| 摘要 |
An image sensor can reduce fixed pattern noise (FPN) caused by transistors used for reading pixel signals. The image sensor comprises photodiodes D1, D2, . . . connected to a precharge line LPR through respective precharge transistors (Tr1)1, (Tr1)2; and pixel amplification transistors (Tr2)1, (Tr2)2, . . . , one end thereof being connected to a signal read line LRE, the other end thereof being grounded through respective pixel switching transistors (Tr3)1, (Tr3)2, . . . , and the gates thereof being connected to respective nodes between the precharge transistors Tr1, (Tr1)2, . . . and the photodiodes D1, D2, . . . According to signals provided by a timing signal generator 3, the pixel switching transistors (Tr3)1, (Tr3)2, . . . are sequentially turned ON and OFF one after another. During ON and OFF states of each of the pixel switching transistors, a correlated double sampling circuit provides a difference between values read out of the signal read line LRE.
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