Transcript presentation source

4/19 Inkjet Printers.
• Roll call
• Video (10 seconds)
• Lecture:
– inkjet printers
Inkjet Printers: the parts
• Paper feeder & tray
• The print head
• The ink cartridge(s)
Inkjet Printers: the parts
• Paper feeder & tray
• The print head
• The ink cartridge(s)
Image courtesy of http://www.hp.com
Inkjet Printers: the parts
• Paper feeder & tray
• The print head
• The ink cartridge(s)
Image courtesy of http://www.hp.com
Inkjet Printers: the parts
• Paper feeder & tray
• The print head
• The ink cartridge(s)
– ink reservoir
– nozzles
– circuitry
Image courtesy of http://www.hp.com
The Ink Cartridge.
• The ink cartridge(s)
–
–
–
–
Cross-section of a nozzle.
nozzle
firing chamber
thin-film resistor
path from reservoir
How the ink gets out.
• 2 ways:
– Thermal method
– Epson piezo-electric
method
How the ink gets out: thermal method.
Nozzle
Firing
Chamber
Resistor
• Used by Hewlett
Packard & Canon
• A thin-film resistor is
heated by electric
current.
• The resistor heats up
the ink that is next to
it.
How the ink gets out: thermal method.
Nozzle
Firing
Chamber
Resistor
• The ink- now
gaseous - expands,
forming a bubble.
• The bubble pushes
out the rest of the ink
in the firing chamber.
How the ink gets out: thermal method.
Nozzle
Firing
Chamber
Resistor
• The resistor cools,
causing the bubble to
shrink.
• The shrinking creates
a vacuum, which
draws new ink from
the reservoir.
Or, the piezo-electric method.
Nozzle
Firing
Chamber
Piezo crystal
• Instead of a resistor
that heats up, Epson
uses a piezo crystal.
• A piezo crystal
flexes when a current
is applied.
• This pushes the ink
out.
Advantages of the piezo.
Nozzle
Firing
Chamber
Piezo crystal
• Ink doesn’t have to
be heat resistant.
• Piezo’s flex can be
controlled to put
more or less ink on
the page.