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At least not to my knowledge. I think there were some hefty downsides (prohibitive expensive?), probably no driver ICs existed, requiring a transistor based driver (too large and too expensive).
There were one or two LED watches using green LEDs - extremely rare and sought after, because they were expensive back then :)
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Yes, there were some green LED calculators. My first calculator was a Radio Shack 4 banger (Casio derivitive) and it came with green LEDs. It was a quality Casio calculator and used 2 AA batteries.
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I suppose that there were genuine green LED displays used in calculators, but most of the time the descriptions you refer to are given by ignorant people, or people who don't actually care that their description should be technically accurate..."LED means 'display' , right? and it's green-ish..."
On the same subject, how many time would you have seen plastic pouches and cases advertised as "leather"? It seems a lot of people don't know the meaning of the word...
Phew, it felt good to let that off my chest ;-)
Philippe
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I had one with a green LED. I think it was a bluish TI adding machine. I think I was two years old ('78/'79) when I was playing with it however.
Edited: 23 Feb 2010, 9:03 a.m.
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Hi Max!
I remember my dad bringing home a Sharp scientific calculator, the first one i'd seen (he had a 4-banger) - I was in primary school then. I was amazed that it had an exponent function. I always remember it having a green display and thought it was LED. Having searched the internet and from my memory, it was probably an EL-502 - which has a VFD display. So, I certainly can't recall any. I'll trust the great collectors on this forum on this topic - as if i'd doubt them in any case :-).
Bart
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There's an old thread: Green LED's?
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I doubt it. For many years green was the least-efficient of the LED colors. Even when blue was super expensive, it still gave more brightness for the amount of current than green did.
I had a calculator (Cannon, I think) with a truly green (not bluish-green) vacuum-fluorescent display in high school. The display was quite attractive, but the calculator finished off a pair of AA alkaline batteries in about three hours-- maybe less.
