A transducer array (32) including a support member (322), an inner surface of which is defined by a quadric surface of revolution (45) formed by rotating an imaginary quadratic curve (41, 42, 43, 44) about an imaginary rotation axis (46), the inner surface provided with a plurality of openings (40), and a plurality of transducers (321) including receiving surfaces (10) having a substantially parallelogram shape so as to confirm with the openings. In the receiving surface, one vertex among four vertexes (vr1, vr2, vr3, vr4) is proximate with the imaginary rotation axis than the other three vertexes.
