Abstract: A curved bar probe (1) for an echograph is fabricated by using a thin support (2) on which is placed a bar of piezoelectric crystal. The bar is divided into a plurality of piezoelectric transducers elements (3). The thin support presents the particularity of being rigid at room temperature but is thermodeformable. By subjecting it to a heating-cooling cycle during which it is given a desired curved shape, a rigid bar having an imposed curved shape is obtained. It is then possible to avoid the adhesion of said support to a base (16). This would form a back-reflecting surface for acoustic waves and would create interference harmful to the useful acoustic signal.

Abstract: The electric connection between the control circuits (13,14) of a probe and the metallized faces (5,6) of the piezoelectric elements (2) of said probe is provided by metallizations (6,8) made on parts, support (1) or blade (4) in contact with said metallized faces. The mechanical and electric connection between said metallizations may be provided by a thin layer of conducting glue (19,20).

Abstract: In order to make a probe having a concave attack face, a continuous acoustic transition blade (5) is used. Said blade is metallized (7) and is common contact with all the front metallizations (6) of the piezoelectric elements of the probe. The rear metallizations (8) of the elements terminate electrically and independently backwards of the probe. As a result, the electric connection of the piezoelectric elements is simplified. Said probe is usable in experiments with ultrsounds where good focusing is desired.

Abstract: When making curved bar probes it is necessary, particularly at high frequency, to provide circuits for the connection of piezoelectric elements of the bars which are compatible with the curvature imposed to the bar after it has been fabricated flat. The invention overcomes such difficulty by adjoining on both sides of the elements a generally parallelepipedic relay metallized on at least two (12,13) of its adjacent faces to transpose one connection face (7) situated in plane which must be curved into one connection face (13) which is perpendicular and of which the orientation remains unchanged and parallel to a same plane during the curvature operation. As a result, the connection is simplified.