Abstract: A sensor unit for picking up mechanical vibrations, sound and ultrasound has at least one piezoelectric foil strip (piezo strip) as a sensor element. The piezo strip has signal wires attached thereto for transporting out electrical signals representing vibration, sound or ultrasound that have been picked up. The piezo strip is, at two opposite ends, attached to flat support parts, and at least one engagement strip of for instance plastic material is attached in the same support parts to extend in curved-out fashion along the piezo strip, thereby to provide at least one space between the strips. Several sensor units can be mounted together in a frame to constitute a sheet with a sensor matrix.

Abstract: A sensor (10) preferably for use in an electronic stethoscope (15) comprises a substantially cylindrically shaped viscoelastic contact and transfer body (2) engaging tightly a hard back piece (1) and being tightly surrounded by a piezoelectric member, e.g. one or two piezoelectric foils (4, 7) that convert sound pressure to electrical signals.