Table of Contents
Advertisement
Whentextor graphicsare sentby the computerto the printer,laser beamis
generatedby a semiconductor l aser diode.Thisbeam is focusedby special
scanningmirrorsthatturnthelightbeamintoa toolthat"writes"or''pnnts"
on the surfaceof the drum.The areasof the drumtouchedby thelaserbeam
lose their negativecharge and containa reverseimage of the information
sentfrom the computer.As the drumrotates,it passesa developerunitthat
is also rotating,but in the oppositedirection.The surfaceof the developer
unit is covered with toner ("ink") which has a negative charge. The
neutralizedportionsof the drum,containingthe informationto be printed,
pick up negativelychargestoner from the developerunit.
At this point,paperfed fromthe papercassettemovesthroughthe transfer
unit, from which it receives a positive charge. As the drum rotates, the
negativelychargedparticlesof tonerare attractedto thepositivelycharged
surfaceof the paper.
A combinationof heat andpressurefuse the imageto the paper.The paper
is then ejectedfrom the printer.
Finally, a cleaningmechanismin the toner cartridgecleans excess toner
tlom the drum, and a speciallightbeamneutralizesits entiresurface.Then
the entireprocesscan begin again.
3
Advertisement
Table of Contents
