| 摘要 |
PROBLEM TO BE SOLVED: To acquire sufficiently a noise reduction effect by providing LPF in an X-ray image sensor or the like. SOLUTION: When reset (initialization) of a charge sensitive amplifier (CSA)41 is removed, an output potential (potential at the point A) of the CSA 41 is raised instantly by the charge flowing in from a data line of the image sensor. On the other hand, the potential at the interval (point B) between a resistance R1 and a capacitor C1 in the LPF 42 is raised more slowly than the potential at the point A by a time constant of the LPF 42. Accordingly, reset (initialization) of the first amplifier MA1 on the initial stage in a main amplifier (MA) 43 is removed (a reset switch MASW1 is switched to the off-state) after the potential at the point B approaches the potential at the point A sufficiently after reset finish of the CSA 41. Hereby, since only a small amount of the charge remains in the capacitor C1, a signal charge flowing into the capacitor C1 thereafter can be detected accurately. COPYRIGHT: (C)2006,JPO&NCIPI
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