"Old Nick" wrote in message
...
Actually not quite. If you talk energy consumption then you are right.
But you can viciously overdrivve LEDs to get far more brightness out
of then than they normally can give.

see:
http://www.stockeryale.com/i/leds/lit/app001.htm

I know, I have used that principle to drive IR leds to illuminate a scenery
for the time of one frame of a video camera.

There is also argument that your eye and brain think that the led is
still alight and this can fool you into seeing a brighter LED. I would
reckon this would work best for LEDs being looked _at_, rather than
thiose used as a source of illumination.

Mmm.... I'd thought that the eye/brain combination would average it, but on
the other hand, the mind can do strange thinks. I'll might try it some day
by comparing two LEDs next to eachother, one continuously driven and the
other with a duty cycle.

Meindert