A sensor panel is overlaid on a display apparatus and connected to an integrated circuit that detects a position of an active pen in an active region of the display apparatus. The sensor panel includes first electrodes that extend in a first direction. The sensor panel also includes second electrodes that extend in a second direction. The first electrodes include first and second outer electrodes that are located at the outermost edges of the first electrodes and first inner electrodes disposed between the first and second outer electrodes. A width of at least one of the first and second outer electrodes in the second direction is smaller than a width of each of the first inner electrodes in the second direction.