A7.
If the measured result is not within 128±10ml, calibration is necessary. To begin, take 5 readings
of the phantom and average the results. This will be the “mean value” that is to be entered in this
formula:
128 (or standard value of phantom being used)
–
mean value = calibrating value
A8.
Select Calibration in the system reset screen for the device calibration.
A9.
Phantom Parameter:
Phantom Parameter:
•
Sound speed of background material
：
1540m/s±10m/s,23
℃
±3
℃
•
Attenuation of background material
：
0.7dB/(cm•MHz)±0.05dB/(cm•MHz),23
℃±
3℃
•
Protective plate
：
≤0.4mm
•
The internal target parameter of the Phantom
•
Weight: 1322g±0.1g
•
Density: 1021kg/m3±1kg/m3
•
Attenuation at 3MHz: 0.03dB/(cm·MHz)±0.02dB/(cm·MHz)
•
Sound speed at 23
℃
: 1547m/s±1m/s
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