Image Optimization  5-23 
Arrow Size 
Description  Used for adjusting the arrow size. 
Operation  Rotate the knob under [Arrow Size] to adjust the parameter. 
Impacts 
The end point of the arrow does not change with the value becoming larger, but the 
arrow length becomes longer. 
The end point of the arrow does not change with the value becoming smaller, but the 
arrow length becomes shorter. 
 
Trig Type 
Description  Set trigger type. 
Operation  Under V Flow mode, turn on ECG and select “Manual” or “R” or “R100/200/300/400” 
trigger mode. Image will be captured in 100/200/300/400ms after R wave and ECG 
wave will be marked by red at that time. 
  Tap [Trig Type] to select the levels: manual, R, R100, R200, R300 and R400. 
 
ROI Size 
Description  Adjust the size of ROI. 
Operation  Tap  [ROI Size] on the touch screen to adjust. 
 
Acquire Time 
Description  Set the acquisition time. 
Operation  Tap  [Acquire Time] on the touch screen to adjust the acquisition time. 
 
Sensitivity 
Description  This function is an indication of the ability to detect flow, which is used to adjust the 
accuracy of color flow. 
Operation  Rotate the knob under the [Packet Size] item on the touch screen to adjust the value. 
0 represents no packet size control and the bigger the value is, the higher the 
sensitivity becomes. 
The higher the sensitivity is, the more sensitive indication for low-velocity flow 
becomes. 
  It affects the frame. 
 
5.7  PW/CW Mode Optimization 
PW (Pulsed Wave Doppler) mode or CW (Continuous Wave Doppler) mode is used to provide blood 
flow velocity and direction utilizing a real-time spectral display. The horizontal axis represents time, 
while the vertical axis represents Doppler frequency shift. 
PW mode provides a function to examine flow at one specific site for its velocity, direction and features; 
while CW mode proves to be much more sensitive to high velocity flow display. Thus, a combination of 
both modes will contribute to a much more accurate analysis.