From: Embedded.com -- How to Calibrate Touch Screens (talks about their own software which helps people create touch screen products) -- From 2002
http://www.embedded.com/showArticle.jhtml?articleID=9900629<snip>"...The calibration method requires that three targets or test points-no more, no less-
be displayed and touched in sequence to determine the screen's individual calibration factors. These calibration factors are then used to translate screen coordinates into true display coordinates. "
<snip>
From Neomtron: Hardwar support: Industrial Control Computer(ICC) Family General Issues...
http://www.nematron.com/Hardware_Support/support_icc_general.shtml#faq8Why isn’t my touchscreen working properly?
The problem could be:
Calibration: The touchscreen may only need to be calibrated due to age or changes in user viewing angle.
To calibrate in Dos, change to the touch directory and enter Elocalib. Select the appropriate display resolution and follow the instructions on the screen. Answer Yes or OK to all the questions regarding saving the calibration parameters in the Autoexec file. If this is not done, the new calibration points will be lost when the unit is restarted.
To calibrate in any Windows environment, open the Control Panel, click on the Elo Touch Icon, and click on Calibrate.
Press the targets as instructed and answer Yes to the question regarding accuracy once you are satisfied with the operation. This will return you to the Elo configuration screen. Click on the Apply or OK box to save the calibration. NOTE: On 640 x 480 resolution screens, the task bar at the bottom of the display may hide the buttons. Hide the task bar or move the Touch window up to access the buttons. Click OK or the close button to return to normal operation.
<snip>{emphasis mine}
Article on Early Voting problems in Computer World:
http://msn.pcworld.com/news/article/0,aid,118351,00.asp<snip>
"Of the 666 incidents reported in Florida, 33 have been linked to alleged voting machine malfunctions in Broward, Duval, Lee, Marion, Miami-Dade, Orange, Palm Beach, Sarasota and Volusia counties.
In Broward County, for example, some voters complained of electronic touch-screen systems that presented incomplete ballots.
Alia Faraj, spokeswoman for Florida Deputy Secretary of State Dave Mann, said contrary to news reports, there have been no problems during early voting related to any of the touch-screen electronic voting systems in Florida. The only problems that did occur, she said, involved laptop computers that were used to check voter registration rolls in some of the counties.
Those problems were fixed immediately by a simple reboot of the computers, said Faraj. "The touch-screen systems have been operating as planned," she said.
Will Doherty, executive director of the San Francisco-based Verified Voting Foundation, said despite Florida's assertion that the malfunctions of the laptops handling voter registrations were minor, his organization is aware of dozens of voters who were turned away from the polls "because of that minor system crash."
Doherty also said there have been multiple reports related to touch-screen calibration problems. Some voters have reported that when they touched the screen next to their candidate's name the screen highlighted the opposing candidate, according to Doherty."
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From a Linux Software Site
http://www.touch-base.com/main.asp?item=21To calibrate, double click the calibration icon on the desktop or run the calibration program and touch the calibration crosses, or arrows, as they appear.