| 摘要 |
PURPOSE:To realize noise suppression with simple circuit constitution by obtaining a video signal, an output signal including a vertical smear noise fixed pattern noise (FPN) and an output signal comprising said two types of noise only not including a video signal from a sensor and allowing the said two output signal to cancel the noise. CONSTITUTION:A signal superimposing the video signal, FPN and vertical smear noise is outputted from one of output terminals 9, 10 during one horizontal scanning period in a sensor 1 and only the FPN, vertical smear not including the video signal are read from the other terminal at the same time. Then output signals of the terminals 9, 10 are amplified respectively to form signals 9', 10', each subtraction output is obtained for the signals 9', 10' at subtractors 12, 13, they are changed over by a switch 14 to obtain an output 15. In this case, the switch 14 is operated in synchronizing with the pulse having a period frequency-dividing the horizontal period of a referance clock. Since the vertical signal line where the vertical smear of the outputs 9, 10 is generated is closed together, the vertical smear is cancelled at the output of the circuits 12, 13. Since the FPN is outputted alternately at adjacent horizontal scanning period and is of opposite polarity waveform of the same phase and amplitude, the FPN is erased visually. |
