Liquid Crystal Optical Coatings for Flexible Displays

In many flexible display designs, optical coatings enhance the viewing experience or are an essential part of the display optics. This chapter reviews the liquid crystal network (LCN) technology and the various optical film technologies that can potentially be integrated in flexible display designs. Often, they are not explicitly developed for flexible display applications, but can be adapted to and employed in flexible applications. The chapter discusses the basic principles of LCN technology and their use for thin-film polarizers, retarders, and color filters. Often organic light-emitting diode (OLED) displays have a circular polarizer at the viewing side to improve them on daylight contrast. By constructing the circular polarizer from an reactive mesogens (RM)-based dichroic polarizer in combination with an RM-based quarter wave film, the circular polarizer can be kept very thin without sacrificing the bendability of the OLED pane.