Epson DFX-8000 User Manual

The print head

The print head
To urtderstand dot graphics you need to know a little ‘about ‘how
your printer's print head works.
As the print head moves  across the page,  electrical impulses cause
the pins to fire. Each  ‘time a pm fires, it strikes the inked ribbon
and presses it against the paper to produce a small dot. As the head
moves across the page, the pins fire time after time in different
patterns to produce letters, 
 or symbols.
Dot patterns
The DFX’s print head is able to print graphics as well as text
because graphic images are formed on the printer about the same
way that pictures in newspapers and magazines are printed. If you
look closely at a newspaper photograph, you can see that it is made
up of many small 
patterns of dots, 
many as 240 dot positions per inch horizontally
and 72 dots vertically. The images printed by the printer can,
therefore, be as finely detailed 
as the one on 
page 4-10.
for each code it receives, and it uses only the top eight of the nine
pins. Therefore,. your 
 send codes for dot
patterns, one 
 in a line. 
columns, the print 
 of dots 
To print figures taller than eight dots, the print head makes more
than one pass, The printer prints one line, then advances the paper
and prints another, 
 as it does with text.
To keep the print head from leaving 
 the graphics lines
as it does between the text lines, 
 spacing must be changed
to eliminate the 
 in line spacing,
your printer can print finely detailed graphic images that give no
indication that they are made of separate lines, 
 no more than
8/72nds of an inch tall.
Software and Graphics 4-11