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Flashcards in Transducers & Beams Deck (49):
1

Aperature

Size of transducer element or group of elements.

2

Apodization

No uniform driving of elements in an array to reduce grating lobes.

3

Array

A transducer assembly containing several piezoelectric elements.

4

Axial

In the direction of the transducer axis. Parallel.

5

Axial Resolution

The minimum reflector separation along the sound path that is required to produce separate echoes.

6

Beam

Region containing continuous wave sound; region through which a should pulse propagates.

7

Composite

Combination of piezoelectric ceramic & non piezoelectric.

8

Convex Array

Curved linear array.

9

Crystal

Element.

10

Curie Point

Temperature at which an element material loses it's piezoelectric properties.

11

Damping

Materials attached to the rear face of a transducer element to reduce pulse duration; the process of pulse duration reduction.

12

Detail Resolution

The ability to image fine details and to distinguish closely spaced reflectors.

13

Disk

A thin, flat, circular object.

14

Dynamic Aperture

Aperture that increases with increasing focal length (to maintain constant focal width.)

15

Element

The piezoelectric component of a transducer assembly.

16

Elevational Resolution

The detail resolution in the direction perpendicular to the scan plane. It is equal to the section thickness and is the source of section thickness artifact.

17

Far Zone

The region of a sound beam in which the beam diameter increases as the distance from the transducer increases. FAR FIELD.

18

Focal Length

Distance from a focused transducer to the center of a focal region or to the location of the spatial peak intensity.

19

Focal Region

Region of minimum beam diameter and area.

20

Focal Zone

Length of the focal region.

21

Focus

The concentration of a sound beam into a smaller beam area that wouldn't exist otherwise.

22

Grating Lobes

Additional waker beams of sound traveling out in direction different from the primary beam as a result of the multi element structure of a transducer's arrays.

23

Lateral

Perpendicular to the direction of sound travel.

24

Lateral Resolution

Minimum reflector separation perpendicular to the sound path that is required to produce separate echoes.

25

Lead Zirconate Titanate

A ceramic piezoelectric material. PZT

26

Lens

A curved material that focusses a sound or light beam.

27

Linear

Adjectival form of line.

28

Linear Array

Array made of rectangular elements arranged in a line.

29

Linear Phased Array

Linear array operated by applying voltage pulses to all elements, but with small time differences to direct ultrasound pulses out in a various direction.

30

Linear Sequenced Array

Linear array operated by applying voltage pulses to groups of element sequentially.

31

Matching Layer

Material attached to the front face of a transducer elements to reduce the reflection a the transducer surface.

32

Natural Focus

The narrowing of a sound beam that occurs with an unfocused flat transduce element.

33

Near Zone

The region of a sound beam in which the beam diameter decreases as the diastase from the transducer increases. NEAR FIELD.

34

Operation Frequency

Preferred (max efficiency) frequency of operating a transducer.

35

Phased Array

An array that steers and focuses the beam electrically (with short time delay).

36

Phased Linear Array

Linear Sequenced array with phased focusing added; linear sequenced array with phased steering of pulses to produce a parallelogram shaped display.

37

Piezoelectricity

Conversion of pressure to electric voltage.

38

Probe

Transducer assembly

39

Resonance Frequency

Operational frequency

40

Scanhead

Transducer assembly

41

Sector

A geometric figure bounded by two radii and the arc of the circle included between them.

42

Sensitivity

Ability of an imaging system to detect t weak echoes.

43

Side Lobes

Weaker beam of sound traveling out from a since element in directions from those of the primary beam.

44

Sound Beam

The region of a medium that contains virtually all of the sound produced by a transducer.

45

Source

An emitter of ultrasound; transducer.

46

Transducer

A device that converts energy from one to another

47

Transducer Assembly

Transducer elements with damping and matching materials assembled in a case.

48

Ultrasound Transducer

A device that converts electric energy to ultrasound energy and vice versa.

49

Vector Array

Linear sequenced array that emits pulses from different starting points in different directions.