A light beam modulated with image information is outputted from a light source and supplied to a switcher, which guides the light beam to one of exposure heads that is selected by the switcher. The light beam is applied from the selected exposure head to a photosensitive medium that is mounted on a partly cylindrical inner circumferential surface of a support to record an image thereon. The light beam can continuously be applied to the photosensitive medium from the exposure heads that are alternatively selected as facing the photosensitive medium, so that the image can efficiently be recorded on the photosensitive medium.