| 摘要 |
PROBLEM TO BE SOLVED: To provide a portable information terminal which enables infrared communication, even when battery residual quantity is decreased. SOLUTION: When battery residual quantity detected by a battery residual quantity detecting part 4 is larger than threshold, an information controlling part 1 controls a drive current control part 3 in such the manner that the drive current control part 3 supplies a 1st drive current to a light-emitting element of an infrared communication functioning part 2. Also, when the battery residual quantity is the threshold or lower, the part 1 controls the part 3 in such a manner that a 2nd drive current that is smaller than the 1st drive current is supplied to the light-emitting element of the part 2. In this way, when battery residual quantity is low, infrared communication is made possible by making the infrared arrival distance short. Also, when the infrared arrival distance becomes short, the decrease in convenience is prevented by signaling the effect to a user from an outputting part 8. |
