Ultrasonic TFM with calculated angle beams

A matrix capture and total focusing method (TFM) ultrasound inspection system comprising:

• at least one ultrasonic array probe ultrasonically coupled to a test surface of a test object, the probe configured to transmit ultrasonic energy and to receive response energy from the test object;
• an acquisition unit causing sequential pulsing of N transmitters of the at least one probe and receiving response signals from M receivers of the at least one probe, the acquisition unit thereby acquiring a received matrix of response A-scans, Aij, wherein each response A-scan is the received response signals as a function of time, the received response signals being corresponding to transmission from an ith transmitter and reception at a jth receiver;
• and,
• an A-scan calculator configured to process the response signals and to calculate a calculated A-scan for a plurality of focal points along a desired propagation line within the test object, the propagation line at an angle θ relative to a test surface normal, and the plurality focal points located on the propagation line at different depths below the test surface, the A-scan calculator comprising:
• a delay calculator configured to calculate focal point delay times τij from the ith transmitter to the jth receiver via a focal point of the plurality focal points;
• and,
• a summation unit configured to calculate an A-scan beam forming amplitude at the focal point of the plurality focal points by making a summation of the response A-scans, wherein each response A-scan in the summation is delayed by the corresponding focal point delay time, the summation unit further configured to derive the calculated A-scan based on the A-scan beam forming amplitudes corresponding to each of the corresponding focal points along the propagation line;
• and,
• an image generator configured to generate and display an image based on the calculated A-scan.