Convert Candelas per square inch to Foot-lamberts
Convert Candelas per square inch (cd/in²) to Foot-lamberts (fL) instantly and accurately.
Conversion Formula
fL = cd/in² × 452.3893421
About Candelas per square inch
The candela per square inch (cd/in²) equals 1/0.00064516 cd/m² ≈ 1 550 cd/m². Used in US LED and CRT datasheets when citing luminance of small emitter areas. A high-brightness packaged LED chip in a focussed-beam configuration can reach 1-20 cd/in². 1 cd/in² = 1/(0.0254²) cd/m².
About Foot-lamberts
The foot-lambert (fL) equals 1/(π×0.09290304) cd/m² ≈ 3.426 cd/m², the luminance of a perfect diffuse surface emitting 1 lumen per square foot. The SMPTE standard for cinema screen luminance is 14 fL (≈48 cd/m²); home projectors are rated 10-35 fL. Still standard in US cinema and theatre engineering. 1 fL = 1/(π×ft²) cd/m².
Quick Reference Table
| Candelas per square inch (cd/in²) | Foot-lamberts (fL) |
|---|---|
| 1 cd/in² | 452.389 fL |
| 2 cd/in² | 904.779 fL |
| 5 cd/in² | 2261.95 fL |
| 10 cd/in² | 4523.89 fL |
| 25 cd/in² | 11309.7 fL |
| 50 cd/in² | 22619.5 fL |
| 100 cd/in² | 45238.9 fL |