Imaging apparatus and method of driving the same

摘要

An imaging apparatus and a method of driving the same that can generate a digital data of a high resolution pixel signal are provided. The imaging apparatus includes: a pixel (10-1) for generating a signal by photoelectric conversion; a comparing circuit (30-1) for comparing a signal based on the pixel with a time-dependent reference signal; a counter circuit (40-1) performing a counting operating until an inversion of a magnitude relation between the signal based on the pixel and the time-dependent reference signal; and a selecting circuit (30-2) for setting a time-dependent change rate of the reference signal, according to a signal level of the signal based on the pixel.

主权项

1. An imaging apparatus, comprising:
a plurality of photoelectric conversion units each configured to generate a charge based on photoelectric conversion; a plurality of comparing circuits each configured to output a first comparing result signal by performing a first comparison comparing a noise signal with a reference signal having a first time-changing rate, a second comparing result signal by performing a second comparison comparing a signal based on the charge with a reference signal having the first time-changing rate or a reference signal having a second time-changing rate larger than the first-time changing rate, a third comparison result signal by performing a third comparison before the second comparison comparing the signal based on the charge with a threshold value; and a counter circuit configured to generate a count value by performing a counting operation, wherein the second comparison is performed by using the reference signal (1) having a voltage changing in the first time-changing rate in a case that the third comparing result signal indicates that the signal based on the charge is smaller than the threshold value, and (2) having a voltage changing in the second time-changing rate in a case that the third comparing result signal indicates that the signal based on the charge is larger than the threshold value, and the count value at a time of changing a signal level of the first comparing result signal is outputted as a digital signal based on the noise signal, while the count value at a time of changing a signal level of the second comparing result signal is outputted as a digital signal based on the signal based on the charge.