A cellular telephone handset has a built-in image pickup device. A lid shaped reception unit is slidable on a transmission unit or main body between closed and open positions, lies on a first surface of the main body when in the closed position, and uncovers at least part of the first surface when in the open position. An image sensor to pick up an image is contained in the main body. A first lens element receives object light incident thereon. Plural second lens elements in the main body have an optical axis extending in a sliding direction of the lid shaped reception unit, for introducing the object light to the image sensor. A path bending prism introduces the object light to the second lens elements by changing an optical path of the object light from the first lens element. An optical path length of the second lens elements is changeable.