3.11 Printer Flashcards
Laser Printer
• Combine a laser, high voltage, charged ions,
powdered ink, heat, and paper
• Very high quality
• Fast printing speeds
• Very complex, many moving parts, requires on-printer
memory and messy on the inside
Laser Printer: Imaging drum
- Image is drawn onto a photosensitive drum
- “Painted” with a laser
- Picks up toner - Transfers toner to the paper
- Can be separate from the toner cartridge or combined
Laser Printer: Fuser assembly
- Heat and pressure - Melt plastic toner powder
* Permanently bond toner to paper
Laser Printer: Transfer Belt and Roller
- Color laser printers
- Cyan, yellow, magenta, black
- Four separate toner cartridges
- Image is transferred from all cartridges to the single belt
- And then to a single transfer roller
Laser Printer: Pickup Rollers
• Pickup paper - Should be a single page at a time
• Problems if no paper is picked up
or multiple sheets are picked
• Should be periodically cleaned or replaced
Laser Printer: Separation Pad
- Pull just the top sheet from the paper tray
- Not multiple sheets
- Small and inexpensive - Easy to clean or replace
Laser Printer: Duplexing Assembly
- Printers usually print on a single side
- Not both sides simultaneously
- Printing on both sides is a two step process
- Print side one, print side two
- You need mechanisms to “flip” the page
- Automatically
- Can be built-in to the printer
- Or available as an add-on
Laser Printer: Processing Step 1 - 7
Step 1: Processing • Build the entire page in memory Step 2: Charging • Prepare the drum with a negative electrostatic charge Step 3: Exposing • Write the image with the laser Step 4: Developing • Add toner to the charged areas of the imaging drum Step 5: Transferring • Move the toner from the drum to the paper Step 6: Fusing • Heat and pressure Step 7: Cleaning • Remove excess toner
Laser Printer Maintenance: Replacing the Toner Cartridge
- Look for the messages
- Low doesn’t mean empty
- The toner can also contain the OPC drum
- Organic Photoconductor drum
- Sensitive to light; keep it in the bag
- Power down the printer
- Safety first
- Remove packing strips from the new drum
- Replace it with the old
Laser Printer Maintenance kit
- Laser printers wear out
- All those moving parts
- Heat and pressure
- Standard maintenance kits
- Replacement feed rollers, new fuser unit, etc.
- When to perform maintenance?
- Check the printer’s page counter
- Power down and replace the components
- Fuser units are HOT
- Reset the page counter when you’re done!
Laser Printer Maintenance: Calibration
- Different toner cartridges print with different densities
- Some dark, some light
- Laser printer calibration can adjust the density
- Makes it looks perfect
- Can be automated or a manual process
- Every printer is different
- Check the printer manual
Laser Printer Maintenance: Laser Printer Cleaning
- Laser printers are dirty - All that toner and paper dust
- Check the manufacturer’s recommendations
- Water, isopropyl alcohol (IPA)
- Don’t use harsh chemicals!
- Outside - Damp cloth
- Inside - Wipe dust away
- Don’t use a normal vacuum cleaner or compressed air
- Wash off skin with cold water
- Clean rollers with IPA
Inkjet Printers: Inkject(ink-dispersion) printer
- Relatively inexpensive technology
- Quiet
- High-resolution
- Expensive ink
- Proprietary
- Eventually fades
- Clogs easily
Inkject Printer: Ink Cartridge
- Place drops of ink onto a page
- Pulled from a set of cartridges
- CMYK
- Cyan, Magenta, Yellow, Key (black)
Inkject Printer: Print head
• Some consumer printers integrate the print head into
the ink cartridge
• Change the cartridge, get a new print head
• Others separate the ink cartridge from the print head
