To specify an effective illuminance detection part from an inclined state of a mobile phone 10 so that the peripheral brightness can be appropriately detected and thereby, controlling brightness of a display 14 appropriately.

A mobile phone 10 comprises a display 14 arranged in a housing 12, and such. On a front face of the housing 12, a window 24 communicating with an illuminance sensor (56) is arranged, and on a rear face of the housing 12, a lens aperture 26 communicating with a camera module (52) is arranged, Also, as the camera module and the illuminance sensor can detect the brightness respectively, each of them function as an illuminance detection part. Further, an inclined state of the mobile terminal 10 is detected by an acceleration sensor (54) arranged inside the housing 12. For example, when a power source of the display 14 is turned on, an effective illumination detection part is specified on the basis of the inclined state. Then, the brightness of the display 14 is controlled on the basis of the brightness detected by the specified illumination detection part.