How to Convert Lux to Milliwatts
- 1). Divide the light's illuminance, measured in lux, by 683. With an illuminance, for instance, of 25,000 lux -- 25,000 / 683 = 36.6.
- 2). Look up the eye's sensitivity to the ray's wavelength from the first table in the first link in Resources. If, for instance, the light has a wavelength of 660-nm light, you'll see that the eye's relative sensitivity to it is 0.061.
- 3). Divide the answer to Step 1 by this sensitivity -- 36.6 / 0.061 = approximately 600 milliwatts of power.
