| 摘要 |
Provided is a laser beam optical scanner apparatus as a component in a system for the scanning of an original and the simultaneous exposure of a light sensitive surface of a printing master with the image of the original for the production of a printing plate. Said apparatus comprises rotating reflective means having at least one planar reflective segment. Said segment defines a tilt angle which is off normal to the axis of rotation of said rotative, reflective means. The system further comprises means for rotating said reflective means about its axis of rotation; means for supporting said reflective means at a position interposed in the common path of a read and write laser beam for deflecting said laser beam into a roof mirror arrangement and for receiving the same beam reflected out of said roof mirror arrangement, to scan a line at an output plane in space. Said roof mirror arrangement includes a first mirror with a first planar reflective surface and a second mirror with a second planar reflective surface. Said first and second mirrors are disposed in fixed positions relative to each other and to the rotating reflective means. Said laser beams are reflected 2n times between said first and said second mirrors and 4n times in said rotating reflective means before the laser beams emerge the optical scanner apparatus, where n is any integer. |
