LCD screens have become a common piece of hardware in many households, replacing old cathode-ray tubes in TVs as well as computers. As the screens grow bigger and bigger, the flatness of their component layers becomes more important. An uneven middle layer in an LCD screen often results in “clouding”, also known as the mura effect. A patent application from a Chinese company aims to resolve clouding by using graphene.
An LCD screen consists of several layers, most importantly the active LCD matrix, and a colour filter which is used to set the colour of each individual pixel. The two core layers of a screen are typically joined by a layer of glue and an electrically conductive layer which brings power to the pixels. Clouding results from an uneven glue sealant layer. Furthermore, the conductivity of the sealant-conductor combination is often poor. Patent application number 20130077030, filed by Shenzhen China Star Optoelectronics Technology Co. Ltd (CSOT), offers to use a special conductive glue, filled with graphene or carbon nanotube particles to make it conductive. The conductive glue would be less than 7 micrometers thick, helping to get rid of clouding.
CSOT is known for making very large LCD panels. Last year, the company made the world’s largest (110 inch) LCD screen. This is the first graphene patent by the company.