Acoustic Power Control; Acoustic Output Description; Damping Output Parameter - Youkey Q7 Instructions For Use Manual

9.6 Acoustic power control

Sound output depends on the system operator, the operator should obtain qualified under the premise
of effective diagnostic image to reduce the acoustic output. There are three types of operation control
and sound output control: direct control and indirect control and receiver control.
⚫ Direct control
The system of direct control of acoustic output through the soft menu area [] sound power project
adjusting acoustic output size. But in any mode of the acoustic output maximum value can not
exceed the acoustic output limit (MI limit of 2 TI, the limit value is 6, ISPTA.3 limit of 720
mW/cm2).
⚫ Indirect control
Indirect control of acoustic output is mainly caused by the control of image related parameters.
These include control operation mode, probe and frequency, focus, depth image and pulse repetition
frequency (PRF).
The operating mode determines the ultrasonic beam is scanning and non scanning mode, the thermal
effect with M, Doppler, Color are closely related.
The attenuation of the tissue is directly related to the change of the probe and its frequency. The
image depth is related to the effective aperture of the probe.
⚫
Receiver control
The receiver (such as gain control, dynamic range, image processing etc.) does not affect the sound
output. Therefore, in image optimization, priority should be adjusted to optimize the image receiver
control class, followed by direct control and indirect control.

9.7 Acoustic output description

9.7.1 Damping output parameter

In order to determine the relevant parameters of the acoustic output, compared to using a method
of ultrasonic system for different frequencies and different depth of focus. This method (also
called attenuation method) by measuring the acoustic output. In the water that ultrasonic wave
propagation in tissues. Usually 0.3 dB/cm/ MHz average sound intensity attenuation, namely
ultrasonic probe send each transmission of a 0.3 dB/MHz cm ultrasonic intensity attenuation, the
calculation formula is as follows：
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