Scanner with a linearized pixel clock

Abstract

A scanner system includes a light source for producing a light beam and a director that directs the light beam to a spot on a surface to be scanned moving the spot across the surface along a scan line of predetermined length in a series of scan cycles. The scanner system has a pixel clock for producing a train of clock pulses during each of the scan cycles configured so that some of the clock pulses are spaced apart by a first time interval and others are spaced apart by a longer second time interval in order to maintain timing of the clock pulses according to spot position along the scan line in a manner that compensates for scanner non-linearity in order to reduce pixel position distortion. The pixel clock includes a reference clock for producing a train of reference pulses having a period such that at least M reference pulses occur during the time the spot moves from a first end of the scan line to a point along the scan line that is a distance from the first end of the scan line equal to L/N, where L is the length of the scan line, M is a predetermined integer, and N is a predetermined integral number of pixel positions along the scan line. The first time interval represents the occurrence of M reference pulses and the second time interval represents the occurrence of M+I reference pulses, where I is an integer.