Choose the right touch technology for your display

   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 in 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. This is an especially important aspect for products used is areas, such as medical applications where there may be in some spillage, leaks, spray, unsanitary aspects—and the ability to both seal to some extent, and wipe the GUI clean, is an asset.

   [Note: we have run many articles on touch screens and associated technologies; you can see a list of all of them with links here.]

   Deciding on the right touch technology can be challenging for even the seasoned technology guru. With over 1200 touch-related patents in existence, it is easy to become confused about which touch technology to choose to integrate into a new product.

   When choosing a touch screen, it’s important to first carefully evaluate the needs of your product and the environment of the display. Once your key requirements have been identified, it’s easier to weigh the advantages and disadvantages of each technology to find the touch screen that’s right for your application.

   This article, from sibling publication Medical Electronics Design (MED) beings with basics: What is touch and how is a touch recognized? What is multi-touch? For the following touch technologies, it looks at reasons to choose a given approach, additional benefits and capabilities, how it works, and factors affecting the display:

•Analog resistive

•Surface capacitive touch technology

•IR sensing

•Surface acoustic wave

•Optical touch

•Multi-touch analog resistive

•Dispersive signal

•In-cell/on-cell touch

•Acoustic pulse recognition

Click on "Choose the right touch technology for your display" to read the article.

About the author

Gary Barrett is the Founder and CTO of Touch International. He holds five key patents related to analog resistive and capacitive touch sensing technology and has consulted in the development of touch panels with companies around the world.

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