Transducers used for the real-time mode are different than for the A-mode, B-, or M-modes. A linear array transducer with multiple piezoelectric crystal elements that are different arranged and fired, transmits the needed larger sound beam.
A subgroup of x adjacent elements (8-16; or more in wide-aperture designs) is pulsed simultaneously; the inner elements pulse delayed with respect to the outer elements. The interference of the x small divergent wavelets generates a focused beam. The delay time determining the focus depth of a real-time transducer can be changed during imaging.
Similar delay factors applied during the receiving phase, result in a dynamic focusing effect on the return. This forms a single scan line in the real-time image. To produce the following scan line, another group of x elements is selected by shifting one element position along the transducer array from the previous group. This pattern is then repeated for the groups along the array, in a sequential and repetitive way.

The reflector is a stationary plate component of a flowprobe used in Doppler ultrasound. Each transducer alternately emits an ultrasound beam which is reflected from this reflector to the receiving transducer. The fixed distance of the reflective pathway is critical to the measurement of the ultrasonic transit time and the accurate measurement of volume flow.

See also Target Strength.

Different sound velocities in tissue are causing refraction artifacts. With convex elastomer lens transducers, sound beam refraction at the skin interface can alter the transducer's focusing characteristics and beam profile, cause element to element nonuniformity, and cause phase changes in the acoustic wave. These cumulative refraction induced errors degrade the image quality through distortion and loss of resolution. Because the amount of refraction is proportional to the velocity mismatch, the greater the mismatch, the greater the refraction.

Retrolenticular afterglow could occur through diffraction and refraction on interfaces. A circular object may act as a lens to the ultrasound beam, showing an artifact region of increased echogenicity.

Shear Waves are waves that travel perpendicular to the direction of the sound beam. During an ultrasound examination, shear waves are generated and transmitted into the body using the ultrasound probe. These waves travel through the tissue and their speed of propagation is influenced by the tissue's stiffness. Softer tissues allow the shear waves to travel faster, while stiffer tissues slow them down.
By analyzing the speed of shear waves, ultrasound systems can provide quantitative measurements of tissue stiffness, known as shear wave elastography. This technique is particularly useful in assessing the stiffness of organs like the liver, breast, thyroid, and muscles.
Shear wave ultrasound elastography has various applications in clinical practice. For example, it can help identify liver fibrosis, a condition characterized by excessive scarring of the liver tissue. By measuring the liver's stiffness using shear waves, clinicians can assess the severity of fibrosis without the need for invasive procedures like liver biopsies.