Print Enhancement for Laser Printers
Original Publication Date: 1986-Aug-01
Included in the Prior Art Database: 2005-Mar-09
A control algorithm enables a given picture element (pel) to be printed with one of the four shades, white, grey, dark grey or black, dependent upon analysis of 24 pel areas surrounding the given pel area. A laser is used to selectively discharge a xerographic photoconductor in order to produce the required shade of toner deposit on the given pel area. The control algorithm operates to define one of four possible two-bit words, which words in turn produce one of these four possible shades within the pel area. These four words and the shades defined by the words are: "00" = white "01" = grey "10" = dark grey "11" = black In Figs. 1 through 8, the given pel area 100 is at the center of a five-by-five pel matrix.