Researchers in Canada and the UK has developed a flat panel display (FPD) that is based on photonic crystals that can reflect colors across the entire visible spectrum controlled by electricity. Since it is a reflective display there is no additional power consumption from a backlight, unlike transmissive or transflective displays. Colors can be tuned from 425nm to 900nm in wavelengths with very small voltages less than 2V. A large portion of the cost of manufacturing LCDs is composed of the backlight and color filters. Because this single material can generate the entire visible spectrum of colors, there is no need for a color filter. No backlight and no color filter may mean a very simplified process in manufacturing and that can very low cost. The researchers have been able to test samples up to 1 cm2 but stated that there does not seem to be a size limit for this technology.
The material is a nanocomposite, similar to the structure of natural gemstone opal, with electroactive polymers embedded for electrical voltage responsiveness. The voltage cause a structural change in the nanocomposite that cause the electroactive polymer to expand, pushing the spheres in the material apart, and generating a different reflected color. The greater the separation the greater the wavelength. The color spectrum is not limited to visible light but can expand to UV and IR ranges according to the researchers. Amazing technology!
[tags]Electroactive Polymer, Flat Panel Display, Nanocomposite, Opal, Photonic Crystal, Reflective Display[/tags]