5-16 Image Optimization 
Scale 
Description  This function is used to adjust the speed range of the color flow, which is 
adjusted using the PRF in the system. The real-time PRF value is 
displayed in the image parameter area in the top-right corner of the 
screen. 
Operations  Adjust through the [Scale] item on the touch screen. 
The adjusting range varies according to the frequency, probe and depth. 
Adjust according to the actual situation. 
Effects  Provides a much clearer color flow image. 
Use a low PRF to observe low-velocity flows, and a high PRF to observe 
high-velocity flows. 
Impacts  Aliasing may occur if a low-velocity scale is used and high velocities are 
encountered. 
Low velocities may not be identified when a high-velocity scale is used. 
 
Baseline 
Description  Refers to the area where the velocity is zero in the scale. Adjust according 
to the actual situation so as to get an optimum flow display. 
Operations  Adjust through the [Baseline] item on the touch screen. 
A positive value means increase the signals above the baseline, and a 
negative value means increase the signals below the baseline. 
 
Invert 
Description  To set the display mode of the color flow. The color scale will be inverted 
when the function is turned on. 
Operations  Turn the function on or off using the [Invert] item on the touch screen. 
Select “Auto Invert” in “[Setup] (F10)Æ[System]Æ[Image]”, so the color 
bar can automatically invert when the color flow is steered to a certain 
angle to accommodate the operator’s desire to distinguish the flow 
direction. 
Auto invert function is available only for linear probes. 
 
Map 
Description  This function is a combination of several image parameters, which 
indicates the display effect of the color image. 
Operations  Rotate the knob under the [Map] item on the touch screen to select from 
among the maps. 
The system provides 21 different maps for selection. The V group provides 
11ordinary maps and the VV group provides 10 2D maps.