In an embodiment of the invention, a microcavity OLED device that
minimizes or eliminates color change at different viewing angles is
fabricated. The OLED device can be, for example, an OLED display or an
OLED light source used for area illumination. This OLED device includes a
multi-layer mirror on a substrate, and each of the layers are comprised
of a non-absorbing material. The OLED device also includes a first
electrode on the multi-layered first mirror, and the first electrode is
substantially transparent. An emissive layer is on the first electrode. A
second electrode is on the emissive layer, and the second electrode is
substantially reflective and functions as a mirror. The multi-layer
mirror and the second electrode form a microcavity. On a front surface of
the substrate is a light modulation thin film. The light modulation thin
film can be any one of: a cut-off color filter, a band-pass color filter,
a brightness enhancing film, a microstructure that attenuates an emission
spectrum at an angle at which there is a perceived color change, or a
microstructure that redistributes wavelengths so the outputted emission
spectrums have the same perceived color.