B Does Combined Luminosity of LEDs Add Up?

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The combined luminosity of a green and red LED, each with a luminosity of 2 W, is generally considered to be 4 W when measured together. However, the actual output can vary based on the angle of emission, as the LEDs are not isotropic emitters. This means that if the LEDs are not aligned properly, the effective power received from each may differ. Therefore, while the theoretical total is 4 W, practical conditions can affect the perceived luminosity. Proper alignment and orientation are crucial for achieving the expected combined luminosity.
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Say you had a green and red LED, both with a luminosity of 2 W would the combined luminosity be 4 W or still 2 W?
Say you had a green and red LED, both with a luminosity of 2 W would the combined luminosity be 4 W or still 2 W?
 
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Euan12345 said:
Summary:: Say you had a green and red LED, both with a luminosity of 2 W would the combined luminosity be 4 W or still 2 W?

Say you had a green and red LED, both with a luminosity of 2 W would the combined luminosity be 4 W or still 2 W?

On the face of it, I would say 'yes', since luminosity is a measure of total output power. However, your sources aren't isotropic emitters: the radiance of these sources strongly depend on the angle with respect to each emitter's surface normal.

What that means is that if the sources are not facing the same direction, the received power from each source is likely different.
 
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