PORTABLE INFORMATION TERMINAL DEVICE HAVING ILLUMINATION CONTROLLING FUNCTION

摘要

PROBLEM TO BE SOLVED: To provide a portable information terminal with which a position of a light-receiving element for measuring surrounding illuminance is not restricted and precise illuminance control can be achieved for a display unit for displaying data and an operation unit for inputting an operation. SOLUTION: While a light for illuminating a display unit and an operation unit and a light for displaying a received message are on, appropriate correction is performed for a measured value of surrounding illuminance. By using the determined value after correction, illumination of the display unit and the operation unit mounted on a portable information terminal device is controlled.