thumb|A toy kaleidoscope

A kaleidoscope () is an optical instrument with two or more reflecting surfaces (or mirrors) tilted to each other at an angle, so that one or more (parts of) objects on one end of these mirrors are shown as a symmetrical pattern when viewed from the other end, due to repeated reflection. These reflectors are often enclosed in a tube, usually 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.

thumb|upright=1.2|Internal structure of a typical kaleidoscope

Etymology

The term "kaleidoscope" was coined by its Scottish inventor David Brewster. It is derived from the Ancient Greek word (), "beautiful, beauty", (), "form, appearance" and (), "to look, to examine", hence "observation of beautiful forms". It was first published in the patent that was granted on July 10, 1817.

Brewster thought his instrument to be of great value in "all the ornamental arts" as a device that creates an "infinity of patterns". Artists could accurately delineate the produced figures of the kaleidoscope by means of the solar microscope (a type of camera obscura device), magic lantern or camera lucida. Brewster believed it would at the same time become a popular instrument "for the purposes of rational amusement". He decided to apply for a patent. Unfortunately, the manufacturer originally engaged to produce the product had shown one of the patent instruments to London opticians to see if he could get orders from them. Soon the instrument was copied and marketed before the manufacturer had prepared any number of kaleidoscopes for sale. An estimated two hundred thousand kaleidoscopes sold in London and Paris in just three months. Brewster figured at most a thousand of these were authorized copies that were constructed correctly, while the majority of the others did not give a correct impression of his invention. Because so relatively few people had experienced a proper kaleidoscope or knew how to apply it to ornamental arts, he decided to publicize a treatise on the principles and the correct construction of the kaleidoscope.

Philip Carpenter originally tried to produce his own imitation of the kaleidoscope, but was not satisfied with the results. He decided to offer his services to Brewster as manufacturer. Brewster agreed and Carpenter's models were stamped "sole maker". Realizing that the company could not meet the level of demand, Brewster gained permission from Carpenter in 1818 for the device to be made by other manufacturers. In his 1819 Treatise on the Kaleidoscope Brewster listed more than a dozen manufacturers/sellers of patent kaleidoscopes.

In 1987, kaleidoscope artist Thea Marshall, working with the Willamette Science and Technology Center, a science museum located in Eugene, Oregon, designed and constructed a 1,000-square-foot (93&nbsp;m<sup>2</sup>) traveling mathematics and science exhibition titled Kaleidoscopes: Reflections of Science and Art. With funding from the National Science Foundation, and circulated under the auspices of the Smithsonian Institution Traveling Exhibition Service (SITES), the exhibition appeared in 15 science museums over a three-year period, reaching more than one million visitors in the United States and Canada. Interactive exhibit modules enabled visitors to better understand and appreciate how kaleidoscopes function.

Variations

thumb|Polyangular Kaleidoscope of R.&nbsp;B.&nbsp;Bate (with adjustable reflector angles), as illustrated in Treatise on the Kaleidoscope (1819)

General variations

David Brewster defined several variables in his patent and publications:

  • variations in size (Brewster deemed a length of five to ten inches convenient, for one to four inches he suggested the use of a lens with a focus length equal to the length of the reflectors)

Publications

Cozy Baker (d. October 19, 2010)—founder of the Brewster Kaleidoscope Society—collected kaleidoscopes and wrote books about many of the artists making them in the 1970s through 2001. Her book Kaleidoscope Artistry is a limited compendium of kaleidoscope makers, containing pictures of the interior and exterior views of contemporary artworks. Baker is credited with energizing a renaissance in kaleidoscope-making in the US; she spent her life putting kaleidoscope artists and galleries together so they would know each other and encourage each other.

In 1999, a short-lived magazine dedicated to kaleidoscopes—Kaleidoscope Review—was published, covering artists, collectors, dealers, events, and including how-to articles. This magazine was created and edited by Brett Bensley, at that time a well-known kaleidoscope artist and resource on kaleidoscope information. Changed name to The New Kaleidoscope Review, and then switched to a video presentation on YouTube, "The Kaleidoscope Maker".

  • The Rise and Fall of a Midwest Princess, the 2023 album by Chappell Roan contains the song "Kaleidoscope", which compares love to the unpredictable nature of the kaleidoscope, mentioning them four times.

See also

References

  • Brewster Kaleidoscope Society – organization for kaleidoscope enthusiasts
  • Demonstration of kaleidoscope variants in Shadertoy
  • Kaleidoscope Mirror Designs
  • Kaleidoscope Resource (non-profit)
  • Kaleidoscope Builders' Knowledge Base
  • Shockwave Flash Kaleidoscope (move mouse around it)
  • Kaleidoscope Review V2N1 - an issue of The New Kaleidoscope Review
  • ArtScope - program emitting a visual effect of a kaleidoscope with the number of mirrors from 4 to 98