Kaleidoscope

Kaleidoscope is an optical instrument that presents an ever-changing view for those who look through it. It was invented by Sir David Brewster in 1816 and has since become a popular toy and tool for studying light and symmetry.

History

The kaleidoscope was invented by Scottish scientist Sir David Brewster in 1816 while conducting experiments on light polarization. Its name derives from the Greek words, Kalos (meaning 'beautiful'), Eidos ('form') and Scopeo ('to look at'). Brewster patented his invention in 1817, but due to a fault in the patent, many copies were made without his permission.

Design and Function

A typical kaleidoscope contains two or more reflecting surfaces (usually mirrors) inclined to each other at an angle, so that one or more (parts of) objects on one end of the mirrors are seen as a regular symmetrical pattern when viewed from the other end, due to repeated reflection. The reflectors (or mirrors) are usually enclosed in a tube, often containing on one end a cell with loose, colored pieces of glass or other transparent (and/or opaque) materials to be reflected into the viewed pattern. Rotation of the cell causes motion of the materials, resulting in an ever-changing view being presented.

Uses

While kaleidoscopes are often seen as toys, they also have serious applications. They are used in the fields of physics and psychology to study light and the human perception of symmetry. In the arts, they are used for inspiration and design, and in the spiritual world, they are used as metaphors for the complexity and beauty of the universe.

Variations

There are many variations of the kaleidoscope. Some change the number of mirrors or the angles between them. Others change the objects that are reflected. Some modern kaleidoscopes incorporate electronics, such as LEDs, to enhance the visual effects.

See Also

• Optics
• Symmetry in physics
• Light
• Toy

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  Kaleidoscope tube 1
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  Kaleidoscope construction
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  1819 Brewster - Treatise on the Kaleidoscope fig 39-40 (Kircher - Bradley comparison)
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  Kaleidoscopes
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  Kaleidoscope
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  1819 Brewster - Treatise on the Kaleidoscope fig 18-20
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  1819 Brewster - Treatise on the Kaleidoscope fig 33-36
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  1817 Brewster - Kaleidoscope patent fig 4-5