What is the primary function of the ultrasound transducer?

• A. Generates ultrasound waves and detects waves reflected off structures
• B. Amplifies electrical signals from the transducer
• C. Filters noise from the received signal
• D. Converts electrical energy into heat

Answer: (A)

The transducer is the device that both sends and receives the ultrasound signals. It uses piezoelectric crystals to convert electrical energy into mechanical vibrations that generate ultrasound waves, and then, when those waves bounce back from tissues, the same crystals convert the returned mechanical energy back into electrical signals. This pulse-echo process is the core of how ultrasound creates an image. Amplification of the resulting signal, filtering to reduce noise, and other processing happen afterward in separate parts of the system, not at the transducer itself. Heating would not be a desired or primary function, since the transducer is designed to efficiently convert electrical energy into sound, not into heat.