What is the purpose of gain adjustment in phased array systems?

The purpose of gain adjustment in phased array systems is to amplify received signals for better echo display. In phased array ultrasonic testing, the signals returned to the transducer from the tested material can vary widely in strength due to factors like distance, material properties, and geometric configurations. By adjusting the gain, operators can enhance the signals received, which ensures that the echoes displayed on the screen are more distinguishable and easier to interpret. This control over signal amplification helps in identifying flaws or features within the material being tested, leading to improved detection capabilities and overall inspection quality.

The other options do not accurately reflect the specific role of gain adjustment. For instance, gaining does not influence the speed of signal transmission—an aspect determined by the properties of the medium and the transducer. While it can indirectly affect resolution by making signals clearer, gain adjustment does not directly control the angle of the ultrasonic beam or enhance imaging software resolution. Thus, the focus of gain adjustment is primarily on the amplification of received signals to optimize visibility and interpretation of the data collected.