Lauren Martin Rust

US Patent:

53749456, Dec 20, 1994

Filed:

Jan 4, 1993

Appl. No.:

8/000540

Inventors:

Eduardo M. Molieri - Mesa AZ
Nancy R. Robins - Mesa AZ
Lauren M. Rust - Chandler AZ

Assignee:

Motorola, Inc. - Schaumburg IL

International Classification:

B41J 232

US Classification:

346 76PH

Abstract:

A method for gray level printing using a thermal printhead which includes characterizing the paper to be printed, defining a line of a gray scale image using bitplane data sets, entering the first of the bitplane data sets into a shift register, transferring the first of the bitplane data sets from the shift register to a latch, beginning to print a section of the line of the gray scale image using the first of the bitplane data sets in the latch, entering consecutively the remaining bitplane data sets in the shift register, transferring consecutively the remaining bitplane data sets to the latch, and completing the printing of the section of the line of the gray scale image. Multiple refreshing of data per segment printing enables less than 10 millisecond line (1728 bit) printing in 16 shade gray scale.