1-5
What is the shape of the element in an annular phased array transducer?
Circular
Which of the following transducers creates a rectangular-shaped image?
Linear phased array
Annular phased array
Linear sequential array
Mechanical array
Linear sequential array
What statement best describes the transducer's sound beam? (Image "^ to the left")
Focused, unsteered
Focused, steered to the right
Unfocused, unsteered
Focused, steered to the left
Focused, steered to the right
What happens to the image if there is a damaged PZT crystal in a mechanical transducer?
Entire image is lost
How are the piezoelectric crystals excited in a sequential linear array transducer?
In small groups in a specific order
What transducer most likely created this 2D image? (Image)
Vector
What happens to the image if there is a damaged PZT crystal in an annular array transducer?
Horizontal dropout
What statement best describes the transducer's sound beam? (Image "∨")
Focused, unsteered
Focused, steered to the right
Defocused, unsteered
Focused, steered to the left
Defocused, unsteered
What transducer uses a target-shaped crystal that creates a beam that is always focused in all planes and at all depths?
Annular phased array
What type of artifact occurs while using an array transducer that diminishes image quality by degrading lateral resolution?
Grating lobes
What term describes the ability of an imaging system to accurately display a sonographic image?
Resolution
The process of electrical steering by electronically transmitting sound beams in different directions without the use of moving parts is known as:
Phasing
A curved pattern of electrical spikes creates a _____ sound beam during transmission.
Focused
What post-processing effect takes an image from 3D data and produces an element of realism to the image?
Rendering
Which statement best describes the elements in a linear phased array transducer?
Squares, 1/2 wavelength thick
Rectangular shaped, 1/4 to 1/2 wavelength wide
Ring-shaped with common center
Coin-shaped
Rectangular shaped, 1/4 to 1/2 wavelength wide
This frozen image shows a: (Image)
Which of the following transducers is best described as mechanically steered, and has a fixed, single focus?
Linear phased
Mechanical
Linear sequential
Curved array
Mechanical
Active elements arranged in a bowed or arched line are called:
Convex
How many active elements are in a mechanical transducer?
1
The excitation of array elements with dissimilar electrical voltages is called _____ and is used to _____.
Apodization; eliminate lobes
What is responsible for creating the electrical spike patterns?
Beam Former
A single slab of PZT that is cut into a collection of separate pieces is called a(n):
Array
What type of transducer experiences erratic steering and focusing when a PZT crystal becomes damaged?
Phase arrays
What statement best describes the transducer's sound beam? (Image "\")
Focused, steered to the left
Unfocused, steered to the right
Unfocused, steered to the left
Focused, steered to the right
Unfocused, steered to the left
In a transducer with a disc-shaped crystal, which of the following statements is true?
Elevational resolution is unrelated to lateral resolution
Elevational resolution equals 1/2 of the sound beam's width
Elevational resolution equals lateral resolution
Elevational resolution equals 1/4 of the sound beam's width
Elevational resolution equals lateral resolution