3751587 is referenced by 42 patents and cites 4 patents.

A modulated laser beam developed in a non-contacting printing arrangement sweeps across an ink bearing carrier disposed adjacent a printing surface, e.g., an untreated paper sheet. In successive line sweeps, each slightly displaced from the prior sweep line, the incident laser beam selectively transfers printing materials, such as ink, from the carrier to the paper surface in accordance with the laser modulation intelligence. The modulator reduces or shutters the laser beam in such manner as to prevent ink transfer where printing is not desired and allows the laser beam to pass or directs the laser beam to points where printing is desired. Printing speed for the composite printing system directly depends upon the rate at which ink can be displaced from its carrier, and therefore ultimately upon laser power. In a copying machine context, the laser modulating information is developed by scanning the original document to be reproduced.In accordance with the present invention, the laser beam is alternately accelerated and slowed with respect to the average sweep rate across the ink bearing carrier during printing to essentially dwell at such points on the carrier where it is desired that ink be displaced onto the printing surface during the sweep of a line trace. Accordingly, the power of the laser beam required to transfer ink is reduced, and thereby also permissible printing speeds are increased, by reason of the swell of the laser beam on the ink vis-a-vis that situation where the laser beam is swept at a constant speed acros the ink bearing carrier.

Laser printing system
Application Number
Publication Number
Application Date
January 20, 1972
Publication Date
August 7, 1973
Vigneri Ronald J
Leslie Allen R
Insler Julius R
H04n 01/10
H04N 01/113
H04N 01/17
G06K 15/12
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