Image capturing apparatus, control method thereof, and storage medium

A method of controlling an image capturing apparatus including:

• a pixel portion in which pixels each including a photoelectric conversion elements that are four photoelectric conversion elements are arranged in a matrix;
• first and second sample-hold circuits that are two sample-hold circuits arranged with respect to pixel signals output from one pixel;
• a voltage-current conversion circuit configured to output a difference between the first and second sample-hold circuits, as a current signal;
• and an AD converter configured to convert an output signal of the voltage-current conversion circuit to a digital signal, the method comprising:
• performing control such that, a first pixel signal obtained from the first photoelectric conversion element is held in the second sample-hold circuit and is AD converted as a first digital signal, in a first period, the first pixel signal and a second pixel signal that is obtained from the second photoelectric conversion element are held in the second sample-hold circuit and the held signal is AD converted as a second digital signal, in a second period, and the first pixel signal, the second pixel signal and a third pixel signal that is obtained from the third photoelectric conversion element are held in the second sample-hold circuit and the held signal is AD converted as a third digital signal, in a third period,
• wherein the controller subtracts the first digital signal from the second digital signal and subtracts the second digital signal from the third digital signal.

A non-transitory computer-readable storage medium that stores a program for causing a computer to execute a method of controlling an image capturing apparatus including:

• a pixel portion in which pixels each including a photoelectric conversion elements that are four photoelectric conversion elements are arranged in a matrix;
• first and second sample-hold circuits that are two sample-hold circuits arranged with respect to pixel signals output from one pixel;
• a voltage-current conversion circuit configured to output a difference between the first and second sample-hold circuits, as a current signal;
• and an AD converter configured to convert an output signal of the voltage-current conversion circuit to a digital signal, the method comprising:
• performing control such that, a first pixel signal obtained from the first photoelectric conversion element is held in the second sample-hold circuit and is AD converted as a first digital signal, in a first period, the first pixel signal and a second pixel signal that is obtained from the second photoelectric conversion element are held in the second sample-hold circuit and the held signal is AD converted as a second digital signal, in a second period, and the first pixel signal, the second pixel signal and a third pixel signal that is obtained from the third photoelectric conversion element are held in the second sample-hold circuit and the held signal is AD converted as a third digital signal, in a third period,
• wherein the controller subtracts the first digital signal from the second digital signal and subtracts the second digital signal from the third digital signal.