. Author manuscript; available in PMC: 2012 Jul 1.

Published in final edited form as: Cancer Epidemiol Biomarkers Prev. 2011 Jul;20(7):1341–1349. doi: 10.1158/1055-9965.EPI-11-0204

Table 1.

Estimated corneal illuminance provided by the Lighting Research Center, Rensselaer Polytechnic Institute (Troy, NY).

Assumed application	Estimated corneal illuminance
H…Halogen Lamp residence	20 lux
F…Fluorescent Lamp office	100 lux
I…Incandescent light residence	20 lux
O…Other Artificial Light Source^*	10 lux
N…Natural Light (Indoors)	200 lux
S…Sunlight, Natural Light (Outdoors)	2000 lux
D…Darkness, suburban night sky	0.2 lux

Mostly low light levels like TV in otherwise dark room, or candle light, or PC (information from diaries)