Untitled Flashcards

Front

The job of the damping material in the transducer:

Back

damping reduces sensitivity (Ch.8)

Front

The damping material in a transducer improves what type of the system's resolution?

Back

longitudinal resolution (axial)

Front

The acoustic impedance of the matching layer is ___________ the acoustic impedance of skin

Back

Impedance of the matching layer is greater than of the skin (Ch.8)

*Know the order of the impedance of different materials

Front

How thick are the Active Element and Matching Layer of a transducer?

Back

1/2 and 1/4 of the wavelength thick respectively

Front

List the components of the Transducer (there's how many)?

Back

Case, electric shield, acoustic insulator, PZT/element, wire, matching layer, backing/damping material.

Front

Which of the following crystals will produce sound with the lowest frequency?
a. thin and with low speed
b. thin with high speed
c. thick with low speed
d. thick with high speed

Back

Thick with low speed. (Ch.8)

*know how element thickness/diameter relate to frequency and focus depth etc.

Front

Which type of transducer has more backing material? therapeutic or imaging?

Back

imaging (ch8)

*what about continuous wave transducers and backing material?

Front

Which of the following probes creates a beam with the deepest focus?
a. 4mm diameter, 4 MHz
b. 6mm diameter, 8 MHz
c. 6mm diameter, 2 MHz
d. 5mm diameter, 8 MHz

Back

b. 6mm diameter, 8 MHz. Longer focal lengths are associated with large diameter, high freq probes. (Ch.9)

Front

Transducer frequency and near zone length are inversely related?

Back

False (Ch.9)

*know your relationships

Front

A pair of 9 mm diameter probes are identical except for frequencies, which are 3 mhz and 6 mhz. which sound beam will spread out more in the far field.

Back

3 mhz. Beams are more compact as freq increases (Ch.9)