Re: Cateye Micro Halogen Headlights HL-500II vs. MC-200?

Bill Baka wrote:
SMS wrote:

Bill Baka wrote:

It wasn't made up. I am an electronics engineer by trade and the quantum physics are there for anyone to look up if they can understand them. The only heat loss is in the resistors used to limit the current to the LEDs so they don't get too much current and burn out.



In fact, managing the heat generated by the high power LEDs is very difficult, and Lumileds has whole papers dedicated to the subject.

"http://www.lumileds.com/pdfs/AB05.pdf";


The LEDs do get a little warm but not hot in the sense that anything is going to get hurt.
Bill

The figure used for incandescent efficiency is around 5%. That means 95% of the electrical energy becomes heat. LEDs of the kind used in bikes lights are less than 2x as efficient, so perhaps 10% -- 90% of electrical energy converted to heat. A 5W halogen will generate around 4.5W of heat, a 5W LED 4W, only slightly less -- there are electrical and optical losses which have nothing to do with quantum physics.
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