Method and device for improving the sensitivity and the signal to noise ratio of piezo-electric transducers having a plurality of sensors combined in parallel

摘要

A method and device are provided for improving the sensitivity and signal to noise ratio of transducers including several piezo-electric sensors interconnected in parallel to the input of an electric charge amplifier, said process consisting essentially in reducing the electric capacity of the combination of parallel sensors at the input of the amplifier so as to reduce the amplification gain applied to the noise without changing that which is applied to the signals picked up. This operation is achieved by means of an impedance transformer or else by means of at least one charge transfer capacitor connected by at least one switch alternately to the sensors and to the capacitor of the amplifier.