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Very early LCD displays

I picked up some these curiosities in a car boot sale, no known history. Anyone have any info , particularly date.

They are made of 2 sandwiched very thick 1/8 inch glass slabs with obvious epoxied over liquid filler-holes, otherwise size etc is much the same as modern, standard sloping 7 segment displays, conductive lands and traces etc. These ones 3 1/2 digit and annunciators for DVM. No built in polarizers. The segments go cloudy white on 40 to 60V ac drive, the same between added polarizers. Wrapped in tissue paper, then expanded polystyrene and original cardboard wrapping , new unused, made by Hamlin Inc, type number 3601-0

Reply to
N_Cook
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I have seen early LCDs that behaved just like that. The "cloudy white" you describe is how the display is used in practice; there would be some sort of edge light to enhance the effect, but the display sort of stuck out the top of the box (in this case it was a calculator) and you could see right through it. As I recall, it also was very slow (by today's standards) in switching between "on" and "off".

Isaac

Reply to
isw

obvious

polystyrene

There were, with them, what I thought were more recent so left unlooked-at , wrapped watch displays. But some dates in there for the 3302 type , were

1973 and 1974. I cannot get any sign of life on any of them, up to 60 volts ac. No staining in the tissue paper of leaked liquid, surely not 100 volts or so? Distinctive gold evaporation semi-transparent coating on one side of them and similar obvious stopped filler/vent holes. Must be contemporaneous as both 3601 and 3302 along with 8 digit 3501 and clock display type 3401 shown on the packaging.
Reply to
N_Cook

The first pic shows the effect of 60V ac on one segment relative to back-plane, and a piece of matt black behind one part of the "1"

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watch display, gold coating obscuring scanner view, both sides
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packaging
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-- Diverse Devices, Southampton, England electronic hints and repair briefs , schematics/manuals list on

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Reply to
N_Cook

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