Kaleidoscopes utilize an internal mirror system.
Renowned Scottish scientist David Brewster invented the kaleidoscope in 1816. There are three factors of the internal mirror system of the kaleidoscope that determine the type of pattern it produces: the shape, number and angle of the mirrors. Additionally, there are designs in construction of the body of the scope that give variety to the patterns created.
Two-Mirror
A two-sided mirror arrangement set at 45-degree angles produces eight reflections
Inside the scope of a two-mirror kaleidoscope are two long, narrow mirrors. The mirrors are joined together with no overlap in a V-shape along their long edge. The tent-shaped mirror set-up extends the length of the scope and produces a pattern in a mandala shape (a symmetrical, circular "snowflake"). The pattern of replication is determined by the angle between the two mirrors. Sometimes, this set up has three mirrors so the mirror-cylinder forms a triangle.
Four-Mirror
A four-mirror kaleidoscope produces a parade effect
Inside the four-mirror kaleidoscope, there are four mirrors joined together along their long edges at 90-degree angles to create a three-dimensional rectangle. Objects viewed through this kind of arrangement are seen in multiples in a parade-like pattern across the diameter of the scope.
Twin Two-Mirror
A Twin 2-Mirror set up produces twin images
A twin two-mirror scope is a cross between the one and four-mirror set-ups. It has two sets of the two-mirror set-ups joined on all sides, resulting in a three-dimensional diamond-shaped tube. This produces a side-by-side twin image of the pattern being viewed.
Wheel
A wheel kaleidoscope has one or more disc-shaped chambers attached to the end of the scope. If the kaleidoscope has more than one wheel, they are stacked together, one in front of the other. The discs contain small objects, such as pressed flowers, beads, crystals, jewels or bits of colored glass. When the discs turn, the objects inside the discs shift and the images change.
Chamber
A chamber kaleidoscope has a fixed case inside the scope. Inside the case are the objects that will be viewed in kaleidoscope image: beads, colored glass or beads. These objects free-fall as the scope is turned.
Liquid Chamber
This type of kaleidoscope is the same as the chamber kaleidoscope, except the objects inside the chamber are suspended in a liquid, usually glycerin.
Refillable
Similar to the chamber kaleidoscope, this type has a chamber inside the scope. However, in this type, the chamber is removable and the objects inside the chamber can be swapped out with other objects.
Teleidoscope
This type of kaleidoscope reflects the images of an object outside the kaleidoscope. When looking at any image through the scope, whatever it is pointed at is reflected, through an arrangement of mirrors inside the scope, into a pattern of multiple images.
