🚀 go-pugleaf

IL wrote in message ...
>Can you enlighten me?
>I am doing a project and need to find out about the different technologies
>used for Photocopying and Scanning.

All toner based printers and copiers get toner onto the paper using a
photostatic drum or belt. Laser printers/copiers charge the drum using a
scanning laser modulated by electronic means.  LED printers charge the drum
using an array of Light Emitting Diodes.  Conventional photocopiers charge
the drum using a direct reflection from the copy source which is illuminated
by a single white light.

> I would like to distinguish between
>colour and b/w processes. I am particularly interested in the different
>light sources. For example, do laser copiers use laser light? Do colour
>copiers use white light or do they use some combination of coloured lights?
>Any information would be much appreciated.

I am not real familiar with colour copiers so I'll talk about scanners.  B/W
only scanners commonly use a green light to illuminate the source which
reflects onto an array of photo detector thingys(reaching the limit of my
knowledge :) ).  Colour scanners mostly use a single white light although
typically older and more expensive scanners use RGB tubes and detect each
primary colour separately.

Some Examples:

1. HP Scanjet 5100C - Single white tube - full colour
2. Mustek B/W Handscanner - single green tube - 256 grey scales
3. Epson GT9500 - RGB 3 tubes - full colour (I want one!)

theGoob
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The above advice may contain factual errors notwithstanding due care.
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