Proximity and contact sensor and sensor element

摘要

A proximity and contact sensor (10) is provided with a sensor element (11) and a detection circuit (16). The sensor element is provided with a matrix (13) in which coil-shaped carbon fibers (12) are dispersed. A high-frequency oscillation circuit (19) of the detection circuit (16) supplies the sensor element with a high-frequency signal. A detector (22) in the detection circuit (16) receives an output signal from the sensor element (11) and detects proximity of an object (24). In one example, the coil-shaped carbon fibers (12) are contained in the matrix by 1 to 20% by weight. In another example, a high-frequency oscillation circuit generates a high-frequency signal of 100 to 800 kHz.