Polymer nanocomposites for illumination: towards warm white light

The aim of this PhD project, also called “warm white light project”, is to propose an alternative solid state lighting device that works using the same principles of color-conversion WLEDs. The idea is to create a polymer based nanocomposite that could work as a transparent glass in off-mode and as a “lamp” in on-mode. The new concept is to spatially decouple the light source and the converters in order to avoid all the thermal problems that affect the current LEDs (in which the color is “generated” within the chip and the epoxy case). To do so, a blue LED, made of Indium gallium nitride (InGaN), is coupled to a bulk polymer nanocomposite sheet where the actual conversion of light takes place. For emitting white light it is necessary that the nanocomposite would not only convert partially the blue light into warmer colors (like yellow and red) but also diffuse the blue light outside in order to have a color mixing.