A display device includes an optical region containing a plurality of pigment grains. Each of the plurality of pigment grains formed by a plurality of pigment molecules encapsulated in an inorganic material, and each of the plurality of pigment grains has a grain size not greater than 70 nm....http://www.google.com.au/patents/US7397614?utm_source=gb-gplus-sharePatent US7397614 - Display device
