GE Logiq 500, Advanced Reference Manual, Page: 290 / 474

FDA Acoustic Output Data
LOGIQ 500 Advanced Reference Manual
2276614–100 Rev. 0
6–106

Key to Tables
Symbol Units Description
Output Display Indices:
MI n/a Mechanical Index
TIS
scan
n/a Soft Tissue Thermal Index (scanning mode)
TIS
non-scan
n/a Soft Tissue Thermal Index (non-scanning mode)
TIB n/a Bone Thermal Index
TIC n/a Cranial Thermal Index
Intensity, Power, and Pressure Parameters:
I
SPTA.3
mW/cm
2
Spatial Peak-Temporal Average Intensity derated to 0.3 dB/cm
/MHz
I
SPPA.3
W/cm
2
Spatial Peak-Pulse Average Intensity derated to 0.3 dB/cm/MHz
I
TA.3
mW/cm
2
Time average Intensity, derated to 0.3 dB/cm/MHz
PII
max
n/a Maximum free-field pulse intensity integral
W
0
mW Ultrasonic Power
W
.3
(z
1
) mW Derated ultrasonic power at axial distance z
1
P
r
MPa Peak rarefactional pressure
P
r.3
MPa Peak rarefactional pressure, derated to 0.3 dB/cm/MHz
Transmit Parameters:
f
c
MHz Center Frequency
PD s Pulse Duration
PRF kHz Pulse Repetition Frequency
Distance/Depth and Area Parameters:
d
eq
(z) cm
Equivalent beam diameter as a function of z, = [(4/ )(W
0
/I
TA
(z))]
1/2
z
sp
cm Axial distance to spatial peak
z
1
cm Axial distance to the location of max[min(W
.3
(z), I
TA.3
(z) x 1 cm
2
)] where z
z
bp
z
bp
cm Break point depth = 1.69(A
aprt
)
1/2
ROC cm Radius of curvature
FL cm Focal Length
A
aprt
cm
2
Area of Active Aperture
Table 6–142. Index Tables Key