Polyphenylene vinylene is capable of electroluminescence, leading to applications in polymer-based organic light emitting diodes. Subsequent exciton recombination results in electroluminescence (EL). A polarization of 8% was measured in the resulting electroluminescence. Powder or AC electroluminescence is found in a variety of backlight and night light applications. This porous material could emit visible light when a current was passed through it (electroluminescence). The Westinghouse group also reported on operational TFT electroluminescence (EL) in 1973, using CdSe. Additionally, mechanisms relating to triboluminescence, chemiluminescence, and electroluminescence have been suggested. Electroluminescence can be exploited in light sources. Electroluminescence is light emission stimulated by electric current. Electroluminescence is light resulting from an electric current being passed through a substance. "A Simple Organic Electroluminescence Diode"; D. F. Williams and M. Schadt.