Methods and arrangements to methods and arrangements to attenuate electrostatic discharges of a cable are disclosed. For a pixel with coordinates of the image I, a convolution is done with a core U equivalent to a low-pass filter whose coefficients have been modified as a function of the neighborhood of the pixel with coordinates in the image I. Mutually facing surfaces of the display window member and the rotation operation portion are provided with grooves that have substantially the same diameter as the ring member.