An image pickup device may include: an image capturing unit; a reference signal generation unit; a comparison unit that compares analog signals to the reference signal and ends the comparison process at a timing at which the reference signal satisfies a predetermined condition with respect to the analog signals; a clock generation unit; a latch unit that retains the low-order phase signal as a latch signal at a timing related to the end of the comparison process; a count unit that counts a signal related to one of the low-order phase signals and generates a high-order digital signal; a detection unit that generates a low-order digital signal by sequentially comparing logic states of a plurality of bits of the latch signal retained by the corresponding latch unit and encoding the latch signal; and an arithmetic unit that performs an arithmetic process.