PRESENCE DETECTION BY MEANS OF A CAPACITIVE SENSOR

摘要

The invention relates to a presence detector (1) of the capacitive type, comprising at least one detector electrode (3), forming part of a capacitor (5), the capacitance (Cx) of which will vary with the approach of an object or part of the body of a user and a charging unit (9) for the capacitor applying cycles of charge to said capacitor (5). The sensor further comprises means (11) for the measurement of a parameter, the variation of which reflects a variation in the charging current for the capacitor (5) and, connected to said measuring means (11), an extraction unit (13) for said parameter, for determination of a change in the capacitance of the capacitor (5) from the variation in said parameter between the successive cycles of charging the capacitor, following an approach of an object or a part of the body of a user.