How touch screen technology works

Multi-Touch Screen Technology

Most touch screens can only respond to one touch at a time. Multi-touch technology allows, as the name suggests for multiple touch points at the same time on the screen. This can create exciting and new applications, particularly in the areas of flicking, touch, hold, panning, zooming and rotating.

TouchScreen Solutions can supply touch screens that work with Windows 7 gestures “Plug and Play”. For a demonstration on how this multi-touch technology works please view the video.

Please contact us to discuss your requirements further if this is of interest to you.

Infrared Touch Screen Technology

Infrared technology uses a small frame around the display with LED’s and photo receptors hidden behind an infrared transparent bezel. The controller pulses the LED’s to create a grid of IR light beams. A touch obstructs the beams which identifies the X and Y coordinates.

infrared-touch-screen-technology

TouchScreen Solutions supplies all popular touch screen technologies. For most applications, if the budget allows we recommend infrared technology. Whilst this technology is more expensive to produce than others, it is generally a more robust and preferred solution.

Benefits of infrared technology:

  • Can be scaled to any size without losing resolution
  • Calibration stability – no touch point drift
  • High clarity and light transmission
  • High chemical, scratch, breakage, and liquid resistance
  • High sealability from dust and liquids
  • Touch can be activated by anything including finger, gloved hand, or stylus
  • High durability since a touch is only interrupting light beams

Popular brands that often use infrared touch screen technology:

  • Nexio (NXO)
  • IBM
  • ELO
  • Samsung
  • Philips
  • NEC

Please contact us to discuss if infra-red technology is the best solution for your requirements.

SAW Touch Screen Technology

Surface Acoustic Wave (SAW) touch screen technology is based on sending acoustic waves across a clear glass panel with a series of transducers and reflectors. When a finger touches the screen, the waves are absorbed, causing a touch event to be detected at that point.

Like infrared technology, the panel is all glass, so there are no layers that can be worn, or damaged over time. This makes SAW touch screen technology highly durable and suitable for applications where high clarity is desired.

SAW-touch-screen-technology

SAW touch screen technology is recommended for public information kiosks and other high traffic indoor environments.

In Australia SAW technology is usually one of the more expensive technologies. Since there are few applications where it is superior to infrared, infrared is more often the recommended solution where high durability and screen clarity is required.

Limitations of SAW Touch Screen Technology

  • Must be touched by finger, gloved hand, or soft-tip stylus. Something hard like a pen, credit card or finger nail won’t work.
  • Can be affected by large amounts of dirt, dust, and / or water in the environment.
  • Relatively expensive in comparison to other technologies.

Popular Brands that often use SAW Touch Screen Technology:

  • ELO

Please contact us to discuss your if SAW touch screen technology is the right technology for your application.

Infrared Touch Screen Technology

Resistive touch screen technology consists of a glass or acrylic panel that is coated with electrically conductive and resistive layers. The thin layers are separated by invisible separator dots. When operating, an electrical current moves through the screen. When pressure is applied to the screen the layers are pressed together, causing a change in the electrical current and a touch is registered.

resistive-touch-screen-technology

Although clarity is less than with other touch screen types, resistive screens can be highly accurate and have the advantage of being pressure sensitive so it responds to any input device, including finger, gloved hand, or pen stylus.

Resistive touch screen technology is the most cost effective technology on the market today. It is recommended when budgets do not allow more robust solutions.

Limitations of resistive touch screen technology:

  • Can be relatively easily damaged by scratching
  • Can be relatively easily damaged by poking
  • Can be relatively easily damaged by impact
  • Not recommended for public access applications
  • Requires periodic recalibration
  • Can wear through regular use over time

Popular Brands that often use resistive touch screen technology:

  • LG
  • TSS

Please contact us to discuss if resistive touch screen technology is the right solutions for your requirements.

Capacitive Touch Screen Technology

Capacitive touch screen technology is a popular and durable technology that is used in a wide range of applications. It has a higher clarity than resistive technology, but it only responds to finger contact and will not work with a gloved hand or pen stylus.

A capacitive touch screen consists of a glass panel with a capacitive (charge storing) material coating its surface. Circuits located at corners of the screen measure the capacitance of a person touching the overlay.

Capacitive-touch-screen-technology

Capacitive touch screen technology is often recommended to customers who would like the confidence of a brand name LCD such as NEC, which the capacitive touch screen would then be retrofitted to.

Limitations of capacitive touch screen technology:

  • Can not be used with a gloved hand
  • Can not be used with stylus
  • Requires periodic recalibration
  • Often retrofitted to standard non-touch LCD monitors which may not be as stable when touched
  • Not usually fitted to monitors when applications require dust, water, scratch or impact resistance

Popular Brands that often use capacitive touch screen technology:

  • 3M Microtouch

Please contact us to discuss if capacitive touch screen technology is the right technology for your application.