US Patent 12087522 Backlight module and keyboard thereof

A backlight module is applied to providing light to a plurality of keyswitches of a keyboard. Each keyswitch has a keycap and an elastic member abutting against the keycap. The backlight module includes a membrane circuit board and a light guide plate. The membrane circuit board has a light emitting diode corresponding to the keyswitch. The light emitting diode is located at a side of the elastic member and emits light to the keycap. The light guide plate is disposed on the membrane circuit board. The light guide plate has a slot hole for containing the light emitting diode and has a hole corresponding to the elastic member. An optical microstructure is formed on the light guide plate for guiding light of the light emitting diode to be incident to the keycap. The elastic member passes through the hole to be disposed on the membrane circuit board.