This calculator is useful for calculating the luminous flux for LEDS where the angle is known.
1 candela of luminous intensity equals 1 lumen of luminous flux per steradian of solid angle, where a steradian respresents a cone whose surface area at the end equals the length of the cone squared.
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where:
- Φv is the luminous flux, in measured in Lumens (lm),
- Iv is the luminous intensity, measured in Candela (cd), and
- Ω is the solid angle of the beam is measured in Steradian (sr).
Conversion from beam angle to solid angle (sterians) is done with this formula:
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where:
- θ is the the beam angle measured in degrees.
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Enter any two known values and press "Calculate" to solve for the other.