To provide a solid state image pickup device having a linear log characteristic capable of widening a dynamic range.
In a solid state image pickup device, when a judgment part 14 determines that a TG6 is in a high-luminance state, the TG 6 increases an electric current generated by a current source IS comparing to a low luminance exposure state, to shorten a settling period of a capacitor CIN. As a result, a sample hold period for sampling and holding a noise signal by a column ADC 31 is shortened, which reduces signal charge amount overflowed from PD and flowed into FD in a reading period. Consequently, degradation of noise signal level is suppressed, and black-and-white inversion phenomenon is suppressed, thus, the dynamic range is widened.
MORIMOTO TAKASHI
IWAMOTO TSUYOSHI
Masataka Otani
Koji Nishitani
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