Patent ID: 7800778

Claim:
An apparatus for exposing, in a binary manner, a photoreceptive surface having a width and having relative movement with an irradiator in a direction perpendicular to the width, comprising: an irradiator comprising substantially identical light sources organized in a plurality of rows and a plurality of columns, each said row of light sources having an axis generally directed along said width, said rows being spaced in a direction generally perpendicular to said width and along the columns to form a generally rectangular array of light sources, where the light sources are organized in groups of light sources that are each one light source in height and a plurality of light sources in width, a single light source group being positioned in each row; and a controller that controls activation of the light sources to selectively irradiate portions of said photoreceptive surface to form a latent image thereon during said relative motion, using fewer than all of the light sources available for illuminating each pixel to be printed; wherein the controller controls the light sources such that each of said pixels to be printed that is irradiated is exposed to a same amount of light, wherein to minimize visibility of anomalies within the light sources, the controller is to: randomly select, for a line of pixels to be printed, the groups of light sources to print the line of pixels; and, one of: select, for sequential rows of pixels to be printed, different groups of light sources to print the sequential rows of pixels; or, randomly select, for each pixel within a row of pixels to be printed, the light source to print the pixel from all the light sources within the light source groups of a column corresponding to the pixel, wherein the light sources are anomalous in that the light sources lack uniformity.