Defect Imaging by Micromachined Ultrasonic Air Transducers

dynamic ranges in excess of 100 dB are attainable in pulseecho operation using commercially available discrete mmponents. Transmission experiments through aluminum and composite plates verify more than 100 dB dynamic range and demonstrate the ability of cMUTs to image defects in air at 2.5 MHz. W e also present a variation on cMUT design which improves the useful bandwidth of the device, permitting greater depth resolution in pulse-echo imaging.