Scor­pio News


October–December 1988 – Volume 2. Issue 4.

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The Laser printer works in exactly the same way, except there is no paper original as with the photocopier. It stores the image to be printed in a large area of memory of its own, and when the image is complete, it starts to print. Again the self same properties of the Laser, which make it so attractive in the optical disk come into play, namely, the ability to focus the light to a very fine spot and to switch it on and off very fast. The laser scans the drum using a swinging or rotating mirror and switches on for white dots and off for black, this way it draws lines of dots on the drum – the self same dots which went to make up the image in the computer memory. The rest of the story is the same as the photocopier.

We established that there were some 8 million dots on an A4 page scanned at 300 dpi, and that’s a lot of dots. These dot patterns have to be transferred from the computer memory to the printer memory, and if left to the traditional methods of connecting printers to computers, would take until the middle of next week ! Some imaging systems do just this on grounds of cost, as the electronics to do it are all present inside the printer, it’s just that they weren’t designed to transfer huge lumps of graphics, and as a result, are very slow. Better systems replace the data transfer system with one of their own. This is usually built into the computer which takes the existing image in the computer memory and dumps it, very fast, straight at the Laser in the printer, by-passing the printer memory and most of the intervening printer electronics. More costly, but a lot faster.

That just about wraps up the technical side of it. I hope I’ve explained the workings adequately. But before going on to my pets hates and prejudices regarding the software used to drive it all, just a few words about what else can be done with the hardware.

Other uses.

Most of the kit shares a lot in common with ‘Desk-Top Publishing’. In fact, the Imaging System in it’s idle moments becomes a very effective DTP (another acronym: Desk-Top Publisher/​Publishing). Not that I would suggest for a moment that the optical disks be used for storing the DTP output, that would waste space and anyway, DTP output is best directed at the computers’ hard disk – but it works very well indeed.

Another area is FAX, a means of communication which has been in the doldrums for the last 20 years. Now as Japan Inc. has found itself running out of sales for its photocopiers, they’ve bent the technology to FAX and with typical Japanese sales technique have brought the market into the 1980’s. It’s now ‘the done thing’ to have FAX in the office. The Imaging System only requires the inclusion of a suitable FAX modem (yet another acronym: modem – MOdulator/​DEModulator – a device for sending digital data over the phone line), and a piece of communications software, and the Imaging System is a FAX machine in its own right. Not only can

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