Abstract <p>Acoustic testing using guided waves, in particular Lamb waves, is an effective tool for flaw detection in thin test objects. This work considers the implementation of ultrasonic testing using Lamb waves and digitally focused antenna array technology (DFA). The use of high-frequency Lamb waves, excited using wedges, makes it possible to implement ultrasonic testing using conventional equipment. To improve the quality of the restored acoustic images, a combined digital coherent processing is proposed, integrating the standard DFA technology algorithm and the Phase Coherence Imaging (PCI) method. Experimental results confirm that this approach ensures the restoration of defect images at various depths with a high signal-to-noise ratio, demonstrating its potential for ultrasonic testing of thin-walled structures using the pulse-echo method and expanding the capabilities of using phased array flaw detectors.</p>