🚀 go-pugleaf

In article <862@ritcv.UUCP> cep4478@ritcv.UUCP (Christopher E. Piggott) writes:
>I have several, but have no idea where they came from.  (They look more
>purplish than blue to me, as if they were red L.E.D.'s with blue paint
>mixed into the glass.  I have technical reasons to suspect this, also: they
>are not as grossly enefficient as blue L.E.D.'s should theoretically be).

	I'm not sure (therefore I know I shouldn't post this...), but I
doubt that your blue LED's could possibly be red LED's with a blue filter.
This seems impossible since LED's (which, with red are GaAs? gallium
arsenide) are second cousin's to semiconductor lasers, and are very
monochromatic. Just try to view a red LED through a green or blue interference
filter -- you'll see nothing. Therefore output in the blue region is nil
as well.
	In any case, I also believe that blue LED's are fabricated from
silicon nitride. BTW, why should a blue LED necessarily grossly
inefficient ? I do believe that blue LED's made from silicon nitride are,
but why must a blue LED (regardless of implementation) be inefficient.
	As far as why your blue LED appears purplish. It probably is
psychophysical/physiological, rather than any red output. Just as the
extreme shortwavelength end of the rainbow appears violet/purple, the
blue LED probably is emitting light at, say 430nm. Your red cones in the
retina actually have significant sensitivity in the deep blue region --
more so than your green cones. Thus deep blue appears purplish or
actually bluish/red, an anomolous sensation.