Convert Microlumens to Watts (at 555 nm)
Convert Microlumens (µlm) to Watts (at 555 nm) (W₅₅₅) instantly and accurately.
Conversion Formula
W₅₅₅ = µlm × 1.464128843e-9
About Microlumens
The microlumen (µlm) equals 10⁻⁶ lm. LED indicators in deep-sleep power-save mode, fiber-optic signal pilots, and OLED display pixels at minimum brightness fall into this range. Equivalent to a 555 nm source radiating approximately 1.46 nW of radiant power. A night-vision display backlight operates at 1-100 µlm. 1 µlm = 10⁻⁶ lm.
About Watts (at 555 nm)
The watt at 555 nm equals 683 lm exactly, by the 2019 SI definition fixing the luminous efficacy constant K_cd = 683 lm/W at 540 THz (≈ 555 nm, the peak of the photopic eye-sensitivity curve V(λ)). Used in LED optical design and photonics research to convert between radiometric power and photometric flux at peak eye sensitivity. 1 W₅₅₅ = 683 lm.
Quick Reference Table
| Microlumens (µlm) | Watts (at 555 nm) (W₅₅₅) |
|---|---|
| 1 µlm | 1.464 × 10-9 W₅₅₅ |
| 2 µlm | 2.928 × 10-9 W₅₅₅ |
| 5 µlm | 7.321 × 10-9 W₅₅₅ |
| 10 µlm | 1.464 × 10-8 W₅₅₅ |
| 25 µlm | 3.66 × 10-8 W₅₅₅ |
| 50 µlm | 7.321 × 10-8 W₅₅₅ |
| 100 µlm | 1.464 × 10-7 W₅₅₅ |