How bright are we talking here
this post was submitted on 11 Sep 2025
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Good question and I'd like to know. From the linked paper in the linked article,
(445 nm; 1.25 W/cm2)
Sunlight is 1000W/m2, which I believe to be the sum of all wavelengths. 1m2 is 10,000cm2, so their light would have a total energy of 12,500W/m2 if I did my metric right. I've wandered into a field I don't have all the info were.
rerouting
Let me try running around in Watts. I picked out a royal blue, 450-465nm Cree XE-G LED from LEDSupply. At max 3,000mA, forward voltage is 3.7v. That's 11.1W of energy consumed. I'm not sure how to find an exact efficiency ratio, but Wikipedia puts it around 30% light, 70% heat in the page on "thermal management of high power LEDs). For reference, incandescent is about 10/90%. From there, I'll round down for optics and call it 3w total light. That gives you the light output density for 2.4cm2, or an 18mm circle, or like a 3/4" circle, or a little less than a US penny. All with a fist-sized heatsink and a fan. Per LED.
I think.
About 1.25 W/cm2
Welp I guess it's time for me to get some blue torches.