I wear my "old" Vivoactive HR day and night. This model measures the heart rate during sleep time every few minutes. Most of the time the optical heart rate sensor is dark and not disturbing. I do not know when and why, but sometimes in the night the green light of the sensor flashes up and gets very bright. If not in a deep sleep phase and the watch is next to my eyes, I wake up from that bright light.
As far as I know, the new Vivoactive 3 has an improved sensor that measures the heart rate more often (every second?). Does this mean that the light of the sensor keeps switched on the whole night? Has anyone made an annoying experience with the Vivoactive 3 light of heart rate sensor during sleep time?
