US Patent 11538641 Keyboard backlight module and applications thereof

A keyboard backlight module includes a light guide plate, a reflector, a light-emitting device and a first microstructure. The light guide plate has an output surface, a light guide pattern and a bottom surface disposed on an opposite side of the output surface. The light guide pattern is arranged on at least one of the bottom surface and the output surface. The reflector has a reflecting surface facing the bottom surface. The light-emitting device is disposed on one side of the light guide plate and configured to provide an incident light to the reflecting surface. The first microstructure is disposed on the reflecting surface, at least partially overlaps with the light guide pattern, and is configured to transform the incident light into a first reflected light.