bof wrote:
In message , Dave
writes
Cynic wrote:

LEDs are inherently more directional than other forms of lighting.
That is in fact a good thing, because any light that is illuminating
areas you don't *need* to be illuminated is wasted energy. Coverage
angles are increased either by mounting several LEDs at different
angles, or with suitable optics (usually diffuser/lens combination,
which increases the price).

As far as car running lights go, they are rubbish. Look at the angle
of view they disapear at on a Mercedes. It is very narrow.

At night I find the on/off flickering of LED brake lights particularly
annoying, why not have interleaved arrays of LEDs that turn on at
different times to give the effect of a constant light?

Why not just make them flash about 100 times faster, i.e. about 100kHz
rather than about 1kHz or thereabouts that a lot of them currently do?

It really is not hard to make LEDs flash on and off. Tens or hundreds
of MHz is easy and routine. So 100kHz should not be a problem at all.

No, I suspect the flash rate is *kept* down to MAKE the flash just
noticeable, to make the car look "flash" by standing out conspicuously
from those cheaper cars with mere incandescent brake lights that do NOT
flash. It's for posing.

Regarding the other poster not being about to see the flashing: I've had
a technique for detecting very rapidly-flashing lights since I was about
10 and starting in electronics with 555 timers making bulbs and LEDs
flash at varying rates. You kind of "flick" your eyeball as quick as you
can between looking up, above the flashing light, and then down, looking
below it. What you see is a broken (dashed, or dotted) trace that gets
left on the retina, which persistence of vision allows you to see, and
analyse. So you not only get to estimate the RATE (Hz) of flashing, but
also, the mark-space ratio, or duty cycle.