On Oct 13, 2015, at 11:52 AM, tony duell <ard at
p850ug1.demon.co.uk> wrote:
The only other terminal I worked
with that could do that was a Tektronix storage scope terminal (4010
or 4014, IIRC). The Tek printer wasn't built-in, but it did take a
scan of the live screen, so that was similar. The paper was
silver-grey and I remember it coming out wet too. Everything else I
worked with was either thermal or dot-matrix impact, and could only
capture text as it arrived at the terminal, not a screen image.
The tektronix printer (or 'copier' as they called it) was photographic. The
paper was light-sensitive, and went past the screen of a 'flat' CRT (I think
it only had deflection plates for one axis, the 'deflection' in the other
direction coming from the paper movement). It really was an odd-looking
tube.
I've never seen that printer. But the tube you describe was common in the 1970s in
high end phototypesetting machines, such as the Autologic APS-5 and the Linotron 202. I
think the idea was to make high resolution CRT display feasible by having to worry only
about accuracy in one coordinate, not two. The film movement (actually paper, essentially
a roll of photo-print paper) would provide the other coordinate. Unlike the Tektronix
machine you describe, phototypesetter output was developed in essentially the same manner
as photographic print, with developer and fixer chemicals, in a machine that would take
the paper casette as input and produce the developed/fixed/dried roll of finished material
coming out the other end. The roll of paper would then be cut to separate the individual
columns and articles, and pasted onto cardboard page size boards to produce the finished
layout.
At some point, there were machines that could produce page-width paper, but those were
rather expensive and useful only once you got software to do the page layout on the
computer instead of manually in the composing room.
I believe that phototypesetting is obsolete now, though it hung on surprisingly long,
certainly into the 1990s -- because laser printout was high enough resolution to read, but
not good enough to use as the master for offset printing. I think phototypesetters were
good to 1000 dpi or thereabouts, unlike the 300-600 dpi of the first decade or so of laser
printers.
paul