From: John De Armond
Subject: Re: want LED tail lamps to replace bulbs
Date: Fri, 15 Oct 1999 00:15:03 EDT
Newsgroups: rec.outdoors.rv-travel

Tom Fisher wrote:
> 
> Is anyone using the white LED's for interior lighting?
> It seems like they would be much more efficient than
> incandescent and/or flourescent.

I use triphosphor white neon tubing for lighting.  And when you note
my .sig, you'll understand why :-)  Actually I'd expect that modern
neon using the triphosphor (offshoot from developments in the
projection TV industry) white tubing and solid state transformers
would be at least as efficient as white LEDs.  White LEDs also use a
phosphor to get the white light so the same stimulated emission
mechanism with its attendant inefficiency is at work.

For example, I can drive 12 feet of 15 mm dia white tubing from a
solid state transformer about the size of a small pager that draws
but 800 ma.  That's 9.6 watts.  A wide range of "white" colors are
available, from bluish daylight to the reddish 2800 deg kelvin
"incandescent" color that is designed to make light resembling that
from tungsten lamps.  The surface brightness of a 15 mm tube is
about half that of a normal fluorescent light so the lighting is
very soft and lacks harshness, even when reading glossy magazines. 
An additional advantage is that when the tube is properly made and
protected from breakage, it will last essentially forever.  Then
there's the fact that neon can be bent to fit around almost any
shape.  The only disadvantage is initial cost - we neon guys like to
get paid so we can keep buying these motorhomes :-)  Figure $6 per
installed foot plus about $30 per solid state transformer.

John