Drum scanner with laser exposure unit

摘要

The scanner includes an optical prism (8) in the path of the beam (1) to the single or double mirror (2) and the prism possesses an incident surface (9) and another surface (10) at an acute angle to the optical axis (12a), correcting the errors of the mirror surface (2a) at the incident point (7a) on the film (6) and its cylindrical form, concentric with the axis of rotation, as the mirror drum is rotated by the motor (4a).