designer's own words:Bed lights create a comfortable and cozy environment that helps people to fall asleep with ease. However, once people are asleep, they do not recognize that the light is on so the product becomes neglected, causing unnecessary energy to be used. If the lighting time can be controlled, this unnecessary waste can be reduced. Users can set the time to their preference, and once they fall asleep, the light changes from a full moon shape to a half moon, a crescent moon then automatically turns off, just like a total lunar eclipse. The product is an eco-design concept that lets users set the energy usage level on their own and practice saving energy.