Point Source Irradiance calculator
Solid angle and irradiance on a detector from an isotropic point source.
Category: Radiometry
Formula: E = P/(4πd²) · Ω = 2π(1 − d/√(d² + A/π)) ≈ A/d² · Pdet = P·Ω/(4π)
Inputs
| Input | Parameter | Unit | Default |
|---|---|---|---|
| Source power | P | W | 1 |
| Distance | d | m | 1 |
| Det. area | A | mm² | 10 |
Result with the default inputs
- Irradiance: 0.0796 W/m²
- Solid angle: 1.0000e-5 sr
- Power on det: 7.9577e-7 W
Open it with your own values: put each input in the address as a parameter, for example /calculators/point-source-irradiance?P=1. A unit other than the listed one goes in <parameter>_unit.
Read more: Wikipedia: Inverse-square law