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Chapter 3 - Using MonitorMouse for Windows NT
Running the Touchscreen Control Panel
1.
Touch the Start button, then touch Settings, then touch Control Panel.
2.
Double-touch Elo Touchscreen to run the Touchscreen Control Panel.
Calibration
Select Calibrate to initiate the calibration sequence. Follow the on-screen
instructions. You will be given the opportunity to confirm the calibration points.
The need for calibration is unique to the touchscreen. Unlike mouse or keyboard
applications where the cursor is part of the image, a touchscreen is a physical
overlay with an independent coordinate system. Only by knowing the position of
the image can the driver software convert touchscreen coordinates into image
coordinates.
Besides the differences in touchscreens and controllers, calibration also
compensates for variations in the video image among displays. Calibration is also
affected by horizontal and vertical adjustments on the monitor and by the physical
mounting of the touchscreen.
Additional calibration complications include image blooming, where brightly-
colored images expand, and the "pincushion" effect, which causes the corners of
the display to be stretched. Poor display linearity can cause similarly sized boxes
to be larger at the edges of the screen than they are in the middle, or vice-versa.
The displayed image can also be tilted. Even changing video modes can affect the
screen size.
The three-point calibration sequence used by the Touchscreen Control Panel
automatically corrects inverted touchscreen installations and backwards cable
connections.