High Refractive Index Carbonized Polymer Dots Acting as Light Scattering Units in Nanocomposites for Full-Screen Light Guide Plate

The full-screen mobile phone can be fabricated by integrating the camera beneath the screen, which needs the nanocomposite light guide plate (nano-LGP) with exceptional transparency and light-guiding properties simultaneously. Choosing an appropriate nanoparticle with a high refractive index and exceptional compatibility within the polymer matrix is crucial for producing the nano-LGP. In this study, the high refractive index carbonized polymer dots (HRI-CPDs) are synthesized through the solvothermal treatment, achieving a refractive index value of 1.7220 at 450 nm. Subsequently, the modified HRI-CPDs (mHRI-CPDs)/polymethyl methacrylate (PMMA) nanocomposites are fabricated by copolymerizing the mHRI-CPDs with methyl methacrylate . Due to the high visible light transmittance and Rayleigh scattering characteristics when light passes through the nanocomposites, this kind of nanocomposites is suitable for serving as nano-LGPs. The potential of carbonized polymer dots as light-scattering unit is originally explored to improve surface illuminance and uniformity of nano-LGPs. The best-performing 4.3-inch LGP with 1.0 wt.% doping content shows 15.8 times higher surface illuminance and 2.1 times higher uniformity than pure PMMA. This new type of LGP based on mHRI-CPDs/PMMA nanocomposite holds tremendous promise in conjunction with advanced liquid crystal display technology.