The display market needs more different solutions for differentiation. Touchscreen displays come with different shapes on top layers: sensor-on-lens (SoL) or simple glass solution (OGS), glass-film (GF), glass-film-film (GFF), and some more.

So-called "on-cell" integrated sensors are mounted on the top of the color filter glass: these include 2-layer touch sensors with jumpers, or single-layer on-cell sensors, known as single-layer-on-cell (SLOC). A fully integrated "in-cell" sensor is designed to take advantage of the existing layers of the display cells and typically use the common electrode layers as a touch sensor matrix. The metal layers are used as intermediate bonds. In addition to those just mentioned, there are also hybrid "In-Cell / On-Cell" designs.

The advantages and disadvantages of the individual display sensors are debatable. Integrated sensors enable thinner and, above all, lighter displays, better optics, as well as some savings in terms of delivery costs. However, "in-cell" designs require complex coordination between the touch and display functions, which must be better distributed among the shared electrodes and in order to manage the so-called display noise, as well as to optimize touch performance.

In October last year, the American company Synaptics Inc. issued a press release announcing the acquisition of Renesas SP Drivers Inc (RSP). The RSP is a supplier of small and medium-sized display driver ICs (DDICs) used for smartphones and tablets. Through the acquisition of the RSP products, as well as the technology behind them, Synaptics intends to improve its own solutions for the mobile display market in the future, as well as further expand its presence in the touch and DDIC product segment through cost-effective touch and display drivers.

If you would like to learn more about the functionality and structure of the sensor of a projected capacitive touchscreen, you can find more information on our website.