Brand Newbie Q: Anyone have any opinions on LED mfrs...

Specifically, does anyone have any experience or opinion on the quality and
specification claims for the products manufactured by:

http://www.lc-led.com/

or

http://www.hebeiltd.com.cn/

They list very attractive specifications for incredible prices...almost sound too good to be true...

If not these, how about what manufacturers you believe to produce quality
and make reasonable specification claims.

Thanks...I'm trying to learn but what a confusing world of math, physics,
varying manufacturer specs...I think I'm holding my own in figuring it out...
after all I have a math and computer science background but man...it
can be confusing...

I find the luminous intensity and angle claims to be mildly useful for my
purposes...I am more interested in spectrum...but I want to compare
overall light output of LEDs with the same or very nearly the same
light spectrum output...does the following make sense:

I run a conversion
from mcd/deg of light dispersion to lumens and then use that number
for LEDs of only the same or VERY similar light wavelength curves (I
usually just use the peak wavelength--say Red 624 nm).

What do you guys think?

I typed my username in as a joke...can't believe someone hadn't sliced
off that piece of cheeeziness yet :wave:

Welcome!

What exactly are you wanting LEDs for? For the most part, I stick with Nichia CS LEDs, Peak Snow 29 LEDs, S/MJLEDs for 'white' LEDs and the LSDiodes.com THC3 100ma LEDs in blue and green. These are all known quality LEDs available reasonably cheap.

Well, I guess the simplest way to put it would be thus:

I want to create a very large array (or sets of arrays) of LEDs
to create the most ambient red light (615-640NM) as possible in a
somewhat small, confined space (all surfaces other than light
source to be mirrored or painted with high titanium white for
reflectivity). Point intensity is not so important...I want a lot of
light, not just intense points of it. I would like to stay under 35%
(under 30%--even better) of the energy requiremments of doing
this with more conventional means. I have a limited budget but
I don't mind invensting in quality upfront...I think the LED
technology/price point has arrived.

I need/want the most and best for MY money...I am just trying to
prototype a way of using light on a small, personal budget...This
could be a business for me if I can make the price point, quality,
etc of the finished product what I calculate...

Anywho, do any of the LED manufacturers you mention have
anything spectacular for red (615-640NM)...

I'll be looking but I don't want to
accidentally miss some gem...Hmmm, this gives me so many
ideas...LEDs may make me rich some day! :huh:

Nichia CS is generally considered the brightest 5mm LEDs, if I'm not mistaken... but with a slight blue tint towards the center of the beam. A CPFer sells them here: https://www.candlepowerforums.com/threads/100589

Just wanted to say Welcome to CPF Lumenary!

LSDiodes.com has the THC3s in red. If the blues and greens are any indication, they should be impressively bright but I can't run them at spec in any of my lights as I don't readily have a way of driving the 2.2-2.4V at 100ma.

But the greens and blues are VERY impressive for 5mm LEDs. Run on 2 alkaline cells (lower than suggest Vf) they are brighter than a Lux I cyan I have that runs direct drive at 3.6V. I literally couldn't beleive it.

Again, I have two of the THC3 reds (I killed one) but have never seen them perform their best but since you are doing a specific project, I assume you have the means to do the calculations to see how many LEDs and what resistors would be needed to make everything run in tip top shape.

Go over there and have a look at the specs.

Carrot: Wow! That is one bright LED!!! Unfortunately, the radiant
flux is very weak in the spectrum I require...I may have other uses
for it though...muha...muhaha...

CHC: Thanks for the warm welcome! I can almost feel the
candle power!

cratz2: Sweeet! That is one intense spec'd red LED. Unfortunately,
in the last day or two I've finally realized that I need to shift my spectral requirements a bit more red...maybe 639-665nm...the THC3 is just
outside...spec'd for 625nm peak and 630 typical...

Does anyone know what they mean by PEAK and TYPICAL in rating the
wavelength of the LEDs? Given the case of the red THC3 mentioned
above, does it mean that some lots of the LEDs have the highest level of radiant flux at 625nm but typical samples have peak radiant flux at
630nm--at slightly lower levels of radiant flux than when at 625, the
"peak?"

SunLED has LEDs rated for both 640nm and 660nm. They have agreed
to send me a small number of samples. Do any of you have experience
with or knowledge of SunLED prods?

I love this forum! Do guys know of any other good forums that also
include a quality discussion on LEDs???

Thanks so much!

What would I do without the internet and its community? I remember it
like it was yesterday...it was called the 80's...quality research and
collaboration took months or just didn't happen!