On Sun, 21 Oct 2007 13:14:04 +0100, Mike Williams
wrote:

Wasn't it who wrote:
Thus spake Les Hemmings ) unto the assembled
multitudes:

The new LED cats eyes on the M20 leave trails like tracer shells in my
mirrors at night. And if i move my eyes i can see the flicker too...

Coo, is that what they are? How are they powered - is it just by the light
of oncoming vehicles? There are some similar such items on the eastbound
A27 for a stretch after you exit the Southwick tunnel.

http://www.aixtron.com/press/0211e.htm

"Power is generated via solar cells and a storage battery."

But if that's the case, it's odd that they flicker.
Not really.
The most efficient way to drive LED's, is with a PWM drive. This is
what is done with all the LED car light, and given the 'storage
battery' voltage won't match the requirements of the LED's, this is
the way the cat's eyes wll be done.

Best Wishes