Kaleidoscope

A kaleidoscope is a tube of mirrors containing loose colored beads, pebbles or other small colored objects. The viewer looks in one end and light enters the other end, reflecting off the mirrors. Typically there are two rectangular lengthwise mirrors. Setting of the mirrors at 45° creates eight duplicate images of the objects, six at 60°, and four at 90°. As the tube is rotated, the tumbling of the colored objects presents the viewer with varying colors and patterns. Any arbitrary pattern of objects shows up as a beautiful symmetric pattern because of the reflections in the mirrors. A two-mirror model yields a pattern or patterns isolated against a solid black background, while a three-mirror (closed triangle) model yields a pattern that fills the entire field.

For a 2D symmetry group, a kaleidoscopic point is a point of intersection of two or more lines of reflection symmetry. In the case of a discrete group the angle between consecutive lines is 180°/"n" for an integer "n"≥2. At this point there are "n" lines of reflection symmetry, and the point is a center of "n"-fold rotational symmetry. See also symmetry combinations.Modern kaleidoscopes are made of brass tubes, stained glass, wood, steel, gourds and most any other material an artist can sculpt or manipulate. The part of the kaleidoscope which holds objects to be viewed is called an object chamber or cell. Object cells may contain almost any material. Sometimes the object cell is filled with liquid so the items float and move through the object cell with slight movement from the person viewing.

Etymology

First attested 1817 in English, the word "kaleidoscope" derives from the Greek "καλός" ("kalos"), "beautiful" [ [http://www.perseus.tufts.edu/cgi-bin/ptext?doc=Perseus%3Atext%3A1999.04.0057%3Aentry%3D%2352841 Kalos, Henry George Liddell, Robert Scott, "A Greek-English Lexicon", at Perseus] ] + "είδος" ("eidos"), "shape" [ [http://www.perseus.tufts.edu/cgi-bin/ptext?doc=Perseus%3Atext%3A1999.04.0057%3Aentry%3D%2330867 Eidos, Henry George Liddell, Robert Scott, "A Greek-English Lexicon", at Perseus] ] + "σκοπέω" ("scopeο"), "to look at, to examine" [ [http://www.perseus.tufts.edu/cgi-bin/ptext?doc=Perseus%3Atext%3A1999.04.0057%3Aentry%3D%2395112 Skopeo, Henry George Liddell, Robert Scott, "A Greek-English Lexicon", at Perseus] ] [ [http://www.etymonline.com/index.php?search=kaleidoscope&searchmode=none Online Etymology Dictionary] ] .

History

Known to the ancient Greeks, it was reinvented by Sir David Brewster in 1816 while conducting experiments on light polarization; Brewster patented it in 1817. His initial design was a tube with pairs of mirrors at one end, and pairs of translucent disks at the other, and beads between the two. Initially intended as a science tool, the kaleidoscope was quickly copied as a toy. Brewster believed he would make money from his popular invention; however, a fault in the wording of his patent allowed others to copy his invention.Fact|date=August 2008

In America, Charles Bush popularized the kaleidoscope. Today, these early products often sell for over $1,000.Cozy Baker collected kaleidoscopes and wrote books about the artists who were making them in the 1970s through 2000. Baker is credited with energizing a renaissance in kaleidoscope-making in America. In 1997 a short lived magazine dedicated to kaleidoscopes called Kaleidoscope Review was published covering artists, collectors, dealers, events, and how-to articles.

Craft galleries often carry a few, while others specialize in them and carry dozens of different types from different artists and craftspeople.

Kaleidoscopes are related to hyperbolic geometry.

Background

For some background on the geometry of the kaleidoscope, see Reflection group.

ee also

* Teleidoscope
* Kaleidoplex

References

External links

* [http://artineck.googlepages.com/12inHU2.htm 12 in HU, moving interactive kaleidoscope]
* [http://www.mentalfx.com/kaleidoscope-dvd/index.html Kaleidoscope DVD]
* [http://finitegeometry.org/sc/16/kal/ Literary and Philosophical Remarks] .
* [http://www.thebigcamera.com.au/Kaleidoscope.html Kaleidoscope History]
* [http://www.kaleidoscopesusa.com/makeAscope.htm How to make a Kaleidoscope ]
* [http://www.kaleidica.com Digital Kaleidoscope] the Kaleidica
* [http://www.waynesthisandthat.com/kaleidoscopes2.htm Kaleidoscope Mirror Designs]
* [http://www.Whizical.com/KalProg.htm Kaleider] Digital Imagery
* [http://www.photoechoes.com/ PhotoEchoes] Digital Kaleidoscope