This calculator allows calculation of luminous flux (lm) from luminous intensity (cd) and conical apex angle (°).
LEDs are often described as having some luminous intensity and a viewing angle. This calculator will give the total luminous flux.
The calculator assumes uniform flux distribution though the apex angle, but in reality flux will vary. Using a lower 'average' luminous intensity is one method of adjusting for non-uniform distribution.
If power is provided, it also calculates luminous efficiency.
If radius is given, it also calculates luminous flux.
The results can serve as a saneness test on published product claims.
The calculator does not do a lot of error checking, if you enter nonsense, it will probably produce nonsense.
© Copyright: Owen Duffy 1995, 2019. All rights reserved. Disclaimer.