Inspecting Mounted Components and Bare Boards Acoustically

摘要

When an electronic component is being inspected by an acoustic microscope, ultrasound is pulsed into the part by the scanning transducer. At any material interface within the part, a portion of the ultrasound that has been pulsed into the part is reflected as an echo signal while the remainder travels deeper. Using the echo signals to create an acoustic image is known as reflection-mode imaging. Using the ultrasound that exits the far side of the part is known as transmission-mode imaging.