Re: [VAL] LED light fixtures?

[root <geraldj@xxxxxxxxxxx>]

LEDs are a moving target. The light output and efficiency numbers
increase with each new press release. The light spread increases slowly.
Getting a high intensity is easiest the more the light is focused from
the diode. And the designers have been superb at narrowly focused LED
optics.

Prices tend to be a bit high, but are coming down, partly from
competition.

I have a LED flashlight, I'm unable to tell the battery life, three
years so far on the first set of AA Alkalines (two cells) and I measure
the light output as being similar to the light output of my 3 D cell
flashlight that I've have since grade school. This has not been with
constant use, but with very intermittent use.

While a few months behind the news releases, Mouser Electronics
(http://www.mouser.com) has some LED replacements for automotive 12 volt
lamps in stock and at not quite the high prices of the most recently
announced products. Most of the LED replacements put the light out the
top of the lamp as most recent automotive applications are arranged that
way. Lamp sockets in my Caravel nearly all use the light out the side of
the lamp and since an incandescent filament radiates in all directions
it has equal output to that out the top. The incandescent lamp can get
efficiency from a reflector external to the lamp. The reflector is all
in the LED so we can't modify that light distribution so handily.

I see some LED replacements for lamps at Walmart in the automotive
corner. Red LEDs are more efficient and far better at color control than
an incandescent lamp behind a red lens for turn and tail signals. Many
centered stop lamps in recent cars and trucks use red LEDs and
noticeably get to full brilliance faster than the incandescent lamps in
the tail lights. At least its noticeable if you watch closely.

At the moment, area lighting from LEDs takes spreading many LEDs over
the area to be lit, they don't work well from a central fixture. Task
lighting though, can work well with LEDs providing the lamp holder can
be aimed at the task.

There is new news about LEDs for lighting in every issue of "electronic
products" magazine that I receive monthly. And sometimes news of a "new"
product that would have been news ten years ago, but a neophyte
publicity department didn't notice how far behind the product was.

Gerald J.