In order to improve the quality of text and graphic printers, companies have increased the resolution of the imaging subsystem and decreased the diameter of toner particles in electrophotographic powder marking technologies. We have been developing a new electrographic printing technology in which the latent image is formed by contacting a write head with many metal fingers to square metal pads on 50 μm centers (500 dpi) fabricated on an insulating cylinder. This system has demonstrated the ability to print for the first time, to our knowledge, in any powder marking system, both black and white single pixels at 500 dpi, using normal 9 μm diameter toner. A theoretical explanation for this result is given.
G. Bartscher, F. Morgenweck, K.-U. Preissig, D. Rohde, S. O. Cormier, D. Kostyk, R. Lyness, G. Hauptmann, L. B. Schein, "Single Pixel Development in a New Electrographic Printing System" in Journal of Imaging Science and Technology, 2001, pp 523 - 528, https://doi.org/10.2352/J.ImagingSci.Technol.2001.45.6.art00004