Patent ID: 7841791
Filing Date: 2010-11-30
Classification: G06F,H01H

Abstract:
1. A keyboard comprising: a substrate; a plurality of keytops arranged on the substrate, the keytops having optical transparency and liftably supported to the substrate; a membrane switch placed between the keytops and the substrate, the membrane switch having an electrically insulating membrane sheet on which a plurality of contacts operated by the keytops are formed; a light source mounted on the membrane sheet, the light source emitting light from an end part of the membrane sheet; a conductor pattern formed on the membrane sheet and configured to supply an electric current to the light source; a lightguide stacked on the membrane sheet the lightguide having an incident plane at an end facing the light source, and light from the light source incident on the incident plane passing through the lightguide; and a light-diffusing plate stacked on the lightguide, and through which light from the lightguide traveling toward the keytops penetrates, the light-diffusing plate having a light-diffusing part which diffuses light penetrating the lightguide across a wider range as the light travels away from the light source.