| 摘要 |
A laser recording system is disclosed in which a beam of light from a laser is split into first and second beams. The first beam is modulated with digital signals from a computer and deflected by a rotating mirror onto the surface of a photoconductive drum. The second beam is deflected by the rotating mirror onto a curved timing plate. The surface of the timing plate is provided with a series of unevenly spaced reflective markings representative of evenly spaced spot positions on the surface of the drum. Light reflected by the timing plate as the second beam scans its surface and strikes the reflective markings impinges on a photodetector located at the center of curvature of the timing plate and is converted by the photodetector into a corresponding series of electrical signals. The electrical signals are converted into pulses which are used to gate the flow of digital signals from the computer so that the light spots formed on the drum by the first beam are evenly spaced and not effected in their placement by the changing angular velocity of the first beam as it is swept across the drum.
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