5-4
Phaser 480 Color Printer
5
Theory of Operation
Continuous-tone printing
The dye sublimation process can overlay precise amounts of dye onto each
printer dot with much more precision than its cousin, the thermal-wax printer.
Consequently, each dot is the exact color it should be, not an approximation.
This results in what is called continuous-tone printing. Where thermal-wax
printers must simulate a color by arranging a matrix of cyan, magenta, and
yellow dots together in a specific pattern called a halftone to trick the eye into
seeing an intermediate color, the dye sublimation printer can print that actual
color with a single dot. Because no dithering is used and the printer can create
continuous-tone colors, the printer can output photorealistic output.
Image data
The print engine must receive data in a specific format in order to correctly print
the image the data represents. The printer's image processor board must convert
the data into the correct format. The following topics describe some of the data
formatting that the host or the interface module must perform.
Figure 5-2. The dye sublimation print process
8850-12
IMAGE
IMAGE
Supply spool
Mylar film
impregnated
with bands of
colored dye
Take up spool
Thermal head
Paper
Platen
