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42 Cards in this Set
- Front
- Back
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Of transducer parts which has the greatest impedance |
Pzt Crystal |
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Duration event associated with narrow bandwidth |
Long |
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PCT thickness needed to create pulses with higher frequencies |
Thin |
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Percentage of intensity that is reflected when the sound beam strikes a boundary between two mediums |
IRC Intensity reflection coefficient |
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Bandwidth used with imaging transducers? |
Wide |
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Q factor associated with imaging probe? |
Low |
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Relationship between speed of sound in pzt and the frequency of sound |
Directly related |
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What does Snell's law predict regarding the refracted beam |
Angle |
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Bandwidth used with non Imaging transducers |
Narrow, High Q factor Main frequency / bandwidth |
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Percent of intensity that passes in a forward Direction when the beam strikes an interface between two media |
ITC |
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The angle of incidence other than 90° |
Oblique |
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What determines axial resolution |
Spatial pulse length |
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Process of heating the PCT Crystal to the Curie point during Manufacturing |
Polarization |
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Which part of the transducer is 1/4 wavelength thickness |
Matching layer |
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What is needed for refraction to occur |
~ Different speed of sound ~ oblique incident |
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This has an impedance greater than that of the skin |
Gel |
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Transmission with a Bend |
Refraction |
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Another mnemonic for axial |
Image |
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Events that are associated with wide bandwidth |
Short-duration events |
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PCT thickness needed to create pulses with low frequency |
Thick |
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Impedance def |
The acoustic resistance to sound traveling in a medium. |
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Impedance formula |
Z = pc |
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Impedance / density relationship |
Directly related |
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What angle is needed for normal incidence |
90° |
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What is the estimated reflection percentage of the intensity between a tissue - air interface Soft tissue - soft tissue Bone - soft tissue |
~ 99% ~ 01% ~ 10% - 60% |
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What does Snell's law predict |
The direction of the transmitted beam |
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ITC, intensity transmission coefficient |
Percentage of intensity that passes in a forward Direction |
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IRC, intensity reflection coefficient |
Percentage of intensity that bounces back |
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Interface with few degrees of refraction |
~ Soft tissue - fat interface ~ muscle - blood ~ soft tissue - fluid |
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Refraction definition |
A change in direction of wave propagation when traveling from one medium to another |
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. |
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Identify deep vs. Shallow PRP |
~ Deep equals long PRP. ~ Shallow equals short PRP. ~ PRP and depth are directly related |
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Pulse repetition frequency formula |
PRF = 77,000 (cm/s) / image depth (cm) |
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Identify parts |
A. Case B. Shield C. Insulator D. Matching layer E. PZT F. Backing material G. Wire |
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Which type of transducer depends on electric current to produce a frequency |
Continuous wave transducer |
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How is pzt Crystal thickness and frequency related |
Inversely |
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How does PZT thickness relate to wavelength |
~ Thin PZT = short wavelength Higher frequency ~ thick PZT = longer-wavelength Lower frequency |
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Define bandwidth |
A range of frequencies within a band |
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What is necessary for refraction to occur |
There must be a difference in impedance |
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What is PRP directly related to |
Maximum image death |
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PRF and max image depth relationship |
Inversely |
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Q-factor / pulse length relationship |
Directly |
