Chapter 12 - System Safety and Maintenance
Relationship of Index to Display Accuracy
Terason t3000 / Echo Ultrasound System User Guide
279
When the effects of calculation errors are combined with the effects of display precision,
overall Display Accuracy can be defined as follows:
The following table lists the values of Display Accuracy that are estimated to occur with the
Terason Ultrasound System. These values of Display Accuracy are given in conjunction
with the values of relevant indices that may be displayed with transducers available with the
system.
Items in the following table correspond to index values actually displayed with the
Terason Ultrasound System. For those indices for which no values are displayed, all
calculated values of the index are less than 1.0 when the given index is considered relevant
to the operating mode and possible intended use of the transducer.
0.5
x < 0.7
0.6
0.7
x < 0.9
0.8
0.9
x < 1.1
1.0
1.1
x < 1.3
1.2
1.3
x < 1.5
1.4
1.5
x < 1.7
1.6
1.7
x < 1.9
1.8
x = 1.9
1.9
Estimated Display Accuracy Values
Display
Value
MI
TIS
scan
TIS
unsc-A<1
TIS
unscA>1
TIB
unsc
TIC
<0.4
(a)
(b)
(a)
(b)
(a)
(b)
(a)
(b)
(a)
(b)
(a)
(b)
0.4
0% to –18%
0% to –18%
0% to –18%
0% to –18%
0% to –18%
0% to –18%
0.6
20% to –13%
20% to –13%
20% to –13%
20% to –13%
20% to –13%
20% to –13%
0.8
14% to –10%
14% to –10%
14% to –10%
14% to –10%
14% to –10%
14% to –10%
1.0
11% to –8%
11% to –19%
11% to –19%
11% to –19%
11% to –19%
11% to –19%
1.2
9% to –7%
1.4
8% to –6%
1.5
20% to –14%
20% to –14%
20% to –14%
20% to –14%
20% to –14%
1.6
7% to –5%
1.8
6% to –10%
2.0
(c)
14% to –11%
14% to –11%
14% to –11%
14% to –11%
14% to –11%
2.5
3.0
33% to –14%
33% to –14%
33% to –14%
33% to –14%
33% to –14%
MI Value Display Precision (Continued)
Range of calculated
value x
Calc.
Displayed value
x
Display
DisplayAccuracy
xDisplay xActual
–
xActual
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