TABLE 1.

Summary of estimated sleep and associated light exposure.

Night	Lights off	Sleep onset	Sleep offset	Lights on	Sleep duration	Mid-sleep point
1	21:52	22:05	08:30	08:39	10:25	03:17
2	23:40	23:49	08:53	09:19	09:04	04:21
3	DL	00:45	09:01	DL	08:16	04:53
4	DL	00:47	08:28	DL	07:41	04:37
5	DL	01:14	09:14	DL	08:00	05:14
6	DL	02:12	09:53	DL	07:41	06:02
7	DL	02:43	06:10*	06:10$	03:27#	04:26
8	00:50	01:02	05:54*	06:01$	04:52	03:28
9	23:02	23:39	06:13*	06:23$	06:34	02:56

Lights off/on and sleep onset/offset times, nocturnal sleep duration and mid-sleep point (all derived from Kronowise ACM) each day of the study (expressed as hh:mm). DL is continuous dim light and, thus, lights off/on is not applicable during Stage 2. *Sleep offset was curtailed on those days. ^#Volunteer took a morning nap that day, thus the total sleep duration would be increased (Table showing only night sleep). ^$Indicates enforced lights on.