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
Orange (colour) the colour of transformation. A wide variety of colours, ranging from a slightly orange yellow to a deep orange red, all simply called saffron, are closely associated with Hinduism and Buddhism, and are commonly worn by monks and holy men across Asia. In Hinduism, the divinity Krishna is commonly portrayed dressed in yellow or yellow orange. Yellow and saffron are also the colours worn by sadhu, or wandering holy men in India. In Buddhism orange (or more precisely saffron) was the colour of illumination, the highest state of perfection. The saffron colours of robes to be worn by monks were