Capacitive proximity sensor and door handle device comprising the capacitive proximity sensor

摘要

In a state in which a high-frequency signal at a first detection frequency f₁ is input to an LCR resonance circuit 20, upon detecting that a voltage signal S₁ is greater than or equal to an upper-limit threshold value V_th11 or less than or equal to a first lower-limit threshold value V_th12, a high-frequency signal at a second detection frequency f₂ is input to the LCR resonance circuit 20. Then, in a state in which the high-frequency signal at the second detection frequency f₂ is input, the proximity of a human body or water to a sensor electrode 22 is detected by detecting that the voltage signal has reached less than or equal to a second lower-limit threshold value V_th21.