The Facebook CEO, Mark Zuckerberg 34, took to Instagram to inform followers of his latest invention and the reasoning behind it.
The ‘sleep box’ emits a very faint light between 6 am and 7 am, when their daughters Max and August usually wake up.
The box doesn’t show the time as that would cause stress for his wife Dr Priscilla Chan, 33, and disrupt her sleep, the billionaire tech entrepreneur said in an Instagram post.
He explained: ‘Since it doesn’t show the time, if she wakes up in the middle of the night, she knows to just go back to sleep without having to worry about what time it is.
‘So far this has worked better than I expected and she can now sleep through the night.’ He said.
The post garnered a number of comments online. Former Facebook manager and angel investor Dave Morin called the device, ‘Genius.’