Color reflected color depends upon the viewing angle. Numerous scientists have carried out research in butterfly wings and beetle shells, including Isaac Newton and Robert Hooke. Since 1942, electron micrography has been used, advancing the development of products that exploit structural color, such as "photonic" cosmetics. Color Color (American English), or colour (Commonwealth English), is the characteristic of human visual perception described through color "categories", with names such as red, orange, yellow, green, blue, or purple. This perception of color derives from the stimulation of cone cells in the human eye by electromagnetic radiation in the visible spectrum. Color categories and
Norwegian Judo Federation Norwegian Judo Federation The Norwegian Judo Federation ( - "NJF") is the national federation of judo in Norway. The chairman is Vibeke Thiblin (since 2009) and the deputy chairman is Harald Monsen. The Norwegian Judo Federation was founded in 1967. The organisation's headquarters are in Oslo. It is an affiliate of the International Judo Federation. In 2002 the Norwegian Judo Federation started training Afghan judokas under an exchange program with the Afghan Judo Federation established that year with the federation slogan "Judo for Peace". What began as a modest effort took on a big scale as increasingly more Afghan children