Inherent interference‐filter polymer light‐emitting diodes

A global or “systems” approach to the design of polymer‐based light‐emitting devices is shown to be important for an understanding of the details of light emission from these devices. A self‐interference‐filter type of light‐emitting device with a very narrow spectral output–a prerequires for many applications but difficult to realize because of the typically broad electroluminescence emission spectrum–is described, in which color selection is achieved by the appropriate combination of layer thickness and values of refractive index of the components of the device structure.