The zoetrope was invented in the early 19th century.  Pierre Desvignes, a French inventor, brought the concept to France and gave the device its name – formed from the Greek words “zoe,” meaning life, and “tropos,” meaning turning.  The word zoetrope therefore can be taken to mean “wheel of life” or “living wheel.”

The traditional zoetrope consists of a cylinder with slits cut vertically in its sides and a series of sequenced images on its inner surface.  As the cylinder is spun, the viewer looks through the slits to the opposite side of the interior. When viewed in this way,  the images are seen by the eye in such rapid succession that they produce the illusion of motion.

This illusion is created by an optical phenomenon called “persistence of vision” and something called “beta movement.”

“Persistence of vision” refers to the fraction of a second that the eye’s retina retains an image after it has disappeared from view.  The retina perceives a flash of light for a full tenth of a second after it has ended, so if a light flashes every tenth of a second or less, the retina will perceive the light as shining continuously.

“Persistence of vision” is a stroboscopic effect meaning the images you are viewing must be separated by moments of darkness.  The slits function in this manner, simulating flashes of light and creating a kind of strobe effect.  In fact, modern zoetropes often use strobe lights to create the same illusion.

But because the eye is not identical to a camera, and vision is not as simple as light passing through a lens, the brain needs more than “persistence of vision” to be convinced that the images are in motion.

Beta movement, one of the phi phenomena, is the extra piece of the puzzle.  Beta movement is a perceptual illusion in which the brain creates a relationship between two or more still images viewed in succession.  The brain makes the assumption that they are one image which has changed positions, rather than the truth, which is that they are completely separate images.  Beta movement is the result of our brain’s desire to see relationships between consecutive images, regardless of their differences, and make sense of the data provided by the eye in order to construct a coherent understanding of reality.

The concept of the zoetrope is related to other optical devices like the flip book, the thaumatrope, the praxinoscope, the phenakistoscope, and the electrotachyscope, amongst others.

In 1877, he developed the praxinoscope – the successor to the zoetrope. It used a strip of pictures placed around the inner surface of a spinning cylinder. The praxinoscope improved on the zoetrope by replacing its narrow viewing slits with an inner circle of mirrors, placed so that the reflections of the pictures appeared more or less stationary in position as the wheel turned. Someone looking in the mirrors would therefore see a rapid succession of images producing the illusion of motion, with a brighter and less distorted picture than the zoetrope offered, as with the zoetrop one would have to peep through the spinning slits.

Praxinoscope

In 1888, Reynaud demonstrated the device he called Theatre Optique to a small audience, by showing his own, hand painted film called ‘Un bon bock (A good beer). Operating the Optique was considered a complex task, which in turn dissuaded potential buyers. In 1982, Reynaud settled on a contract with the Grevin Wax Museum in Paris, which would see him perform daily screenings, produce regular new films and give away the exclusive rights for his new machine. In 1900, he closed his Theatre Optique, and sunk into depression due to the advancement in  technology at the time (Lumiere Brothers). He destroyed his machines, and threw his hand painted shorts into the river Seine, He died in poverty in 1918.

The description and illustration of parts are adapted from Optical Lanterns and Accessories: How to Make and Manage Them, Including Instructions on Making Slides etc. ed. Paul N Hasluck (Cassell & Co., London/Funk and Wagnalls, New York, c.1901).

The optical lantern, probably more popularly known as "the magic lantern", is an appliance by means of which transaprencies are projected by artificial light upon a screen with the projected image having a diameter generally from thirty to eighty times greater than that of the transparency or slide, whilst the area of the image may be from one thousand to six thousand times as great.

Chinese shadow theatre figures

Shadow play, also known as shadow puppetry, is an ancient form of storytelling and entertainment which uses flat articulated cut-out figures (shadow puppets) which are held between a source of light and a translucent screen or scrim. The cut-out shapes of the puppets sometimes include translucent color or other types of detailing. Various effects can be achieved by moving both the puppets and the light source. A talented puppeteer can make the figures appear to walk, dance, fight, nod and laugh.

Shadow play is popular in various cultures, among both children and adults in many countries around the world. More than 20 countries are known to have shadow show troupes. Shadow play is an old tradition and it has a long history in Southeast Asia, especially in Indonesia, Malaysia, Thailand and Cambodia. It has been an ancient art and a living folk tradition in China, India and Nepal. It is also known in Egypt, Turkey, Greece, Germany, France and the United States.

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