Liquid crystal coating enhances OLED display contrast performance
Light Polymers plan to enable reverse dispersion coatings directly on the OLED panel glass. Lyotropic liquid crystals are a novel class of materials that have the potential to revolutionize many aspects of light management in displays.
One of the issues with the poor contrast of OLED displays in bright ambient environments are the reflective transistors that drive each pixel. The traditional solution is to add a linear polarizer and quarter-wave plate (to convert to circular polarization) on top of the OLED panel. This helps, but produces a color shift for off-angle viewing.
To improve this, a reverse dispersion quarter-wave plate film must be used and gives a more uniform black state and lower color shift. The Lyotropic liquid crystals from Light Polymers offer similar levels of performance but at lower cost and has the ability to be coated directly onto the OLED panel, something competitive technologies cannot do.
The CR006 lyotropic liquid crystal material will enable OLED displays to have deeper black color in the off state and improve the contrast ratio. Additionally, CR006 serves as an antireflective layer that improves viewability in bright sunlight conditions. Initially CR006 is available for coating COP substrates. By the end of 2015, Light Polymers’ reverse dispersion materials will be coatable on any substrate including TAC, Polycarbonate, Acrylic and glass.
"CR006 is a water-based solution that offers great flexibility and simpler manufacturing than competitive approaches," noted Sergey Fedotov, Technical Product Manager. "This OLED material is the first in a family of solutions we plan to offer across the range of light management points in displays."
"OLED displays continue to advance in market share especially in mobile, HDTV and now in wearable products," concluded Marc McConnaughey, President/CEO of Light Polymers, Inc. "Recent introductions of wearables by major brands generally use OLED and in some cases flexible OLED’s, so we see great potential for our solutions in this fast moving segment."
Light Polymers is currently qualifying coating equipment manufacturers for implementing lyotropic liquid crystal materials in production. The coating methods are slot die and microgravure for coatings on substrates and slit coating for coatings on glass. Unlike other liquid crystal materials, Light Polymers’ CR006 does not need a secondary alignment process such as rubbing or photoalignment which brings a reduction in the number of production process steps, giving a cost advantage to this technology.