Abstract: A variable capacitor includes: a dielectric sheet disposed on a substrate and covering an electrode pattern on the substrate; a resilient conductive supporting seat mounted on the dielectric sheet for supporting an insulating operating cap on a central portion thereof; a conductive cover body covering the conductive supporting seat and permitting the operating cap to extend outward; and a biasing member for biasing the central portion of the conductive supporting seat to move away from the substrate. The cover body is connected electrically to the conductive supporting seat and a conductive contact on the substrate. When the operating cap is depressed, the operating cap forces a contact portion of the conductive supporting seat to deform such that a surface area of the deformed contact portion that contacts the dielectric sheet is increased, thereby changing the capacitance between the conductive supporting seat and the electrode pattern.

Abstract: A variable capacitor includes: a dielectric sheet disposed on a substrate and covering an electrode pattern on the substrate; a resilient conductive supporting seat mounted on the dielectric sheet for supporting an insulating operating cap on a central portion thereof; a conductive cover body covering the conductive supporting seat and permitting the operating cap to extend outward; and a biasing member for biasing the central portion of the conductive supporting seat to move away from the substrate. The cover body is connected electrically to the conductive supporting seat and a conductive contact on the substrate. When the operating cap is depressed, the operating cap forces a contact portion of the conductive supporting seat to deform such that a surface area of the deformed contact portion that contacts the dielectric sheet is increased, thereby changing the capacitance between the conductive supporting seat and the electrode pattern.