Illuminated keyboard with optical switch

An illuminated keyboard with an optical switch, the illuminated keyboard comprising:

• a circuit board comprising plural light-emitting elements, plural light emitters and plural light receivers, wherein each light-emitting element emits a light beam, each light emitter emits a sensing light, and each light receiver generates an electronic signal when the sensing light from the corresponding light emitter is received by the light receiver;
• and
• plural keys located over the circuit board, wherein each key is aligned with the corresponding light-emitting element, the corresponding light emitter and the corresponding light receiver, and each key comprises:
• a keycap;
• a housing located under the keycap;
• a first reflective element disposed within the housing, wherein the sensing light is reflected by the first reflective element;
• a triggering post connected with the keycap and inserted into housing, wherein the triggering post is movable relative to the housing, and a second reflective element is connected with the triggering post, wherein after the sensing light from the first reflective element is received by the second reflective element, the sensing light is reflected to the light receiver by the second reflective element;
• a light guide element disposed within the housing and located over the light-emitting element;
• and
• a light guide frame disposed within the housing, wherein a top surface of the light guide frame is substantially at the same level with a top surface of the housing, and the light guide frame is connected with the light guide element and arranged around the triggering post,
• wherein after the light beam emitted by the light-emitting element is introduced into the housing, the light beam within the housing is guided to the light guide frame by the light guide element, and the light beam is scattered to a region around the triggering post and outputted from the keycap, wherein after the sensing light emitted by the light emitter is introduced into the housing and reflected to the second reflective element by the first reflective element, the sensing light is reflected to the light receiver by the second reflective element, so that the light receiver generates the electronic signal.