SOLID-STATE IMAGE SENSOR, METHOD OF CONTROLLING THE SAME, AND STORAGE MEDIUM

摘要

A solid-state image sensor comprises unit pixels, each unit pixel including photodiodes, transfer switches, a floating diffusion portion, and reset means, and an AD converter, wherein the AD converter includes a reference signal generator and a comparator that compares the reference signal and analog signal and vary an output depending on a magnitude relationship, the floating diffusion portion accumulates a first signal obtained by transferring a signal of at least one of the photodiodes, and adds, to the first signal, a second signal obtained by transferring a signal of at least one of the photodiodes, and the AD converter operates in a first AD conversion mode when AD-converting the first signal, and operates in a second AD conversion mode when AD-converting the second signal.

主权项

1. A solid-state image sensor comprising:
a pixel portion in which unit pixels are arranged in matrix, each unit pixel including a plurality of photodiodes, transfer switches respectively provided for the plurality of photodiodes, a floating diffusion portion commonly connected via the transfer switches, and reset means for resetting the floating diffusion portion and an AD converter configured to convert an analog signal from said floating diffusion portion into a digital signal and read out the digital signal, wherein said AD converter includes a reference signal generator configured to generate a reference signal whose electric potential varies with a predetermined slope as a time elapses, and a comparator configured to compare the reference signal and the analog signal and vary an output depending on a magnitude relationship, said floating diffusion portion accumulates a first signal obtained by transferring a signal of at least one of the plurality of photodiodes of said pixel portion via said transfer switch, and adds, to the first signal, a second signal obtained by transferring a signal of at least one of the plurality of photodiodes via said transfer switch in a state in which the first signal is not reset and accumulates the second signal, and said AD converter operates in a first AD conversion mode when AD-converting the first signal, and operates in a second AD conversion mode different from the first AD conversion mode when AD-converting the second signal.