Marshall Brain's Blog

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The idea is so simple once you see it that your why-didn't-I-think-of-that circuit nearly shorts out from the overload:

Terrorist-Proof Lighting Illuminates Without Power

From the article:

AEP has developed a bomb-proof bulb that glows in the dark, literally, when the power has been turned off (even if the bulb breaks)... The bulbs combine a newly patented proprietary scotopic phosphor blend with a non-radioactive after-glow phosphor blend that provides illumination, helping the human eye adapt more quickly to sudden low-light conditions in an emergency power outage.

The gist of the idea is, "Let's paint bulbs with glow-in-the-dark paint so that they glow after you turn them off." What could be simpler than that? In this case, it would appear that they are mixing the glow-phosphor into the light-phosphor that is already present inside the fluorescent tube -- a nuance that is even more brilliant. It's not the sort of bulb you would want in a bedroom probably, but in any sort of office or industrial environment it would be perfect.