Abstract: A laser beam printer using a film, in which a fixed form of format information such as a ruled line is printed off, and having a format overlay function is disclosed in which a photosensitive drum is line-scanned by a laser beam having been modulated in accordance with print information and having passed through the film, the film is moved in synchronism with the rotation of the photosensitive drum, and thus a latent image is formed on the photosensitive drum in a manner that the format information in the film is superposed on the print information for modulating the laser beam.

Abstract: A control system for controlling a laser beam printer in which a light-sensitive drum surface is scanned on a line base with a laser beam modulated in accordance with data to be printed. The width of scanning lines is broadened so that the adjacent scanning lines are partially superposed each other at those portions where both of the adjacent lines are to be irradiated with the laser light beam, while at those portions where at least one of the adjacent lines are not to be irradiated, the scanning line is reduced in width.

Abstract: A laser beam printer in which latent images are produced on a light-sensitive drum through line scanning with a laser beam modulated with print information to be printed. The laser beam is modulated with the information to be printed in such a manner that the light sensitive drum is irradiated with the laser beam except for those portions which are to be printed. The line scanning is effected with the laser beam modulated in accordance with the print information in a non-superposed manner on one hand and on the other hand with the laser beam which is modulated by information synthesized from the printing information for every two adjacent line scanning so that these two adjacent line scannings are partially covered by the line scanning based on the synthesized information.