Lesson 11 - Chapter 2: The Laser Printing Process Flashcards
What are the 7 steps in the laser printer imaging process?
- Processing
- Charging
- Exposing
- Developing
- Transferring
- Fusing
- Cleaning
Where does the CPU send your print job request to?
an area of memory called the print spooler
What does the print spooler do?
Allows you to queue up multiple print jobs sequentially (the memory that holds the print job queue)
What does it mean when the printer icon in the notification area at the bottom of the screen goes away?
It means the print queue is empty, all jobs have gone to the printer
What are 2 potential bottlenecks when it comes to the print spooler?
- When Windows sends the first print job to the printer
- Printer receives some or all of the job and the printer hardware takes over
What’s the difference between Impact printers and Laser printers when transferring data to the printer?
Impact = one character/line at a time
Laser = entire pages at a time
What is a raster image?
a pattern of dots that a laser printer paints on the drum to represent what the final image should look like
What’s another name for laser printers? Why are they called that?
page printers, because it processes images one page at a time
(drum needs to have the entire surface painted before transferring to paper)
What does RIP stand for?
Raster Image Processor (chip)
What does the RIP chip do?
it gives instructions to the laser on how to translate images into raster images
(needs RAM to store data to be processed)
What printers use RIPs? What’s the difference?
Inkjets and Laser Printers
(For inkjets, they’re written into the device drivers not the onboard programming)
A laser printer must have enough ____ to process an entire page
memory
What error do you get when there’s insufficient memory to process the image?
Memory Overflow error (MEM OVERFLOW)
What are 3 things you can try if you get a memory overflow error?
- Reducing the resolution (high resolution = more memory)
- Printing smaller graphics
- Turning off RET (Resolution Enhancement Technology)
What’s the best solution to a memory overflow error?
Add more RAM to the laser printer
Adding more RAM chips will solve almost every printer error that contains memory. T or F?
False, sometimes the data is too complex for the RIP and you would have to reduce fonts, formatting, resolution, etc to make it less complex
The 2 common laser printer resolutions are…?
600 x 600 dpi
1200 x 1200 dpi
In laser printer resolutions, which number is the horizontal resolution? What is it determined by? (2)
- The first number (600 x 600 dpi)
- Determined by how fine a focus the laser can achieve
What is the 2nd number in printer resolutions determined by?
the smallest increment that the drum can be turned
What does RET stand for?
Resolution Enhancement Technology
What does RET enable a printer to do?
Uses the printer’s RAM to print HQ jobs by smoothing out the jagged curves outlining characters using smaller dots
How many volts of negative charge does the primary corona wire or primary charge roller apply to the entire surface of the drum? What phase is this done during? (2)
~600 to ~1000 volts
The Charging phase
What does the Exposing phase do?
the laser creates a positive image on the surface of the drum (every part hit with the laser releases its negative charge)
[exposes it to light – the laser]
What happens during the Processing phase?
CPU processes the print request and sends the job to the print spooler (in PC memory) to queue up sequentially until Windows sends the job to the printer
What happens during the Developing phase?
The negative toner particles are attracted to the lesser negatively charged particles (negative toner -> positive drum particles) left by the laser to create a developed image
What hardware is used during the Transferring phase?
transfer corona/transfer roller
What happens during the Transferring phase?
To transfer the image from the drum onto the paper, the transfer corona/transfer roller gives the paper a positive charge to attract the negatively charged toner particles to rest on the paper
What are toner particles mostly made of?
Plastic (so the toner can be melted onto the paper)
What 2 rollers are used during the Fusing phase?
- a heated roller coated in nonstick material
- pressure roller
What happens during the Fusing phase?
2 rollers (1 heated non-stick, 1 pressure) melt the toner to the paper and a static charge eliminator removes the paper’s positive charge (that attracted the toner)
What’s a warning when using plastic media to print on?
The heated rollers can melt some types of plastic media and damage the printer and void the warranty (only use ones designed for laser printers)
(ones for inkjets don’t have to be heat resistant)
What component does the printer use during the Cleaning phase?
It scrapes the surface of the drum with a rubber cleaning blade
What happens to the residual toner removed during Cleaning?
it deposits the residual toner in a debris cavity or recycles it by returning it to the toner cartridge
After every page, the drum must be returned to a clean condition in what 2 ways?
- Physically
- Electrically
How is the printer cleaned electrically?
the erase lamp bombards the drum with light and the surface particles discharge into the grounded drum to leave a neutral-charged drum
