Solid-state imaging element, range imaging device, and control method

A method of controlling a solid-state imaging element, the solid-state imaging element including a plurality of pixels each of which includes a photoelectric conversion device, charge storage circuitry, and a reset switch and including addition switches that are connected in series in two or more stages and each of which is disposed between the power supply line and a connection line connecting power supply line sides of the reset switches of a predetermined number of pixels of the plurality of pixels, the method comprising:

• generating, by the photoelectric conversion device, charge corresponding to incident light;
• storing the charge by the charge storage circuitry;
• resetting a potential of the charge storage circuitry to a predetermined reset potential supplied from a power supply line;
• changing a conduction state of the reset switches and the addition switches;
• and
• changing, by said changing the conduction state, a region of the pixels in which addition of the charge stored in the charge storage circuitry is performed.