as it is often difficult for users of a keyboard to adequately identify and select the correct keys in a keyboard where the light is inadequate , it is desirable to provide a keyboard capable that allows a user to better see keys of the keyboard even in environments where there is not sufficient light to see the keys . a keyboard of the present invention comprises a substrate , a membrane , an elastic member , a cover sheet , a keytop , and light - emitting means for emitting light from the bottom of the substrate to the keytop . the keytop is illuminated and a legend on a key surface can be seen , so that the chance of incorrect key stroke is reduced .