At SID Display Week, there are over 40 touch screen related exhibitors. One specific implementation, on-cell touch, integrates the ITO layer (or layers) on the top surface of the LCD color filter glass, or for OLED on the encapsulation glass. On-cell touch enables thinner, lighter weight devices compared to add-on type projected capacitive touch, due to the lack of dedicated touch sensor substrate (or substrates).
According to our Touch Panel Market Analysis report, on-cell touch was used in LCDs in 2010, but due to the challenges of the manufacturing process, disappeared in 2011. While Samsung uses on-cell touch for their super AMOLEDs, the AMOLED’s encapsulation glass doesn’t have the color filter on it, making on-cell relatively easy to integrate.
At the show, E Ink’s Hydis Technology demonstrated their new LCD with on-cell touch, which uses single-layer ITO, meaning that it doesn’t need insulator bridges, and which also saves cost and avoids damage to the color filter (due to the use of high processing temperatures). The display is capable of 10 point multi-touch.
Hydis indicated that it can supply on-cell touch LCD up to 22”. The company is perhaps best known as the inventor and developer of fringe field switching (FFS) technology, which is featured in many smartphones and most tablets currently in the market. Hydis asserted that the combination of FFS and on-cell touch can offer better performance at lower cost. Hydis will begin offering the on-cell FSS LCD technology to the smartphone and tablet markets beginning this month.