Patent ID: 8774679

Claim:
An electrographic printing system for forming a tactile printed image on a receiver medium, comprising: an image processing path that provides a sequence of image patterns including a plurality of annular shapes having associated inner and outer sizes, the inner and outer sizes of the annular shapes varying in a monotonic sequence; one or more printing modules including: an image forming system adapted to form an electrostatic latent image on a primary imaging member according to a supplied image pattern; a development subsystem adapted to form a toner particle image on the primary imaging member by depositing charged toner particles in accordance with the electrostatic latent image; and a transfer subsystem adapted to transfer the toner particle image to the receiver medium; a fixing subsystem adapted to permanently attach the transferred toner particle images to the receiver medium; and a controller system adapted to: control the one or more printing modules to form a sequence of toner particle images corresponding to the sequence of image patterns, and to sequentially transfer the sequence of toner particle images in register onto the receiver medium such that the annular shapes in the toner particle images overlap to form a tactile image feature having a hollow core; and control the fixing subsystem to permanently attach the transferred toner particle images to the receiver medium.