I have a panel with light indicators (LED) in RED,GREEN and YELLOW. Since the eye have different sensitivity to different colors, some colors must be brighter than others to be percepted as the same power (brightness).

LED's light emission are in mcd (milli candela). If, lets say RED is 1, in what ratio do I need to select GREEN and YELLOW so they are percepted as the same power (brightness) as the RED one?


1 Answer 1


The Candela is weighted by the luminosity function of the human eye, so in theory anyway you want them to be the same.

That's also why you don't see IR LEDs rated in mcd.


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