The contact point is a point on which the user's ear and the speaker part 9 of the mobile phone are contact. [0105] A center position Pb of the eyepiece lens part of the display eyepiece part 6 a (3 b) is determined as follows. [0106] A center position Pb of the eyepiece lens part of the display eyepiece part 6 a which is ergonomically easy to watch an image is positioned in a direction that an op