1. KaleidoscopeThe beauty of mirrors By: Cheng Wei Loon 2A1 04

2. Introduction A kaleidoscope is a circle of mirrors containing loose, coloured objects such as beads or pebbles and bits of glass As the viewer looks into one end, light entering the other end creates a colourful pattern, due to the reflection off the mirrors The word "kaleidoscope" is derived from the Ancient Greek words: beauty, shape and tool for examination — hence "observer of beautiful forms."

3. How it works Kaleidoscopes operate on the principle of multiple reflection, where several mirrors are attached together Typically there are three rectangular lengthwise mirrors Setting the mirrors at: 45° creates eight duplicate images of the objects Six at 60° Four at 90°

4. How it works As the tube is rotated, the tumbling of the coloured objects presents the viewer with varying colours and patterns Any arbitrary pattern of objects shows up as a beautiful symmetrical pattern created by 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.

5. History Sir David Brewster began work leading towards invention of the kaleidoscope in 1815 when he was conducting experiments on light polarization but it was not patented until two years later His initial design was a tube with pairs of mirrors at one end, pairs of translucent disks at the other, and beads between the two

6. Teleidoscope A teleidoscope is a kind of kaleidoscope, with a lens and an open view, so it can be used to form kaleidoscopic patterns from objects outside the instrument, rather than from items installed as part of it It was invented by John Lyon Burnside III in 1970

7. Advantages of Teleidoscope The lens at the end of the tube is not an optical requirement, but protects the internals of the teleidoscope A spherical ball lens is often used Advantage: It will not press flat against the object being viewed, which would block all light and result in no image being seen

8. Modern Kaleidoscopes Made of brass tubes, stained glass, wood, steel, gourds and almost any other material an artist can sculpt or manipulate The part of the kaleidoscope containing objects to be viewed is the 'object chamber' or 'object 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

9. How to make a kaleidoscope http://www.wonderhowto.com/how-to-make-fun-kaleidoscope-281598/

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