Display apparatus and portable information processing apparatus

摘要

A display apparatus has a display unit for displaying, on a display screen, a display image containing a time axis formed so as to extend at least in a first direction. The display apparatus also has an input operation device for physically moving at least the time axis in the first direction. The display apparatus further has a controlling device for controlling the display screen based on an operational input given by an operation of the input operation device. The input operation device includes a rotational operating unit having an axis of rotation extending in second directions which cross the first direction. The rotational operating unit is arranged such that a rotational operation of the rotational operation unit by a first physical amount causes a physical movement of at least the time axis by a second physical amount corresponding to the first physical amount.