How to… make your own thaumatrope!
Make your very own optical illusion to wow your friends! Remember - if you try this experiment at home you will need the consent and supervision of your parent or guardian.
 |
What you’ll need…
- A piece of card (lighter colours will work better)
- 2 pieces of string about 30cm long each
- Colouring pencils
- A mug or a big circular glass
- A pair of scissors (please ask an adult to help you with these!!)
- Blob of blu-tac or plasticine (optional)
|
Once you’ve gathered all these items together, follow these simple steps to make your own optical illusion…
|
Step 1
Take your mug/glass and place it on your piece of card. Draw a circle using your favourite colouring pencil and the mug as a stencil. |
 |
|
|
| 
|
Step 2
Get an adult to cut round the circle you have just drawn with your scissors. |
|
Step 3
On one side of the circular piece of card draw a birdcage.
On the other side draw a picture of your favourite type of bird.
IMPORTANT: make sure you draw the birdcage upside-down in relation to the bird. |
 |
 |
Step 4
Get a sharpened pencil and pierce through the card on the left and right hand side of the bird/cage. A piece of blue-tac or plasticine placed behind where you are making the holes may make this easier. |
|
Step 5
Fold one of the pieces of string in half and push it through one of the holes on the card, then push the ends of the string through the loop at the other end and pull it tight. Do the same on the other side.
|
 |
 |
Step 6
Hold the thaumatrope far out in front of you with a piece of string in each hand. Twist the strings between your thumb and forefinger until the card spins. This should make it look like the bird is actually in the cage! |
Why does this happen?
The retina of your eye sends visual information back to your brain. An image produced by the retina in response to stimulation lingers for one-tenth to one-twentieth of a second. As the thaumatrope switches the images faster than this it fools your eyes by merging the two separate images into one. This is called "the principle of the persistence of vision” or “retinal retention.”
Things to Try
Why not try this idea with other pictures? Maybe a picture of yourself on the television or a robber behind bars. Even a plate with some food on it… the possibilities are endless, so get your thinking caps on!
You might also like to try making a flip book - see activity sheet 1 - sight.
