Display device with built-in touch panel and method for controlling display device with built-in touch panel

Provided are a touch panel provided with an electrophoretic display unit capable of detecting touch coordinates of a plurality of points, and a method for controlling the touch panel. A touch panel (1) is provided with: a plurality of detection electrode pairs (41, 42) arranged side by side in the Y direction; and a touch coordinate detection circuit (2b). A touch coordinate detection circuit (2b) supplies a voltage to a plurality of detection electrode pairs (41, 42), acquires detection values that are potentials of the detection electrodes (41, 42), determines the presence or absence of a touch at a Y-coordinate in which the detection electrode pairs (41, 42) are disposed on the basis of the sum of the detection values of the detection electrode pairs (41, 42), and when it is determined that a touch is present, determines the presence or absence of a touch on the basis of the detection electrode pair (41, 42) determined that a touch is present. The X-coordinate of the touch performed by the pointing body is