Tuesday, June 26, 2007

LED bulbs brightness

We all kind of know by now that LED bulbs last long. In fact that is the one thing manufacturers try to keep to. At the expense of other things like brightness. (And still some bulbs don't last.)

So here we go, I investigate this further.
All LEDs are very sensitive to even minor fluctuations in current.
My thinking is that because bulbs are built from many such LED units (with ever so slightly different qualities) they have to be under-driven to keep them last long. And that what most responsible manufacturers do. Problem is, this will affect brightness.

Lifetime is straightforward - you see when your LED dies. Brightness is a little murkier subject. There is candela, lumen etc. Luminous intensity itself is measured in various circles with various depth. Also LEDs are narrow beam "bare lights", so to compare them to compact fluorescent bulbs or to the now trendy long life light bulbs (incandescents) that are housed in a luminaire (or armature) doesn't compare apples with apples.

But let's check out others opinions.

cons (mostly)

Otherpower had a different position. But they recently reviewed it and them seem to be saying that on the whole they are not as bright as claimed.

Not surprisingly, Don Klipstein , the undisputed LED guru seems to be saying the same as he has been doing for some time now. He even calls screw in and other LED bulbs for incandescent replacement a "hype" for the most part.

Rob 'Linear' Arnold has a very thoughtful points about a catch 22 for household LED bulbs in the US: Underwriter laboratories (UL) doesn't see the need to list them, and surveyors doesn't see the need to approve them with UL listing. So there you go.

Pat Mullins is not convinced about the proper heat sinking of screw-in LED replacement bulbs. I tend to share hat opinion, I and haven't change it.


Pual Matthews has a good point on the single color department. This he says in favor of LED "bulbs" since LEDs don't need filtering to create colors. And filters take a lot from brightness. Point taken.


I still think secondary heat sinks (not just the aluminum plate in the junction) is needed for good brightness performance. And since the best of those is still for external flood light, I am going to assume that the rest is very promising, but in development for now.


My LED shop opens on fun-LED Side!

Go check it out. Leddies LED light shop opens on fun-LED Side.
And there it steadily grows.

I chose Amazon to build it with (aStore) because it gives me good control over product selection. They have competitive pricing and they pull unreliable brands.

Didn't stuff my store just with anything. Built my own Categories / subcategories sturcture.

LED bulbs update is coming

But this blog also has the purposes of parking information while rearranging fun-led-light my LED light guide. And have I been busy!

What keeps me very busy in my spare time is the full update of the site with style sheets (CSS.) I find it a pain in the neck that old tables constructed without styles are poorly handled by sheets when it comes to consistency. In particular, IExplorer seems to have it's own mind how to read the styling.

But enough of that.

Meanwhile, I am also slowly updating my info on LED light bulbs. Why you ask? It's because the information I am getting doesn't seem consistent and sometimes outright misleading. Forecasting the future is one thing. But it is badly needed to sort out stuff all the same.