A variable capacitance element of the invention includes: a columnar
vibrator formed inside a cylindrical hole of a supporting wall; a first
circular driving electrode disposed above the columnar vibrator; a first
circular capacitive electrode disposed in the middle of the columnar
vibrator; a second circular driving electrode disposed on the periphery
of the cylindrical hole of the supporting wall; and a second circular
capacitive electrode disposed on an inner side surface of the supporting
wall. An electrostatic force is increased or decreased sequentially in
the circumferential direction of the second driving electrode that is
divided into four parts by sequentially increasing or decreasing the
driving voltage in the circumferential direction of the second driving
electrode. As a result, the columnar vibrator is rotated to change the
electrostatic capacitance between the first capacitive electrode and the
second capacitive electrode.