# What's the difference between lumen and mcd?

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• Anonymous

They explain a bit there : http://led.linear1.org/how-do-i-convert-between-ca...

And there :

"My old high school physics book has about a one page, really vague discussion of the candela and the lumen, and something called a solid angle, which is measured in steradians, and how a complete sphere is 4pi steradians, and a candela is the intensity of a source that gives off a lumen per steradian, that is, 4pi lumens. If you don't already know better, you can at least see the signs that something is missing in that brief description:

If the candela and lumen were really related only by a constant like 4pi, they'd just be different-sized units for measuring exactly the same thing. Why bother?

Using that formula blindly, you'd think a 2300 mcd LED gives off 29 lumens. That's about a thirtieth of the 60W light bulb, or in the same ballpark as my 2-1/2 watt bike headlight, out of less than a tenth of a watt of electricity. That would be an impressive LED, all right, but alas, those things that sound too good to be true.... "(1)

Here is a convertor : http://led.linear1.org/lumen.wiz

Another one : http://www.lpelectric.ro/en/support/lumeni_en.html

• Anonymous
4 years ago

Lumens To Mcd

• 5 years ago