Method and apparatus for testing a composite object, using tension waves

A method and apparatus for generating a tension wave, wherein a beam of coherent light (314, 522) is directed to an absorber surface (308, 508) defined by the walls of a channel (306, 506) extending into a transducer structure (300, 500), said channel (306, 506) either having the shape of a cone (506) or extending across a side of the transducer structure (300) and having a v-shaped cross section (306)). A compression wave (418, 420, 606, 608) is generated within the transducer structure (300, 500) and reflected on a reflecting surface (408, 410, 510) of the transducer structure (300, 500) to form the tension wave (424, 434, 610, 612). The tension wave (424, 434, 610, 612) is directed through a test object (304, 504) in a desired direction (434, 436, 614, 616) using a configuration of the reflecting surface (408, 410, 510) relative to the test object (304, 504).