What type of signal does a fiber optics probe primarily use in ultrasonic testing?

In ultrasonic testing with a fiber optics probe, a pulsed signal is primarily used. This type of signal involves sending short bursts or "pulses" of ultrasonic waves into the material being tested. The use of pulsed signals is essential in ultrasonic testing because it allows for precise measurement of time intervals between the emission of the pulse and the receipt of the echo from any discontinuities or features within the material.

This time-of-flight measurement is crucial in determining the depth and location of flaws, as well as in characterizing the material properties. The fiber optics probe helps in delivering these pulsed ultrasonic signals efficiently, allowing for effective testing in various contexts, especially where electronic sensors may be compromised by the environment.

While analog and digital signals refer to the method of signal representation and processing, the continuity of the waves in continuous wave signals does not align with the conventional practices of ultrasonic testing, where discrete pulses provide the necessary information for analysis.