Physics 111

Question 1

the diameter of the piezoelectric element(s) producing the beam

Answer 1

Aperture

Question 2

the transducer with multiple active elements

Answer 2

Array

Question 3

same as real-time ultrasound

Answer 3

Automatic Scanning

Question 4

the ability to accurately identify reflectors that are arranged parallel to the ultrasound beam

Answer 4

Axial resolution

Question 5

the damping material of the transducer assembly, which reduces the number of cycles produced in a pulse

Answer 5

Backing material

Question 6

the range of frequencies present within the beam

Answer 6

Bandwidth

Question 7

occurs when in-phase waves meet; the amplitudes of the two waves are added to form one large wave

Answer 7

Constructive Interference

Question 8

ability to differentiate one shade the of gray from another

Answer 8

Contrast resolution

Question 9

a synonym for the active element of the transducer, the piezoelectric part of the transducer assembly that produces sound

Answer 9

Crystal

Question 10

piezoelectric properties the temperature at which an ultrasound transducer will gain its, and also the temperature at which a transducer will lose the ability to produce sound if heated again above this temperature

Answer 10

Curie point

Question 11

the transducer commonly referred to as a curvilinear or convex probe

Answer 11

Curved sequenced array

Question 12

the process of reducing the number of cycles of each pulse in order to improve axial resolution

Answer 12

Damping

Question 13

same as backing material; the part of transducer assembly that reduces the number of cycles produced in a pulse

Answer 13

Damping material

Question 14

the inability to determine the depth of the reflector if the pulses are sent out too fast for them to be timed

Answer 14

Depth ambiguity

Question 15

occurs when out-of-phase waves meet; the amplitude of the resultant wave is smaller than either of the original waves

Answer 15

Destructive Interference

Question 16

spreading of the beam that occurs in the far zone

Answer 16

Divergence

Question 17

the piezoelectric part of the transducer assembly that produces sound

Answer 17

Element

Question 18

the third dimension of the beam

Answer 18

Elevational plane

Question 19

the resolution in the third dimension of the beam; the slice-thickness plane

Answer 19

Elevational resolution

Question 20

the diverging part of the beam distal to the focal point

Answer 20

Far zone

Question 21

the area of the beam with the smallest beam diameter

Answer 21

Focal point

Question 22

the portion of the transducer that is in contact with the patient’s skin

Answer 22

Footprint

Question 23

three-dimensional ultrasound in real time

Answer 23

Four-dimensional ultrasound

Question 24

one complete ultrasound image

Answer 24

Frame

Question 25

the number of frames per second

Answer 25

Frame rate

Question 26

the diverging part of the beam distal to the focal point

Answer 26

Fraunhofer zone

Question 27

the number of cycles per second

Answer 27

Frequency

Question 28

the part of the beam between the element and the focal point

Answer 28

Fresnel zone

Question 29

states that waves are the result of the interference of many wavelets produced at the face of the transducer

Answer 29

Huygen's principle

Question 30

waves whose peaks and troughs overlap

Answer 30

In-phase

Question 31

the ability to accurately identify reflectors that are arranged perpendicular to the ultrasound beam

Answer 31

Lateral resolution

Question 32

the man-made ceramic of which many transducer elements are made; abbreviated PZT

Answer 32

Lead zirconate titanate

Question 33

the transducer commonly referred to as the linear probe or transducer

Answer 33

Linear sequenced array

Question 34

the component of the transducer that is used to step down the impedance from that of the element to that of the patient’s skin

Answer 34

Matching layer

Question 35

transducer that acquires real-time volumes using up to 10,000 elements, compared to the 128 to 512 elements used in standard 1D array transducers

Answer 35

Matrix array transducer

Question 36

transducers with a motor for steering the beam

Answer 36

Mechanical scanheads

Question 37

the part of the beam between the element and the focal point

Answer 37

Near zone

Question 38

the length of the region from the transducer face to the focal point

Answer 38

Near-zone length

Question 39

waves that are 180° opposite each other; the peak of one wave overlaps the trough of the other and vice versa

Answer 39

out-of-phase

Question 40

the transducer that uses phasing, or small time differences, to steer and focus the beam

Answer 40

Phased array

Question 41

the method of focusing and/or steering the beam by applying electrical impulses to the piezoelectric elements with small time differences between shocks

Answer 41

Phasing

Question 42

the ability to convert pressure into electricity and electricity into pressure

Answer 42

Piezoelectric

Question 43

a measure of beam purity; the operating frequency of the transducer divided by the bandwidth

Answer 43

Quality factor (Q-factor)

Question 44

the ability to determine how far away a reflector is so it can be displayed on the screen; without range resolution there is depth ambiguity

Answer 44

Range resolution

Question 45

live ultrasound, also known as automatic scanning

Answer 45

Real time

Question 46

to alternatively expand and contract

Answer 46

Resonate

Question 47

created when one or more pulses of sound return from the tissue containing information related to the depth and amplitude of the reflectors

Answer 47

Scan lines

Question 48

the third dimension of the beam

Answer 48

Section-thickness plane

Question 49

the ability of a system to display low-level or weak echoes

Answer 49

Sensitivity

Question 50

the third dimension of the beam

Answer 50

Slice-thickness plane

Question 51

the length of the pulse

Answer 51

Spatial pulse length

Question 52

the ability of the system to distinguish between closely spaced objects; refers to axial, lateral, contrast, and elevational resolution

Answer 52

Spatial resolution

Question 53

allows the user to see width, height, and depth; may also be referred to as volume scanning

Answer 53

Three-dimensional ultrasound

Question 54

ability to display moving structures in real time; also known as frame rate

Answer 54

Temporal resolution

Question 55

any device that converts one form of energy into another; may also refer to the part of the ultrasound machine that produces sound

Answer 55

Transducer

Question 56

component of the backing material

Answer 56

Tungsten

Question 57

the leading edge of a wave which is perpendicular to the direction of the propagating wave; formed as a result of Huygen’s principle

Answer 57

Wavefront

Question 58

a small wave created as a result of Huygen’s principle

Answer 58

Wavelet