| 摘要 |
PURPOSE:To attain ease of signal processing at the post-stage of an image sensor by driving a shift register extracting sequentially an electric charge generated at a photo sensing section with the 1st shift pulse whose duty ratio (d) is set to a value in excess of 0.5 and the 2nd shift pulse opposite in polarity to that of the 1st shift pulse and whose duty ratio is set to 1-d, to prevent noise from being generated at the effective section of output signal of the image sensor. CONSTITUTION:The duty ratio (d=t3/t) of shift pulses phi1, phi2 is set as shown in the fig., where (t) is a transfer time per bit of shift pulses phi1, phi2 driving a shift register section 4. In driving the register at a high speed while using 6MHz of frequency for the shift pulses phi1, phi2 for example, the duty rario of the shift pulse phi1 is set to 0.6-0.7 and the duty ratio of the shift pulse phi2 is set 1-0.6-1- 0.7. Thus, a switching noise CN generated at the changeover of the shift pulses phi1, phi2 is generated at the tail end of the transfer time (t).
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