Image forming apparatus using mask original form

Abstract

An image forming apparatus capable of forming an image on a photosensitive recording medium employs a plurality of mask members for exposure prepared on the basis of image data representing the image. The mask members are to be registered sequentially at an exposure position on the photosensitive recording medium. The image forming apparatus comprises a supporting unit for supporting the mask members, the supporting unit being transported from an initial position to a different position including the exposure position, and a moving unit for moving the supporting unit to position the mask member in the exposure position, while the supporting unit is being transported from the initial position to the selected position including the exposure position. An exposure unit exposes the photosensitive recording medium through the mask member positioned in the exposure position. The image forming apparatus provides a returning unit for returning the supporting unit from the exposure position to the initial position, after exposure has been completed by the exposure unit, and a discharging unit for discharging the mask member from the exposure position to a discharging position, after exposure has been completed by the exposure unit. A controlling unit controls the discharging unit and the returning unit so that the mask member is discharged from the exposure position to the discharging position before the supporting unit begins to be returned to the initial position by the returning unit.