Due to its stability, processability, and electrical and optical properties, PPV has been considered for a wide variety of applications. In 1989 the first polymer-based light emitting diode (LED) was discovered using PPV as the emissive layer. Polymers are speculated to have advantages over molecular materials in LEDs, such as ease of processing, reduced tendency for crystallization, and greater thermal and mechanical stability. Ever since the first breakthrough in 1989, a large number of PPV derivatives have been synthesized and used for LED applications. Although solid-state lasing has yet to be demonstrated in an organic LED, polyvinylene (MEH-PPV) has been proven to be a promising laser dye due to its high fluorescence efficiency in solution.