Cree X Bright LEDS - Picture included

Long time lurker, first time poster.

Any thoughts on these?
I know different manufactures rate LEDs differently, but this could be very interesting......
Anyone have their hands on these?

<br>
<br>

"Prices start at $0.75 in 5k lots"

Group buy

www.optotech.com Welcome Floating Spots.

Ken

Those sound pretty sweet.

http://www.marktechopto.com/products/details.cfm?npd=55

Looking in their online catalog, I don't think I'm finding the new eXtra brights listed yet. I see plenty of Cotco "SiC" parts listed, but haven't found a white 5mm with 12,000mcd listed. These must be brand spanking new.

Could these be those mysterious new 12,000 mcd LEDs mentioned in a recent thread?

I had only half believed it.

Nope. They aren't.

I have received a sample of the LEDs and the white ones are definitely bluer than the current run Nacias, NSPW500BS series. For some odd reason, Nachia seemed to make their led "warmer" than my original lot of 5600mcd ones rec'd in 2001. But on a side note, the White CREEs to my eye, seem much brighter than the Nachia. I don't have yet a light meter, as the cost is prohibitive ($250+). Anyone know where I could get a light meter? I'm not looking for any fancy options like data logging as I am on a shoestring budget at the moment.

Question:

Looking at the data sheets, it would appear that the Cree LED in discussion has a 1/2 theta beam angle of 15 degrees. This would explain the higher mcd rating compared to the Nichia NSPW500 which has an angle of 20 degrees. This 10 degree overall difference in beam angle would explain a higher mcd rating even if the dies themselves put out equal lumens. Could this be the case? I also noticed that the LED's have a max If of 20 mA whereas Nichia is 30 mA and will put out more light than the specs show (based on 20 mA If)

Regarding e=mc2's comment on color, did you note the color rank on your latest batch of Nichia's? I think this could explain the disparity. Nichia even has a new 500BS with a dF color rank which they call "incandescent" and these really are warm to the point of being yellow white. They don't appear to be nearly as bright. I have forwarded some on to Craig but doubt he has evaluated them yet.

- Don

Originally posted by e=mc²:
I don't have yet a light meter, as the cost is prohibitive ($250+). Anyone know where I could get a light meter? I'm not looking for any fancy options like data logging as I am on a shoestring budget at the moment.

Click to expand...

<font size="2" face="Verdana, Arial">Here ya go! The Wavetek / Meterman LM631 is somewhat of a "deFacto standard" on CPF. This meter does EVERYTHING I need for $90 (w/S&H). Don't forget the "promotion code" for the free multimeter, it's really pretty decent.