PURPOSE: To form electrodes in plural arrays crossing both main surfaces of a piezoelectric body and to form a matrix tape probe which improves sound field characteristics without any mutual interference of a piezoelectric part that electrodes cross each other by specifying thickness-directional and horizontal Young's moduli.

CONSTITUTION: The thickness Young's modulus of the piezoelectric body which has plural arrays of electrodes formed on both main surfaces is set to about five times as large as the horizontal Young's modulus to regard this element as one independent unit vibrator without any mutual interference of piezoelectric plate parts where electrodes cross on both main surfaces. Namely, the piezoelectric body uses a high polymer piezoelectric material and a compound piezoelectric material. For example, the piezoelectric body 9 uses the high polymer piezoelectric material such as polyvinylidene fluoride. Therefore, unnecessary vibration generated at the periphery of electrodes of the unit vibrator having electrodes 10a and 11a as a cross electrode is reduced.