A problem of this invention is to satisfy both of securement of visibility
of a display unit and suppression of noises at the time of a telephone
call etc. using a receiver and a microphone. In a portable terminal
apparatus which relates to the invention, a control unit (16) judges
whether a handsfree device (20) is connected or not, on the occasion that
a telephone call operation is carried out by an operation unit (18) and a
voice telephone call operation by a telephone call circuit (11) and a
transmission/receiving unit (12) is started, and in case that the
handsfree device (20) is not connected, it is judged that a user is
making a telephone call by use of a receiver (13) and a microphone (14)
in an apparatus main body in such a state that he puts an apparatus
casing to his ear part, and at least one of a drive system, drive
frequency of a display unit (19) which comprises a liquid crystal display
is changed, and a drive operation giving priority over acoustic
characteristics is carried out. On one hand, in case that the handsfree
device (20) is connected, a drive operation with high picture quality
giving priority over optical characteristics of the display unit (19) is
carried out without changing the drive system etc.