How Kaleidoscopes Work

At the most basic level, a kaleidoscope is made of two or more mirrors or reflective surfaces positioned at an angle to each other, usually forming a V-shape or a triangle. A tubeorcase -- often looking like a spyglass -- is the body surrounding the mirror assembly. A collection of objects is positioned at one end of the mirrors, and there's an eyehole at the other end.

What you see when you look through that eyehole will never be exactly the same twice! While the container holding the objects is usually as large as -- or larger than -- the kaleidoscope tube, only the portion of the objects that fall within the space of the triangle within the object holder is reflected.

Consider a pizza cut into wedge slices. A single slice might represent the objects that are displayed in the vee-shaped or triangular area of a kaleidoscope. However, if you put that slice of pizza between two angled mirrors, what you'd see would look almost like a whole pizza made up of numerous reflections of that one slice, side by side.

Basic geometry tells us that a circle, like a complete pizza, is 360 degrees around. Each pizza slice or triangle in the kaleidoscope is a portion of that. The fatter the wedge, the wider the angle is at its point; the thinner the wedge, the smaller the angle. The size of the angle determines how many times that slice is reflected. For example, if your slice is one-fourth of the whole pizza, the angle is 90 degrees. In a kaleidoscope with two mirrors, that pizza slice appears four times in the image at the end of the kaleidoscope. If the slice is half that size -- a 45-degree angle -- it's reflected eight times in the image [source: Kohler]. The smaller the slice, the more times it appears.

Fortunately, the image in the average kaleidoscope is far more interesting than pizza. Even the simplest collection of ordinary buttons, beads or glass pieces is transformed into an intricate and beautiful design when a kaleidoscope does its work. This is due in part to the principle of symmetry. If you draw a line down the center of a symmetrical object, the halves on either side of the line are the same. Commonly, you'd say that they're mirror images of each other. In a kaleidoscope, each repeated image is symmetrical in relation to the image beside it. The more precisely the mirrors or reflective surfaces are joined together, the more precise the resulting symmetrical images will be.

In a two-mirror kaleidoscope, a 30-degree wedge has 11 reflections [source: Staub]. If the original wedge is at the very top (at 12 o'clock on a clock face), the reflections on its right and left (11 o'clock and 1 o'clock) are the first reflections of the original image. Given the way light hits a mirror and reflects away at the same angle, a blue bead placed at the right-hand edge of the original wedge would appear in the same position on the left-hand edges of the first set of reflections. The reflections at 10 o'clock and 2 o'clock are the second set of reflections; the blue bead appears on the right-hand edges of these wedges.

The third set of reflections (9 o'clock and 3 o'clock) shows the blue bead back on the left-hand edge. The blue bead appears on the right-hand edge in the fourth set of reflections (8 o'clock and 4 o'clock). And it appears on the left-hand edges in the fifth set of reflections (7 o'clock and 5 o'clock). The final reflection (6 o'clock) shows the bead once again on the right-hand edge. The way the object reflections move from side to side and combine with others in this symmetrical dance form the patterns that make kaleidoscopes so delightful.

The two-mirror construction creates a design of wedge reflections filling 360 degrees with a black background. Three or more mirrors will result in a design that fills the entire space with even more intricate geometric patterns and their seemingly endless reflections. For example, three mirrors create a series of complex triangular reflections. The mirror angle affects the pattern.

Because the objects in the kaleidoscope move -- usually after you shake them or rotate the object container -- they never are arranged exactly the same way a second time, and no two designs will ever be perfectly identical.

Want to know how this ingenious device came to be? Then read on.

Evidence shows that pieces of polished obsidian (a volcanic glass) were used as mirrors as long as 8,000 years ago [source: Enoch]. Mirrors reflected sunlight or fire in early lighthouses, and there's a record of a possible optical illusion by an ancient Egyptian magician involving a mirror. By the 17th century, the "Hall of Mirrors" -- an ornate corridor with 357 mirrors -- in the Palace of Versailles became a display of French glory. Mirrors also may have helped achieve symmetry in planning ornamental gardens, a step in the direction toward the kaleidoscope.

By the early 19th century, the stage was set for this new device that turned utilitarian mirrors into fun. In the early 1800s, scientists were exploring concepts of light and optics, while improving technologies also allowed the middle classes to devote more time and resources to leisure activities. Devices known as philosophical toys became a form of amusement that did double duty by sharing scientific advances while entertaining the masses.

