| 摘要 |
PROBLEM TO BE SOLVED: To obtain a mobile phone provided with a man-machine interface providing excellent operability. SOLUTION: A thumb of a user comes to a position of a pushbutton on a front side and an index finger of the user comes to a position of a track ball 103 on a rear side when the user grips the mobile phone very naturally. Thus, the user uses the thumb to operate the pushbutton on the front side and also uses the index finger to operate the track ball on the rear side while viewing a liquid crystal display device 101 on the front side. |
