Orange Gas Plasma displays

[Chuck(G)]

Perhaps my memory is playing tricks, but I thought I once saw ones described which could produce different colours at different AC frequencies. Have you heard of that?

Yes, but the color doesn't change much--maybe green to blue-green. The other issue is that each phosphor has its own peak emission spectrum; varying the frequency significantly dims the color. So it's not terribly useful in that respect.

At one time Planar was working on a full-color display, but I don't think it ever got anywhere. Right now, they're trying to fend off OLED as competition.

Here's a little paper that talks about the technology.

At one time (1960s), EL was a very hot area, predicting things like walls of rooms providing illumination, wearable lighting (EL can be made to be flexible) and all manner of things. Sadly, it never got very far.

Right now, the most promising application appears to be outdoor advertising displays:

 

[Neosodium]

The Panasonic Portable (luggable) JB-3300 also has an orange gas plasma display. http://www.eolith.co.uk/Panasonic/JB-3300.html

Ericsson Portable PC 8400-005 is very similar and looks to have used the same panasonic PDP display as the other contemporary machines.