> I had a Brother Printer that was an LED printer about 10 years ago, it
worked
> great. I used it for years. It had a bar that went across the paper with 4
rows of
> LEDs. Very rugged machine, my guess it would expose UV film also. The LEDs
> looked red but I think they put out white light to fuse the toner to the
paper.
> Check around you may be able to find a used one to hack.
Surprisingly they still make those, they don't seem to be very common
though. They've been around for a while, I remember Brother & OkiData
models from over 20 years ago.
They work the same way as laser printers, except without the need to scan
the laser back & forth (so no moving parts). In theory that makes them more
reliable and faster, but they've always been a bit of an also-ran. I know
they'll do 1200 DPI, so the quality is ok. I don't know why they never
really took off, licencing issues maybe?
I've never bother to have a look at the innards of one. I assume the
technology is similar to the LED scanners you can get (Canon LIDE etc); LED
chips are pretty small so you can cram a few in there, but 1200 of them per
inch is rather impressive, especially across 8-11 inches or so. Staggered
maybe? Driving one of those would be an 'interesting' challenge, at 8"
that's 10,000 LEDs (triple for colour?)
There are also LCD printers, those just use a 'shutter' to control the
light. I haven't seen one of those for ages.
Tony