User's Manual

Acclarix AX3 Series Diagnostic Ultrasound System User Manual Ultrasound Intensity and Safety
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Table 1 The intensity and pressure measurement uncertainties table
Total uncertainties
Hydrophone
Sensitivity
Digitizer
Intensity
Pressure
Intensity
Pressure
Intensity
Pressure
Uncertainty
±23.68%
±11.84%
±14%
±7%
±0.95%
±0.475%
Notes
The RMS combination of all
sources of measurement
uncertainty, based on all
sources being independent.
Uncertainties based on
the hydrophone
calibration certificate.
Uncertainties based on
oscilloscope calibration
certificate.
Table 2 The intensity and pressure measurement uncertainties table
Temperature
Spatial Ave.
Distortion
Intensity
Pressure
Intensity
Pressure
Intensity
Pressure
Uncertainty
±2.39%
±1.195%
±18.5%
±9.8%
±4%
±2%
Notes
Uncertainties based on
temperature variation of the
water bath and difference in the
mean temperature between the
hydrophone calibration lab and
our facility.
Uncertainties based on
part 7 of B.7 and
discussions with industry
consultants.
Non-linear distortion
estimates are based on
part 7 of B.7 and
discussions with industry
consultants.
Table 3 The power, center frequency and MI measurement uncertainties table
Power
Center frequency
MI
Uncertainty
±23.68%
±0.2%
±11.84%
Notes
Uncertainties based on
the intensity uncertainties.
Uncertainties based on
the oscilloscope.
Uncertainties based on the
pressure and center frequency.
B.4.4 Acoustic Power Default Settings
The ultrasound system allows direct control of acoustic power by the Power paddle key on the touch
screen. The range can be adjusted is 10% to 100%. The higher the acoustic power number, the
greater the acoustic output.
The factory default settings of acoustic power is 100%. The default settings can be reconfigured by
the operator through the Acoustic Power item on ->Preset->Image Preset page. The
ultrasound system switch to default settings upon power up, new patient, new exam or new
transducer.
B.5 Operator Control Features
The possibility of producing mechanical/thermal biological effects can be influenced by three kinds of
controls: Direct Controls, Indirect Controls, and Receiver Controls. The qualified operator may use the
system controls to minimize the ultrasound output while acquiring necessary clinical information.
 Direct Controls
The acoustic output of the system can be controlled directly through the level of voltage transmitted.
In this case, the maximum acoustic output never exceeds the limits in any mode of operation.