Sense Capacitor for Capacitive Keyboards
Original Publication Date: 1981-Jun-01
Included in the Prior Art Database: 2005-Feb-11
Capacitance keyboards are often exposed to relatively large changes in capacitance resulting from small contaminating particles between the capacitive plate members. As a result, it is desirable to have a key-board sensing capacitor which is able to change its capacitance at relatively large air gap separation distances to overcome the effect of small contaminating particles separating the plates.