PROXIMITY SENSOR

摘要

Proximity sensor (10) for detecting the proximity of a conductive component (40) comprising an oscillator having electrical properties and arranged to provide an oscillating signal. First coil (20) arranged to receive the oscillating signal and alter the electrical properties of the oscillator by a first variation in response to the proximity of the conductive component to the proximity sensor. Second coil (30) arranged to receive the oscillating signal and alter the electrical properties of the oscillator by a second variation in response to the proximity of the conductive component (40) to the proximity sensor, wherein the first coil (20) and the second coil (30) cause a different variation to the electrical properties of the oscillator for the same proximity of the conductive component (40) to the proximity sensor (10). Proximity output arranged to provide a proximity signal which varies in dependence upon the proximity of the conductive component (40) to the proximity sensor and based on a comparison of the first variation to the second variation.