5-24 Image Optimization
5.7.3 PW/CW Doppler Mode Optimization
Gain
Description
This function is intended to adjust the gain of spectrum map. The real-time
gain value is displayed in the image parameter area in the upper left corner
of the screen.
Operation Rotate the <iTouch> knob clockwise to increase the gain, and
anticlockwise to decrease.
Or adjust it in the image parameter area.
The adjusting range is 0-100.
Effects Increasing the gain will brighten the image and you can see more received
signals. However, noise may also be increased.
Frequency
Description
Refers to the operating frequency in PW mode of the probe, the real-time
value of which is displayed in the image parameter area in the upper left
corner of the screen.
Operation Select the frequency value through the [Frequency] item in the soft menu
or menu.
Or adjust it in the image parameter area.
Values of frequency vary depending upon the probe types.
Select the frequency according to the detection depth and current tissue
characteristics.
Effects The higher the frequency, the better the resolution and sensitivity, and the
worse the force of penetration.
Scale
Description
This function is used to adjust the speed range of color flow, which is
adjusted through PRF in the system. The real-time PRF value will be
displayed in the image parameter area in the upper left corner of the
screen.
Operation Adjust the speed range through the [Scale] item in the menu or the soft
menu.
The adjusting range varies by frequency, probe and depth; adjust
according to the actual situation.
Effects To provide a much clearer color flow image.
Use low PRF to observe low-velocity flows, and use high PRF to observe
high-velocity flows.
Impacts Aliasing may occur if low velocity scale is used and high velocities are
encountered.
Low velocities may not be identified when a high velocity scale is used.