To expand the usage of a personal digital assistant with a camera function by changing an optical characteristic of a camera in the personal digital assistant with a camera function.

A lens 16A and an imaging device 16E for receiving light from a far point side object point image-formed by the lens 16A and outputting a corresponding image pickup signal are arranged on a housing 10, and a cover member 12 where an adapter optical system 26 is disposed at a prescribed position is coupled to the housing 10 so as to be relatively displaceable with housing 10 between prescribed positions including a position at which an optical axis of the lens 16A almost coincides with an optical axis of the adapter optical system 26. In such a case, when the optical axis of the lens 16A is made to almost coincide with the optical axis of the adapter optical system 26, a synthetic optical system composed of the lens 16A and the adapter optical system 26 has an optical characteristic suitable to image-form light from a near point side object point on the imaging device 16E, and a LED 34 for illumination for illuminating the near point side object point is disposed at the cover member 12.