Abstract: An electrostatic capacitance type detecting device which includes a first electrode placed in the proximity of an object to be measured, a second electrode placed in the proximity of the first electrode, a film like dielectric member interposed between the first and the second electrodes, a first resistor one end of which is connected to one end of the first electrode, a second resistor one end of which is connected to one end of the second electrode, an a. c. signal generator connected to the other ends of the first and the second resistors and to the ground and a phase difference detecting means connected to the first and the second electrodes.

Abstract: Two capacitors (C1, C2) having an identical structure and equal capacitance are used in series connection for the detection of phase difference so that ambient temperature affects both the capacitors in a similar manner to compensate for the variation in electrostatic capacitance. The sensor according to one embodiment has a lamination structure that a detection capacitor (C1) is closely attached to a comparison capacitor (C2) providing a short time period for thermal equilibrium of both capacitors. According to another embodiment sensor, since lamination capacitors having identical structure and identical characteristic are electrically connected in series, it is now possible to locate both capacitors at desired points which are spaced apart. A member (34) having a high heat conductivity may be arranged in a space between both the capacitors to thereby reduce the time required for thermal equilibrium. In a pulse phase adjusting circuit used for processing an output signal from the sensor, a variable d.c.