Printers: Basic Questions

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Printers Basic Questions

• price - and running costs?
• compatible with your computer?
• colour or black and white?
• speed of printing?
• what resolution?
• amount of paper the tray can handle?
• will it take the paper sizes you want to use?
• do you need to print envelopes?

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Dot Matrix Printer

• price the least expensive printers.
• basic idea a print head with small blunt pins
  hits an inked ribbon like a typewriter except
  that the same pins produce all char-acters. The
  precise configuration of pins changes - to allow
  different characters to be represented -
  according to the instructions sent by the
  computer.
• speed in the range 1 to 18 pages a minute

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Dot Matrix Printer - 2

• resolution poor for 9 pin fair for 24 pin.
• noise level high
• ink on the ribbon - replace it when dry
• paper single sheet or continuous fanfold
• SUMMARY - old, but worth considering if price is
  more important than output quality or quietness.
  Ideal for multicopy forms - the impact is needed
  to print through carbons.

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Ink Jets

• price cheap to middle range
• basic idea a print head sprays ink through small
  holes onto the page
• speed in the range of half to four pages per
  minute
• resolution 180 to 720 dots per inch
• noise level low

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More on Ink Jets

• ink in cartridges - replace when empty
• paper single sheet. Most ink jets will take
  envelopes, labels and transparencies.
• SUMMARY widely used, offering high quality
  output relatively cheaply. Colour ink jets are
  especially popular, being much less expensive
  than laser printers but still giving good results.

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Laser Printers

• price middle to top of the range
• basic idea in essence a copier. Instead of
  dealing with characters it simply produces a high
  quality photocopy.
• speed between 4 and 30 pages per minute
• resolution 300 to 1200 dots per inch
• noise level low

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More on Laser Printers

• ink a fine powdered ink, toner, is stored in a
  cartridge. Replace when empty.
• paper single sheets up to A4 and higher,
  envelopes, labels and transparencies (the last
  must be for laser or photocopier use)
• colour output from colour laser is dearer than
  that from colour inkjet, but better.

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Still More on Laser Printers

• multifunction some laser printers do other jobs
  - faxing, scanning and photocopying
• memory because of the way they work - storing
  pages before printing - lasers have at least 1 MB
  of memory, often a lot more. For high resolution
  (600 dpi) and/or complex graphics and/or A3
  output, a lot of memory is needed.

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Finally on Laser Printers

• Laser output requires a printer language,
  software to tell the printer how to print. There
  are two types of printer language
• PCL Printer Control Language. PCL lasers are
  fine for routine office work cheaper but with
  less graphic capability than ...
• Postscript lasers, able to print complex
  graphics, fonts and colours. Very popular in
  graphic design environments.

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For a readable account of laser printers,
try this web pagehttp//www.dungeon.com/poota
/lpbook/01-chp1.html

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Other Types of Printer

• Solid Ink high quality but relatively cheap
  colour images on paper or transparency
• Thermal-Wax sharp, rich images that dont smear
• Dye Sublimation also known as thermal dye
  transfer printers very expensive but producing
  images that look like colour photographs.

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Fonts

• Character sets of a given design and size. The
  font used here is Times New Roman ..
• .. this is Arial
• Most printers come with built in, resident, fonts
  (you can add to them). Resident fonts print
  faster than those on your computer.
• There are two basic kinds of font TrueType and
  Bitmapped

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Buffers and Spoolers

• Computers send data much faster than print-ers
  print it. To avoid the computer waiting, data is
  dumped into an intermediate store for release to
  the printer at a manageable speed. This frees up
  the processor for other tasks.
• These intermediate stores take two forms
  buffers and spoolers

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Buffers Spoolers - 2

• A buffer is a section of printer memory that
  receives the computers output. When the buffer
  is full, the computer must wait before sending
  any more..
• A spooler is a program that stores informat-ion
  ready for printing on the computer. Far bigger
  documents can be stored on spoolers than on
  printer buffers. Windows comes with a built-in
  print spooler.