TRANSDUCER TESTING IN ULTRASONIC INSPECTION.

Some transducer manufacturers have lead in the development of transducer characterization techniques have participated in developing the AIUM-E. 1065 standard Guide for evaluating characteristics of Ultrasonic search units.
Additionally, some manufacturers perform characterizations according to AWS, ESI, and many other industrial and military standards.often,equipment in test labs is maintained in compliance with MIL-C-45662A calibration system requirements. As part of the documentation process, an extensive database containing records of the waveform and spectrum of each transducer is maintained and can be accessed for comparative or statistical studies of transducer characteristics.
Manufacturers often provide time and frequency domain plots for each transducer. The signals below were generated by a spiked pulser. The waveform image on the shows the test response signal in the time domain (amplitude versus time). The spectrum image on the right shows the same signal in the frequency domain ( amplitude versus frequency).  The signal path is usually a reflection from the back wall ( fused silica)  with the reflection in the far field of the transducer.