In 1816, Scotsman Dr. David Brewster was the first to arrange mirrors and objects in a tube and call it a kaleidoscope. Not just a toy, the device also was intended for use by designers and artists, who might be inspired by the beautiful patterns they could create. Brewster patented his invention in 1817.

Kaleidoscope technology made its next leap forward in 1873. That's when American Charles Bush patented several improvements. He added a stand that could be easily disassembled for portability and a rotating wheel to expand the variety of possible designs. Perhaps Bush's most ingenious advance, though, came in the form of special ampoules. An ampoule is a small, sealed glass vial often holding medicine. Tiny ampoules already had been used as objects in some kaleidoscopes. Bush's patent specified ampules with "two or more liquids of different densities or character, or a liquid with a solid or solids." Bush wrote that the liquids within the ampoules should be unable to mix and each would have its own color. This allowed for even more intricate designs [source: Bush].

Entertainment hit the high-tech big-time over the next century. Radio, motion pictures and television pushed kaleidoscopes mainly into children's hands. That is, until an exhibition at Maryland's Strathmore Hall Arts Center in 1985 included more than 100 kaleidoscopes and drew great interest. Establishment of the Brewster Kaleidoscope Society for kaleidoscope enthusiasts soon followed.

Today, the society lists about 125 kaleidoscope artists among its members. They're busily turning the philosophical toys into unique art. On the next page, we'll take a look at the wide range of materials and types of kaleidoscopes available today. You'll see that kaleidoscopes have come a long way in 200 years.

Today, Dr. Brewster's invention is available in a wide range of prices -- from a dollar or so for cheap party favors to tens of thousands of dollars for hand-crafted collectibles. The materials used to make the bodies vary widely accordingly. Some common materials used include cardboard, wood, metals (brass is common), glass (clear glass, stained glass and more) and plastic.

You're probably most familiar with the tube-shaped kaleidoscope, which resembles a spyglass or telescope. However, barrel shapes are common as well. In addition, some are conical, and other free-form designs defy description. Some are fitted with stands and others are hand-held. You could buy a miniature kaleidoscope made into a necklace or a two-sided kaleidoscope that allows you and a friend to view the same design from opposite sides.

When you look into a kaleidoscope, there's no telling what objects could be making the striking pattern you see. Even boring, everyday items can become exciting art when introduced to a kaleidoscope. Typical objects might include colored glass pieces, beads,buttons, ribbon pieces, ampoules (as described previously), confetti, glitter, "found" items and natural items (like feathers or flowers).

Some special kaleidoscopes, called teleidoscopes, don't include objects at all. You look through clear glass at the end of the tube and see a design created by reflections of your own surroundings.

Object holders can be several different designs. Most common are cells -- thin, round boxes or chambers that have enough room for the items to move. Sometimes the objects are suspended in a liquid, but cells are also frequently dry. Object holders even may be tube-shaped. Some cells are built into the kaleidoscope body; others are attached to the outside or slipped through the side. Some are even interchangeable, or they open, allowing the user to add different objects. All of these must be made of a transparent material, like glass or plastic, so that users can view the items inside. There must be some source of light to illuminate the objects; often sunlight or lamplight behind the object holder is enough, but sometimes a light is built into the device.

To add yet more variety, kaleidoscope artisans may introduce different-colored backgrounds. These might be interchangeable glass or plastic disks.

Mirror configurations within the kaleidoscope will help determine what pattern you see when you look through the eye-hole. Two- and three-mirror constructions (making the vee or triangle described previously) are most common. However, kaleidoscope innovators may use tapered mirrors instead of rectangular ones, or a greater number of mirrors aligned in untraditional ways, in pursuit of even more intricate designs. For example, they may be 3-D or umbrella-shaped.

Really, the people who create kaleidoscopes are only limited by their imaginations. There are as many possible kaleidoscope constructions as there are patterns created by the kaleidoscopes themselves! You, too, can join this creative world of kaleidoscope design. Read on to learn how to make your own.

Although kaleidoscopes can be elaborate, collectible pieces of art costing thousands of dollars, you can make your own. Depending what you have on hand, you may not even have to spend a dime to do it. Here's what you need:

To put it all together, follow these steps:

Don't be afraid to experiment. You may discover the next amazing innovation in kaleidoscope design. Like all great artisans, you're only limited by your imagination!

Visit the links on the next page to learn more about kaleidoscopes and other related topics.