Figure 1.

Light profiles, in photopic illuminance (solid gray, left ordinate scale) and in circadian stimulus (solid black, right ordinate scale) units [37], for two women working in daylighted offices in Troy, NY, USA. Measurements were made continuously starting at 15:00 on 1 December 2005 until 14:30 on 2 December 2005. Also shown are vertical photopic illuminances (dashed black, left ordinate scale) expected from outdoor exposure to a partly cloudy sky at the same location on the same date in open country for a 45° azimuth angle from the sun [26].