A row-column addressed micromachined ultrasonic transducer array for surface scanning applications

Area of Science:

• Ultrasonic Transducer Technology
• Non-Destructive Testing (NDT)
• Array Signal Processing

Background:

• Capacitive Micromachined Ultrasonic Transducer (CMUT) arrays are crucial for advanced imaging.
• Traditional N by N fully addressed 2-D arrays require extensive electronic components.
• Efficient addressing schemes are needed to reduce complexity and cost in ultrasonic NDT.

Purpose of the Study:

• To analyze and demonstrate the efficacy of row-column addressed arrays for ultrasonic NDT.
• To present simulation and experimental results of a 32x32 CMUT array using this addressing scheme.
• To evaluate the performance of row-column addressing as an alternative to full addressing in 2-D arrays.

Main Methods:

• A 32x32 CMUT array with a center frequency of 5.3MHz was utilized.
• The array was employed for C-scan imaging of test objects with 1.0mm and 0.5mm diameter holes.
• Simulation and experimental data were collected and analyzed.

Main Results:

• The row-column addressed CMUT array successfully performed C-scans, detecting small defects.
• This addressing scheme requires significantly fewer interconnections and electronic components (N vs. N^2) compared to full addressing.
• The aperture size (4.8mm x 4.8mm) limited the field of view, but the principle was validated.

Conclusions:

• Row-column addressed arrays present a viable and more economical alternative for 2-D ultrasonic NDT.
• The reduced electronic complexity makes this scheme attractive for practical NDT implementations.
• Further research can explore optimizing aperture size and addressing schemes for broader NDT applications.