We have a similar thing but it is slightly different in the sense that it aims to simulate a natural sunrise.

Essentially half an hour before you set your alarm it will start to gradually get brighter and brighter. This is meant to be a more natural way of waking up as opposed to a harsh alarm sound.

Two main brands are Lumie and Philipps, perhaps these haven't caught on so much in the US but in UK where sunlight is rare they are really good!