Technical & Business Challenges of Display Integrated Touch | Cypress Semiconductor
Technical & Business Challenges of Display Integrated Touch
Author: Bart DeCanne
Projected capacitive touchscreens continue to see ever-higher market demand and have become, in just a few years’ time, the de-facto user interface for smartphones. Over the next couple of years, we will see this growth trend continue, with the technology further trickling down to lower-end feature phones. The industry has developed a well-established touch supply chain for this technology, including discrete sensor vendors patterning indium tin oxide (ITO) films or other transparent conductor material, touch controller IC suppliers, cover lens glass vendors, and display module vendors (LCD or OLED based). The various components of a touch module assembly are then integrated by a combination of contract manufacturers (CMs) for smartphone OEMs, sensor or cover lens vendor subcontractors, or display vendors. Touch module integration involves attaching the flex cable with the touch controller IC to the sensor, laminating the sensor assembly to the display module, and attaching the cover lens.
Display vendors, anxious to capture more value, have allocated significant R&D budgets over the past few years to integrate the touch function inside their LCD module. Display vendors already use ITO deposition for the interconnection of pixel elements across the display. Each pixel requires a thin-film transistor (TFT), with a source, gate, and drain that need to be driven with the appropriate signals to hold pixel data values. With display integrated touch, the discrete sensor vendor is effectively bypassed, simplifying the supply chain.
To read more, visit www.eetimes.com