Patent ID: 7084419

Claim:
An apparatus for reading a radiation image formed on a radiation sensitive panel exposed with radial rays penetrated through a subject, the apparatus comprising: a detector to obtain an image signal of the radiation image formed on the radiation sensitive panel by converting the radiation image from the radiation sensitive panel into an electric signal; and a sensitivity compensating section to automatically compensate a sensitivity of the detector based on a radiation sensitive panel exposed with a predetermined dose of radial rays such that (1) the detector obtains a signal by scanning an irradiation area of the radiation sensitive panel with a sensitivity value and the sensitivity compensating section compares the value of the signal with the ideal value of said signal corresponding to the predetermined dose of radial rays and (2) when the value of the signal is not equal to the ideal value, the sensitivity compensating section controls so that the detector obtains another signal by scanning the irradiation area of the radiation sensitive panel with another different sensitivity value different from said sensitivity value by a sensitivity value predetermined depending on a result of a comparison between the value of the signal and the ideal value and the sensitivity compensating section compares the value of another signal with the ideal value, and the sensitivity compensating section repeats the operations (1) and (2) until the value of a signal becomes equal to the ideal value to obtain a signal having a value equal to the ideal value, and determines the sensitivity value applied to obtain the signal having the value equal to the ideal value as a sensitivity compensation value to compensate a sensitivity of the detector.