Chapter 12 - System Safety and Maintenance
Relationship of Index to Display Accuracy
Terason t3000 / Echo Ultrasound System User Guide
278
TISunsc-A>1
= 16.2%
TIBunsc
= 7.7%
TIC
= 10.2%
Relationship of Index to Display Accuracy
The discussion above concerns the relationship between the calculated index value
(x
Calc.
), and the “true” value (x
Actual
), which would be obtained under conditions without
measurement uncertainty. Display precision is the relationship between the displayed
index value (x
Display
) and (x
Calc
). The displayed values (shown in reverse video along with
the corresponding labels) may take on the following values (where
x
indicates the actual
calculated index value (x
Calc
.)
Display Precision of TI Values
The following table indicates the precision of the display for TI values.
Display Precision of MI Values
The following table indicates the precision of the display for MI values.
TI Value Precision
Range of calculated
value x
Calc.
Displayed value
x
Display
x < 0.4
<0.4
0.4
x < 0.5
0.4
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
1.9
x < 2.25
2.0
2.25
x < 2.75
2.5
2.75
x < 3.25
3.0
Etc.
Etc.
MI Value Display Precision
Range of calculated
value x
Calc.
Displayed value
x
Display
x < 0.4
< 0.4
0.4
x < 0.5
0.4