| 摘要 |
PURPOSE:To constitute a digital radiography device having a dynamic range which covers widely the dose of X rays, by connecting two capacitors at least in parallel to a photoelectric transducer and changing storage capacities in accordance with the dose of irradiated X rays. CONSTITUTION:Switches Sc1-Sc128 are opened in case of radiographing with the small dose of X rays. In case of radiographing with a large dose of X rays, switches Sc1-Sc128 are closed to increase capacities of capacitors connected in parallel to photoelectric transducers Pd1-Pd128. Since capacities are increased by connecting capacitors Sc1-Sc128 in this manner, the charged electric charge is not saturated though the dose of incident X rays is large, and the S/N ratio is not damaged by opening switches Sc1-Sc128 though the dose of incident X rays is small. |
