A lens frame holding a taking lens is movably connected to a driving shaft via a connector. A guide member is disposed at a lower portion of the lens frame so as to separate from the connector by about 180 degrees around an optical axis. The guide member is movably attached to a guide rod. A light emitter is disposed on a lateral side of the lens frame so as to separate from the connector by about 90 degrees around the optical axis. The light emitter applies the light to a light receiver of a line sensor confronting the light emitter. The line sensor sends a light-reception signal, which is outputted from the light receiver, to a lens-position controller. Positional information of the taking lens is obtained on the basis of the light-reception signal so that a position of the taking lens is accurately detected.