Continuously variable resolution laser printer

A continuously variable resolution printer which comprises:

• an electrophotographic image recording and registration means, including a photoconducting medium, for recording an image generated by light pulses and transferring the image to a printing medium such as paper;
• input means for inputting an image of known width, control codes and user selected parameters such as vertical resolution and horizontal resolution;
• formatting means, being connected to the input means, for converting the image, control codes and user selected parameters into a data stream to be used to modulate a laser;
• laser means for emitting a modulated beam of light pulses;
• laser control means, being connected to the laser means and the formatting means, for modulating the laser at variable base frequencies and variable widths of modulating pulses to transmit the data from the formatting means;
• variable frequency generation means, being connected to the formatting means and the laser control means, for generating a clock signal to supply a base frequency for data transfer and laser modulation,
• variable speed scanner means for scanning the modulated laser beam in both vertical and horizontal directions across the photoconductive medium wherein the means for scanning the beam in the horizontal direction includes at least one rotating mirror facet;
• a control circuit being connected to the formatting means, the laser control means, the variable frequency generation means and the variable speed scanner means wherein the control circuit is configured to calculate:
• a) a paper speed, according to the equation ##EQU10## and a base frequency according to the equation ##EQU11## where this resulting base frequency is additionally multiplied by the denominator of a fraction representing any decrease in the paper speed from a maximum value,
• by first assuming that the paper speed is equal to a predetermined maximum value and then checking to see if the resulting base frequency is below any physical limitations of either the formatting means or the frequency generation means, and if not, iteratively reducing the paper speed until the resulting base frequency is within any limits dictated by the formatting means or the frequency generation means;
• b) a rotational mirror velocity according to the equation ##EQU12## and to transmit the calculated paper speed value and the calculated rotational mirror velocity value to the scanner means and to transmit the calculated base frequency value to the variable frequency generation means and the formatting means;
• the variable speed scanner means being configured to rotate the mirror facet at the calculated rotational mirror velocity and scan the laser beam in the vertical direction at the calculated paper speed velocity;
• and
• the variable frequency generation means and the formatting means being configured to modulate the laser beam at the calculated video rate.