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Irradiation Illusion
The irradiation illusion is an illusion of visual perception in which a light area of the visual field looks larger than an otherwise identical dark area. It was named by Hermann von Helmholtz around 1867; but the illusion was familiar to scientists long before then; Galileo mentions it in his ''Dialogue Concerning the Two Chief World Systems''.Galileo Galilei, ''Dialogue Concerning the Two Chief World Systems'' (1632), Day 1. It arises partly from scattering of light inside the eye. This has the effect of enlarging the image of a light area on the retina The retina (from la, rete "net") is the innermost, light-sensitive layer of tissue of the eye of most vertebrates and some molluscs. The optics of the eye create a focused two-dimensional image of the visual world on the retina, which then .... References Optical illusions {{optics-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Black And White Squares
Black is a color which results from the absence or complete absorption of visible light. It is an achromatic color, without hue, like white and grey. It is often used symbolically or figuratively to represent darkness. Black and white have often been used to describe opposites such as good and evil, the Dark Ages versus Age of Enlightenment, and night versus day. Since the Middle Ages, black has been the symbolic color of solemnity and authority, and for this reason it is still commonly worn by judges and magistrates. Black was one of the first colors used by artists in Neolithic cave paintings. It was used in ancient Egypt and Greece as the color of the underworld. In the Roman Empire, it became the color of mourning, and over the centuries it was frequently associated with death, evil, witches, and magic. In the 14th century, it was worn by royalty, clergy, judges, and government officials in much of Europe. It became the color worn by English romantic poets, businessmen an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
