A tuned OLED device includes a microcavity structure including a
light-emitting layer for producing light, a semitransparent reflector,
and a reflector layer disposed on opposite sides of the light-emitting
layer, the microcavity structure enhancing on-axis light produced from
the light-emitting layer in at least one particular wavelength to produce
a desired on-axis viewed color while not substantially enhancing on-axis
other wavelengths of such light; and a layer including a color change
medium which is responsive to wavelengths of light shorter than the
particular wavelength by absorbing such shorter wavelengths of light and
emitting light corresponding in color to the particular wavelength,
thereby improving the color of the light produced by the OLED device when
viewed in an off-axis direction.