Cree XR-E LEDs
So I received a little package today.
Cree XR-E LEDs and Ledil lenses
Three Cree XR-E LEDs (P3 bin) and three Ledil 4 degree lenses.
You know what that means! More bike lights!
The XR-E's are pretty scary. One running at 700mA is enough to comfortably light my bedroom. They're impossible to look at.
Cree XR-E LED
I took the opportunity to compare the three major LEDs that I have handy: a 3W Luxeon with Fraen narrow lens, a Cree 7090 with 6 degree Polymer Optics lens, and a new Cree XR-E (unlensed).
I ran the three off the same 700mA supply that I used for my MTB lights. I bounced the light off my ceiling to get a better idea of the total light output, because they all have different lenses. I haven't compensated for the forward voltage drop; they're all running at 700mA. Finally, the shots are all taken at 1/50th of a second through a Canon 50mm F1.4 lens.
Splash test 1: 3W Luxeon at 700mA (2.45W)
Splash test 2: Cree XLamp at 700mA (3.15W)
Splash test 3: Cree XR-E (P3) at 700mA
Re: heat sink ?
Nope; take a look at the datasheet for the lens if you're not sure. You get the lens, and it has a sticky pad on the back. That's it. You have to supply your own heatsink.
Keep in mind that you don't need a whole lot of heatsinking. The lights of built with these (which I'll be writing up soon, honest!) just have a small aluminium bracket and they don't even get warm. Some people are taking it way too far with their copper-inlaid heatsinks and ducted air :-)
Cree XR-Es work well
Hi Ian,
I've also been building LED bicycle lights. I just upgraded my single Luxeon III to a Cree XR-E with Fraen FC optics. The difference is impressive, as shown by the beam shots. A triple XR-E light will be brighter than a 20W halogen. I did this test on the weekend and the results are
http://www.ghostgum.com.au/misc/BikeLight.htm
Note that some of the info I wrote in a previous comment on your blog is no longer current.
http://www.mouldy.org/projects/Ultimate-Luxeon-K2-bike-lights
The data sheet for the XR-E has changed. 1A drive current is now Ok, but with reduced efficiency. The beam width is 90 deg not 75 deg, so the older 7090 optics should be Ok.
Source for Cree XR-Es and Optics?
Can I ask what your source for the XR-Es and Ledil optics is? Thanks!
heat sink ?
Hi
Thanks for your article on this.
Do these Ledil lenses come with a fitting heat sink ? On cutters.com.au
I find the following information
"Integrated holder. Fastening to heat sink with a PU foam adhesive tape of automotive grade" but I'm not sure whether a heat sink and the PU adhesive
tape are included ...
Thanks