Ultraäänipää

Ultraäänipää, or ultrasonic transducer in English, is a crucial component in ultrasound technology. It is a device that converts electrical energy into ultrasonic waves and vice versa. This transformation is typically achieved through piezoelectric crystals, which exhibit the piezoelectric effect. When an electrical voltage is applied to these crystals, they vibrate and generate high-frequency sound waves, far beyond the range of human hearing. Conversely, when these sound waves strike the crystals, they produce a small electrical voltage.

In medical ultrasound, the transducer acts as both the transmitter and receiver of sound waves. During imaging, the transducer emits short bursts of ultrasound pulses into the body. These sound waves travel through tissues and reflect off different structures. The reflected waves, or echoes, return to the transducer, which then converts them back into electrical signals. These signals are processed by an ultrasound machine to create an image of the internal organs and tissues.

Ultrasonic transducers vary in frequency and design depending on their intended application. Higher frequency transducers generally provide better resolution but have a shallower penetration depth, making them suitable for imaging superficial structures like small parts or the thyroid. Lower frequency transducers penetrate deeper into the body, making them ideal for abdominal or obstetric imaging. The shape and arrangement of the piezoelectric crystals within the transducer also influence the ultrasound beam's focus and direction. Transducers can be convex, linear, or phased array, each offering distinct imaging capabilities.