The Print engine
It’stie print engine thatforms the actual charactersandgraphics. The
enginedirectsitslaser,apinpointstreamoflightpulses,throughmirrorsand
lensesontothe surface ofapositively-chargedrotatingdrum.
r“’””’
Lens
Laser beam
Scanning mirror
uctor laser diode
Photosensitive drum
Asthelaserscans,it “draws”thepage-mapstoredinyourprinter’smemory.
Whereveralightpulsestrikes,that tinypartof thedrumdrops toaneutral
electricalcharge.That spot then attracts finetoner powder as the drum
rotatespastthe powdercompartment.
Asthedrum rotatesfurtheritmeetsthepaper.Thepaper itselfisnegatively
chargedbypassingbyafinecoronawire.Sinceoppositechargesattract,the
negativepaperclingsto the positivedrum.Thenheat andpressurefrom a
rollermeltorjkre thedotsof tonerontothepaper,preciselyreproducingthe
image.
Finallythepaperslidesintotheoutputbin.Thepaperusuallycomesoutface
downso it stacksin the correctsequence.
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