Casio QT-7300 Service Manual page 32

4-16-2-1. Calibration
1) For Windows 98 SE and Windows 2000
(1) Insert Floppy disk into Floppy Disk Drive ("A:").
(2) Open "Explorer" <Click "Start", select" Programs" then select "Windows Explorer" >.
(3) Click Floppy Disk Drive ("A:") in "All Folders"
(4) Double Click "CALWIN(CALWIN.EXE)" then execute.
(5) Calibration Program. (Nine "+" marks will be shown on the display)
(6) Hit "+" marks (touch on the touch panel).
Color of "+" mark will be turned Black or Red by each touch, if touch is recognized.
(7) After touch all nine "+" marks, hit "Enter" key.
(8) Hit "Enter" key after "+" marks disappeared to finish.
Note at calibration :
1) You will be prompted to touch nine calibration points on the screen. Before you touch, position
yourself in front of the screen in 90-degree vertical angle against the screen.
2) Use sharp soft object (i.e. pen shaped plastic object) instead of your finger for accurate positioning.
3) Please do not use any hard sharp objects (i.e. knife, metal ballpoint pen), it may cause damage
on the touch screen panel.
4) Calibration data will be stored in the EEPROM on the touch screen controller board. You will not
need to calibrate at each system start by power on as long as data is stored in the EEPROM.
Why Calibration is Necessary?
The necessity for calibration is unique to the touch screen. Unlike mouse or keyboard applications where the
cursor is part of the image, a touch screen is a physical overlay with an independent coordinate system. Only
by knowing the position of the image can the PC software convert touch screen coordinates into image
coordinates.
Besides the differences among touch screens and controllers, calibration also compensates for the variation in
video image among displays. The image is affected by horizontal and vertical adjustments on the monitor and
by the physical mounting of the touch screen.
Additional calibration complications include image blooming, where bright-colored images expand, and the "pin
cushion" 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.
Perfect calibration cannot be achieved in all circumstances. For example, the user can encounter parallax
problems with a change in position, or because the present user is not the same stature as the person who
calibrated the screen.
When Re-calibration is Necessary?
Once calibrated, the touch screen will be ready to run automatically each time the system is restarted. Re-
calibration should only be necessary after moving or resizing the video image, or after changing either the touch
screen, controller, or monitor.
Refer calibration procedure based on your O/S system and re-calibrate if necessary.
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