Solid-state imaging apparatus

Abstract

A solid-state imaging apparatus comprises a plurality of matrix pixels, a reference signal generator for generating a ramp signal, a counter for performing counting according to the ramp signal output, and an AD converter, arranged for each pixel column, for performing AD conversion by comparing a pixel signal from the pixel with the ramp signal. Further, the AD converter includes a comparator to which the pixel signal and the reference signal are input, a storage for storing the AD conversion result, and an slope converter, between the output terminal of the reference signal generator and the input terminal of the comparator, for changing a gradient of the ramp signal, so that the noise overlaid on the ramp signal changes depending on the gradient of the ramp signal. Thus, it is possible to prevent generation of a horizontal-line noise in the ramp signal.

1 . A solid-state imaging apparatus comprising:
 a plurality of pixels arranged in a matrix, each of the plurality of pixels including a photoelectric conversion element;   a reference signal generating circuit configured to generate a reference signal of which a signal level changes with the passage of time;   a counter circuit configured to perform a counting operation according to the change of the reference signal; and   an AD converting circuit, arranged for each column of the pixels, configured to perform analog-to-digital conversion to a pixel signal transferred from the pixel by comparing the pixel signal with the reference signal,   wherein the AD converting circuit includes   a comparator having a first input terminal to which the pixel signal is input and a second input terminal to which the reference signal is input,   a storing unit configured to store a count value of the counter circuit when an output of the comparator is inverted, and   an slope converting circuit including a first capacitor connected between an output terminal of the reference signal generating circuit and the second input terminal of the comparator, and a second capacitor connected between the second input terminal of the comparator and a reference voltage.   
     
     
         2 - 8 . (canceled)