Importance

Loading Importance Indicators...

Abstract

A digital data imaging system in which the duration of each exposure pulse of a laser beam is directly locked to the speed of movement of the film. Thus the area of the film exposed during each pixel is independent of the speed of rotation of the drum. If the drum speed decreases, the exposure time is automatically increased. The rotating drum is provided with a conventional rotary encoder that produces a fixed number of signal pulses per revolution. These primary pulses are multiplied by conventional phase-locked loop technology to produce a large number of clock pulses. The duration of each clock pulse represents a fixed increment of movement of the surface of the drum that is independent of the rotational speed of the drum. These clock pulses control the timing and on-off ratio of the laser exposure pulses. By locking the timing of the laser beam exposures (equivalent to the shutter speeds in a camera) to the rotary encoder, even slight variations in the drum speed, whether caused by system factors or operator induced, appropriately change the pixel timing.

Loading the Abstract Image...

First Claim