What is a Touchscreen? – IoT Design Support

Introduction

A touchscreen is a computer display screen that is also an input device. The screen is sensitive to pressure; a user interacts with the computer by touching pictures or words displayed on the screen.

The two types of touchscreen technology used within our products are:

Resistive

The most common & most cost effective Touchscreen solution found within industrial environments.  A resistive touchscreen panel is coated with a thin, metallic, electrically conductive and resistive layer, effectively forming a sandwich, with air in between. When the screen is touched, at the point of contact these two layers connect, the location of this is then processed by the touchscreen controller & the required action is performed. Resistive touchscreen panels are suitable for users who must wear gloves within their working environment, as they do not rely on an electrical impulse to register the touch event, which must be present when using projected capacitive touchscreens. They can also be operated with bare hands or with a standard touchscreen stylus.  Proper care & usage must be observed at all times as the resistive layer can be damaged by sharp objects. Resistive touch screen panels are not affected by outside elements such as dust or water.

Projected Capacitive

A projected capacitive touch screen panel is coated with a material that stores electrical charges. When the panel is touched, a small amount of charge is drawn to the point of contact. Circuits located at each corner of the panel measure the charge and send the information to the controller for processing.  Projected capacitive touch screen panels must be touched with a bare finger or a special conductive Touchscreen stylus, unlike a resistive panel.  Projected capacitive touch screens are also not affected by outside elements.

Selection

For advice on the ideal route for your new project, speak to DSL’s technical engineers for no obligation advice – we’re happy to help!