HUMAN BODY DETECTOR

摘要

PROBLEM TO BE SOLVED: To provide a human body detector capable of distinguishing raindrops and a human body. SOLUTION: A detection circuit 36 for detecting a resonance voltage V1 is connected to a sensor resonance circuit 35 for modulating a constant frequency voltage corresponding to a change in the electrostatic capacitance of a sensor electrode 37. A differentiator 41 acquires a rateτof change by differentiating a detected voltage V2 with time and passes a voltage having a rateτof change equivalent to or higher than a prescribed valueτA is connected to the detection circuit 36. A high-pass filter(HPF) 42 for passing a voltage having a rateτof change equivalent to or higher thanτB is connected to the differentiator 41. A comparator 43 is connected to the HPF 42, and a power source 44 for impressing a reference voltage V4 to a non-inverted input terminal 43b of the comparator 43 is connected.