Or General Radio - they used edge-lit displays in some
test equipment.
NLS and General Radio are the ones that spring to mind, but there were
some military units that could have been HP. AN/TSM-16 maybe.
HP had 1-of-10 'thermometer-style' displays in
the 50s and early-60s but
started switching to NIXIEs quite early (1959 or earlier).
I think they bought that technology? I can not remember who now - I
almost want to say from Beckman.
--
Will