiation images with different exposed doses of the radiation; obtaining at least two digital radiation images from said at least two radiation images; determining a value of evaluation of at least one of the granularity and the image quality of the digital radiation image for each of the thus obtained at least two digital radiation images to obtain at least two values of evaluation; constructing from said at least two values of evaluation a correction curve for the value of evaluation to the exposed dose of the radiation; and calculating by means of said correction curve the value of evaluation of said at least one of the granularity and the image quality of the digital radiation image obtained from the radiation image recorded with the given dose exposed to the radiation, wherein said digital radiation image is a digital radiation image produced by objecting to predetermined processes the radiation image recorded with a phosphor material that emits stimulated light in proportion to the exposed dose of the radiation, said value of evaluation is a square value of RMS granularity or a value of a Wiener spectrum at each frequency for evaluating the granularity of the digital radiation image, said correction curve for the value of evaluation to the exposed dose of the radiation X is expressed as A/X+B (where A and B are constants) and constructed by determining the constants A and B from said at least two values of evaluation.