Patent ID: 9602751
Date: 2017-03-21
CPC Classifications: H04N

Claim:
1. An imaging apparatus comprising: a photoelectric conversion unit configured to generate an electric charge by photoelectric conversion; a selecting circuit configured to select a reference signal, according to a level of a signal based on the electric charge, from a plurality of reference signals including a first reference signal having a first time-changing ratio and a second reference signal having a second time-changing ratio larger than the first time-changing ratio; a comparator configured to perform a first comparison operation of comparing a base signal and the first reference signal, and configured to perform a second comparison operation of comparing a signal based on the electric charge and the first or second reference signal output from the selecting circuit; a counter configured to count a first count value until an inversion of a magnitude relation in the first comparison operation, and configured to count a second count value until an inversion of a magnitude relation in the second comparison operation; and a correcting unit configured to perform a correction of at least one of the first and second count values, so as to reduce a difference between a resolution of the first count value and a resolution of the second count value, when the second comparison operation is performed by comparing the signal based on the electric charge and the second reference signal.