Touch Screen Display Latency Explained

When discussing the term latency in regards to touch display applications, there are a couple of things to keep in mind when it comes to overall performance. In this blog we will shed some light on the various terms regarding latency and what to look for when testing how a touch display performs under your finger or stylus.

Latency

Latency is simply the time it takes for the user to see feedback from the touch display device as a consequence of a signal gesture via stylus or finger. Another term often used is Touch Responsiveness, which can also be described as the time it takes a user to press the touch display and the amount of time it takes for the gesture to be visible on the display.

Latency can also be categorized into three different types. Tap Latency, Initial Motion Latency, and Move Latency.  Tap latency is the time from a “touch up“ or “touch down” event on the display. Whenever the user removes their finger / stylus or presses down on the display surface until the time something happens on the display as a consequence of the triggered event. Initial Motion Latency can be described as the moment from the first “motion” event until the time something happens on the display as a consequence of the triggered event. Lastly, Move Latency is the same as initial motion latency but measured later during a swiping gesture.

The Good, The Bad, The Ugly

As iPads, smartphones and other touch devices become everyday used items, users are becoming more familiar with the performance aspects of touch applications.

With great performing Touch Response Latency, the user will experience little to no lag as they move their finger across the screen, while people experiencing high latency issues will experience a momentary lag behind their various gestures. This can be extremely frustrating, especially if you are in the middle of an important presentation. One thing to look for if you are experiencing high levels of latency is the overall calibration of the display. Often times it can be as simple as the calibration being off, causing the lag. In that case, a simple recalibration through the touch software’s preference will suffice.

Another cause for high levels of latency can be due to the fact that the device that is operating the touch display isn’t powerful enough to drive it. This issue is commonly referred to as System Latency.

While most people assume that touch hardware is the main culprit, it can be a variety things, usually stemming from software or system limitations. A newer computer or powerful video card with high levels of computing power can solve this issue.

Why Is Low Latency Important?

Low latency touch responsiveness should be overall performance standard when it comes to end users no matter the application. From hands on business conferences to schematic design reviews for architects, the less system latency there is, the more responsive and faster the display will operate.

Contact Volanti Displays

For more information or if you would like to set up some time to discuss your display ideas feel free to contact Volanti Displays.

Office: 408.579.1620
Hours: 8AM – 5PM PST