A display comprises a light source and an image display panel disposed in
an optical path from the light source. The light source comprises a
primary light source for illuminating a re-emission material which
comprises at least a first nanophosphor material for, when illuminated by
light from the primary light source, re-emitting light in a first
wavelength range different from the emission wavelength range of the
primary light source. The image display panel comprises a first filter
having a first narrow passband or a first narrow absorption band, the
first narrow passband or first narrow absorption band being aligned or
substantially aligned with the first wavelength range. The combination of
a narrow wavelength range emitted by the first nanophosphor material and
the narrow passband or narrow absorption band of the filter allows a
display with high efficiency and a high NTSC ratio to be obtained.