The pandemic situation has sensitized many people to reduce contacts with other people and devices. Technologies that work without direct contact are thus moving into the spotlight of interest. The challenge, then, is to find a touch system that can be operated without contact while providing the pixel-perfect resolution that a graphical terminal requires. Technologies such as time-of-flight, radar and ultrasound are ruled out for various reasons: the price or the accuracy in the two dimensions of the x/y plane, which requires a great deal of effort for integration and calibration.

A suitable system is the new generation of infrared touchscreens, which instead of interrupting the light grid of opposing transmitting and receiving diodes, evaluates reflections of any object introduced into the beam path. Together with intelligent evaluation that effectively suppresses false triggering, the advantages lie in the slim design on only one side of the display instead of all four, and the simple interface that can be connected directly to the host without a separate controller board.

The holographic terminal provides a virtual image that floats in mid-air. Since there is no haptic feedback, other methods of confirmation must be chosen. The non-contact nature reduces the risk of spreading viruses. It can be operated with any medium, including gloves, wet or dirty fingers, or a credit card. It supports single-point and gesture operation and can be connected to any computer with a video interface for the display and USB interface for the touch sensor. The technology is attractive and attracts attention even when there is no demand for touchless operation.

This white paper goes into detail about the components, working principle, practical examples, optimizations and tips to implement a "Holographic Touch".

Note: This white paper is in german.