Mini-slide projector numeric display?

December 18, 2010 7:53 PM

What is this kind of numeric display called?

I saw a post somewhere that discussed a numeric display from the 50's-60's. As described, it had ten separate little lamps that, when lit, were like a little slide projector, illuminating a single digit.

I'd love to find this post, or more information. Maybe made in Russia?

posted by Marky to Technology (11 answers total)

Are you thinking of Nixie tubes?
posted by davey_darling at 7:54 PM on December 18, 2010

Nixie tubes.
posted by suedehead at 7:54 PM on December 18, 2010

Dammit, davey_darling!
posted by suedehead at 7:54 PM on December 18, 2010

Response by poster: Sorry, not Nixie tubes. This display was literally ten lamps shining through ten slides and ten lenses focused onto one screen, but about 2 inches high. It was used like a Nixie tube or LED display.
posted by Marky at 8:37 PM on December 18, 2010

Is it possibly a Light Pipe?
posted by lastchance at 9:01 PM on December 18, 2010

The generic term is "edge lit display". As in "edge lit holiday cards" or Scratchitti.
posted by anaelith at 9:05 PM on December 18, 2010

Best answer: I don't think it's what you're describing, but when I went to nuc. power prototype, we had two ancient counter/scalers for our GM detectors. One had nixie tubes for the display; the other was even older. It had several panels of nine indicator lights in a tic-tac-toe pattern. The lights had a template over them, so that when the light lit, it displayed a numeral. Each tic-tac-toe pattern had the numbers 1-9 in it and represented a digit of the answer. While the thing was counting, you'd see the lights blink on and off in sequence like a 50's computer of the future! It was awesome. I wish I still had that.

Maybe what you're describing is on this page, which is mostly about Nixie tubes, but scroll down to "The Shape of Clocks to Come" heading.
posted by ctmf at 11:02 PM on December 18, 2010 [1 favorite]

Best answer: Oh, yeah. That's got to be it. Try one-plane readout.
posted by ctmf at 11:08 PM on December 18, 2010 [1 favorite]

man, I don't even know what to google for the thing I remember, in case that was it.
posted by ctmf at 11:17 PM on December 18, 2010

Best answer: Nah, they're not the 'tic-tac-toe' type (we called them 'magic squares') displays and, although similar, they're not edge-lit or light pipes either - they're a true rear projection display just as Marky describes. In my old telco days we had a couple of event counters with them, and we just called them "RP counters" (where "RP" was short for "rear projection"). I'm pretty sure our counters were a locally-made thing, 'cos inside they were a mix of SE-50 (GEC/Marconi/BPO 4000-type) relays and earlier 2000-type (BPO) uniselectors. Likely the display units were from one of those manufacturers, though it's possible they came out of some military kit (many old-school exchange techs were ex-service pack-rats ;-)

There was another manufacturer-turned-generic term for them, and I'm wracking my brain to remember what it was, but I'm coming up with nothing at the moment.

(On preview: ctmf's got it, though they look positively modern compared to the ones we had! Pretty sure ours were made of Bakelite ;-)
posted by Pinback at 11:22 PM on December 18, 2010

Response by poster: ctmf's got it, with the web page I remembered! Thanks everyone!
posted by Marky at 9:35 AM on December 19, 2010