| 摘要 |
PURPOSE:To prevent the deterioration of the quality of an image obtained by image processing based on plural images by energy subtraction processing and superimposing processing. CONSTITUTION:By simultaneously radiating radioactive rays transmitted through a subject to two superposed stimulable phosphor sheets 4A and 4B, the radiograph expressing the subject is accumulated and recorded on the sheets 4A and 4B. The sensitivity of a read condition in the case of obtaining an image signal from the sheet 4B positioned far from a radioactive ray source out of the sheets 4A and 4B is made higher than that in the case of obtaining the image signal from the sheet 4A positioned close to the radiactive ray source so as to read the image signal expressing the radiograph. As for a method for making the sensitivity of the read condition larger, read is executed by making the light intensity of a laser beam source 10 higher, increasing the sensitivity of a photomultiplier 15, or making the amplification factor of a logarithmic amplifier 16 large. |
