| 摘要 |
PURPOSE:To eliminate noise caused by variance of sensors between electrodes and discordance of scanning pulses etc. by switching an MOS switch connected in series to individual sensor element of an MOS type image sensor twice consecutively, and reading the difference between signals of the first time and the second time. CONSTITUTION:A pre-amplifier 13 that amplifies signals from a signal line and a driving circuit 17 that drives the MOS switch of the sensor are provided in the noise detecting circuit of a one-dimensional or two-dimensional MOS image sensor. Reset pulse is applied from the circuit 17 to the amplifier 13, amplified by the amplifier 13 and integrated output is applied to sample holding circuits A14 and B15. Each of sampling pulses H, I is given from the circuit 17 to circuits A14, B15 respectively, and the signal due to the switching of the first time is held by the circuit A14 and the signal due to the switching of the second time is held by the circuit B15. The difference between the first and second signals is read by a differential amplifier 16, and noise caused by scattering of the sensor and discordance of scanning pulses is eliminated perfectly. |
