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partial LED flux

Φv,LED,α ; ΦLED,α

luminous flux leaving the LED and propagating within a given cone angle, α, (centred from the LED's mechanical axis) that is determined by a circular aperture of 50 mm in diameter and the distance measured from the tip of the LED

Note 1 to entry: A detailed method of measurement is given in CIE 127 Measurement of LEDs.

Note 2 to entry: Partial LED flux is a quantity that applies to a single LED only and should not be confused with the term "partial luminous flux".

Note 3 to entry: The partial LED flux is expressed in lumen (lm).

Publication date: 2020-12
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