Figure 2
From: Optimized office lighting advances melatonin phase and peripheral heat loss prior bedtime
Individual light exposure (Ev) from wearable light sensor devices across the entire waking period. Time course of averaged individual illuminance (Ev) from wearable light sensors recorded across the entire waking period, averaged across 5 days (mean values ± SEM; Test room = red lines and circles, n = 30; Reference room = blue lines and triangles, n = 33). The x-axis at the bottom shows elapsed time since habitual midsleep (h), and the upper x-axis depicts corresponding clock times. The horizontal arrows show the time in the offices (light grey arrow) and the lunch break (spent outside the office; dotted grey arrow).
