Talk:Penning mixture

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Torr

Why is torr used in the sentence about plasma display pressure? "Several hundred torr" is both inaccurate and seemingly meaningless as the pressure of 1 atmosphere is 750 torr. Southsailor (talk) 04:21, 6 March 2015 (UTC)[reply]

   > Agreed.  While I don't know about the accuracy of "several hundred torr" relative to plasma display gas pressure, using torr is not a S.I. unit.  And since both of the references on the page are quite old, I would suggest new citations are in order.  If "several hundred torr" is still accurate for these displays, then perhaps using kPa would be a better choice.  To that end, 100 torr is approximately 13.3 kPa.  After 5 minutes of brief perusal of other Internet sources, I couldn't verify the accuracy of this pressure for plasma displays.  15:56, 10 December 2015 (UTC)  — Preceding unsigned comment added by Em3rald (talkcontribs)  

More efficient?

The article says it is more "efficient". Does that also mean it uses less energy per lumen, as well as having a lower striking voltage than a pure noble gas? --ChetvornoTALK 20:28, 15 April 2016 (UTC)[reply]

Yes and yes. A Penning mixture is one that exhibits the Penning effect.
In practice, the strike voltage is generally the more important than efficiency in lumens. Some lamps, and sodium is a good example, are all about efficiency (we tolerate the colour because they used to be the most efficient) but the efficiency here is all about sodium, not the gas fill. However their use of a Penning mixture (tiny bit of argon in neon) lowers the strike voltage by 5-10% and that's practically useful. For neon lamps though, no-one cares about efficiency. In some plasma displays 10-15 years ago (pre-LED) efficiency did become an issue and Penning mixtures were used specifically for that reason. In detectors (rather than lamps) it's about efficiency too, but that's a practical issue of sensitivity rather than lumens. Andy Dingley (talk) 22:22, 15 April 2016 (UTC)[reply]