Kaleidoscope
Common misspellings: kaleidescope, kalidoscope, kalaidoscope, kalaidescope, kalidescope
Etymology: Greek kalos beautiful + eidos form + English -scope to look at
The kaleidoscope is a tube of mirrors
with some loose coloured beads
or other small objects. The viewer looks in one end and light enters the other end reflecting
off the mirrors. Typically there are two rectangular lengthways
mirrors. Setting of the mirrors at 45 degrees
creates eight duplicate images, at 60 degrees six, and at 90 degrees
four. As the tube is rotated the tumbling of the coloured beads
causes colour and pattern changes seen by the viewer. Any arbitrary
pattern of beads shows up as a beautiful symmetric pattern. A
two-mirror model will yield a pattern or patterns isolated against
a solid black background, while a three-mirror (closed triangle)
model will yield a pattern that fills the entire field.
Invented by Sir David Brewster in 1816 while conducting experiments on light polarization, it was
patented in 1817. The initial design was made
from a tube in which Brewster placed pairs of mirrors at one end, and pairs of translucent disks at the other end. Between the
two, he placed the beads. Initially intended as a science tool it was quickly copied as a toy.
This article is licensed under the GNU Free Documentation License. It uses material from the Wikipedia article "Kaleidoscope".
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