If the coverglass is fully glued to the touch sensor and the TFT, and if any damage occurs the company will have to bear the expense of replacing the complete stack. However, with the airgap added in between, in case of any damage, only the coverglass has to be replaced without the need of replacing the entire stack. So replacement becomes cost effective, quick, and easy.
However, when an air gap is introduced between the touch sensor and the cover lens, it becomes more difficult for the touch sensor to detect a finger touch, since the low dielectric-constant of air reduces the signal strength from a finger touch.
One way to solve this problem is to boost the touch system’s sensitivity threshold.
However, this may also attract more noise from the environment, which makes it more difficult for the touch sensor to differentiate a touch from the noise.
For this reason, Avnet Embedded has developed special patterns and parameters for our DITO sensors, so that our solution works now with an air gap on top of the sensor.
The maximum air gap we allow is 0.5mm and ta maximum glass thickness is 7mm. We can do a ruggedized solution that can pass all EMC tests and works also well with gloves and water.
To know more about our AIR GAP stack and other solutions, please get in touch with our team.