Touchscreens

Touchscreens

Touch-sensitive displays offer a wide range of possibilities for a simple and convenient operation of devices. There is, however, no touch technology that can be used universally for every application. All technology has advantages and disadvantages, each of which should be carefully evaluated. In order to achieve an optimal solution, it is important to know and understand the essential technologies.

  • Resistive touchscreens enable precise positioning with stylus pen and gloves
  • Capacitive keyboards are extremely resistant to environmental influences and demonstrate a high degree of temperature insensitivity
  • Inductive touchscreens are mainly used for graphics system
Photo of a capacitive keyboard

Capacitive touch

Capacitive keyboards are characterised by a very robust and visually appealing design. As opposed to a resistive touch, a capacitive touch also works without pressure. All the user has to do is touch it to interact. The surface can be composed of glass or plastic. Individual buttons, as well as sliders and rotary knobs are used for actuation. Keyboards with glass surfaces can be manufactured in many different variants.

The first thing to consider is the selection of the glass to be used:

  • Clear
  • Optically anti-reflective
  • Chemically anti-reflective
  • Tempered glass
  • Thickness of the glass

The next question to address is that of machining:

  • Cut only
  • Ground or polished edges
  • Additional milled edges for openings or surface grinding for the fingertip guide are possible.

Capacitive touch: Your advantages

  • Robust (protection against vandalism)
  • Very long working life
  • Optically appealing
  • Lots of display possibilities
  • Surface made of glass or plastic
  • Easy to clean
  • Good readability, minimal reflections due to bonding

Resistive touch 

Resistive touchscreens function by means of pressure commands. No matter whether pressing with the whole finger, the fingernail or a pen. By pressing together the two layers under  DC voltage, the voltage at the edges of the upper polyester membrane can be measured and the position of the pressure point attained. Overview of all features:

  • Robust
  • Wear due to moving films and surface
  • Variations through display
  • Glove operation unrestricted
  • Universal stylus pens
  • Sealing depending on installation
  • Readability is poorer than that of capacitive touch, reflections due to membrane distance are increased
Graphic of how a resistive touchscreen works

Contact partner

Portrait of Dirk Deiters

Dirk Deiters
Product Management Input Sytems
Phone+49 1738724929
dirk.deiters@ksg-pcb.com

Portrait of Robert Ratheiser

Robert Ratheiser
Product Management Input Sytems
Phone+43 2985 2141-520
robert.ratheiser@ksg-pcb.com