Touch screens are “hot” as user interfaces and are increasingly popular. Whether they are small size, as in appliances or smartphones; medium size in tablets, gas-station pumps, or bank ATMs, or larger form factors used in full-size instruments, they are rapidly taking over for discrete mechanical switches and even QWERTY keyboards. They offer the flexibility of soft-keys and non-fixed functions, plus lower BOM and assembly cost, and they keep dirt and liquids out, as well.
However, they bring new challenges . Mechanical misalignment and scaling factors can lead to a mismatch between the values from a touch-panel system (in this article the touch-panel system implies a setup comprised of a touch screen and a touch screen controller) and the display (typically an LCD) on which the touch screen is mounted. This article discusses the mathematical techniques to calibrate the touch-panel system so you can match the graphics on the display to the output from the touch-screen controller.
This article is presented as four pdf files, beginning with:
Note : we have run many articles on touch screens and associated technologies; you can see a list of all of them with links here.
About the Author
Faisal Tariq is a Senior Applications Engineer with Maxim Integrated Products. He has been in the semiconductor industry for over 20 years and holds three patents that focus on flow control. Mr. Tariq has a BSEE from the University of North Dakota and an MSEE from Kansas State University.
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