Aiming at the problem of accurate identification of delamination defects of composite laminates, an optimization method of activation aperture of phased array ultrasonic testing was proposed by simulation and experiment, and the effects of the activation aperture on the acoustic field characteristics and detection results at different focusing depths were studied and analyzed. Firstly, for the phase array ultrasonic contact testing method, the multipoint source 3D acoustic field model under the solid-solid interfa…