Making eyes see colour changes with optical illusion is a fun way to introduce kids to the phenomenon of colour afterimages. This only works with complementary, or opposing, colours, such as red and green shades, and yellow and blue shades. Modern perception theory assumes that these are two specific channels for vision. Thus staring at one colour will fatigue those specific colour detectors, so that when you look away, you see the opposing afterimage.
- Skill level:
Other People Are Reading
Things you need
- Red, green, yellow and blue paint
- Red, green, yellow and blue magic markers
- Black pen
- White paper
Paint or colour in with marker a large dot on a white piece of paper, in the colour red, and then repeat on separate paper with the colours green, yellow and blue. Very bright or neon colours work best for this experiment.
Stare at the red dot for 20 seconds, then shift your eyes to a white piece of paper, and you should see a green dot. The opposite should occur when you stare at the green dot for 20 seconds.
Stare at the yellow dot for 20 seconds, then shift your eyes to a white piece of paper, and you should see a blue dot. The opposite should occur when you stare at the blue dot for 20 seconds.
Create other optical illusions with these colours to provide fun for children. For instance, colouring or painting a red dot inside a green box will cause a reverse of the colours when the kids shift their eyes to a white piece of paper.
Staring at a bright green cardinal-shaped bird for 20 seconds and then shifting eyes to an empty bird cage drawn on white paper with black ink creates the image of a red or magenta cardinal in the cage.
Tips and warnings
- Different people will have different results depending on individual variations in colour perception. Green may have an afterimage ranging from red to magenta, for instance, and red may have an afterimage ranging from green to blue-green.
- There also will be variations depending on what shade and hue of different colours are used.
- 20 of the funniest online reviews ever
- 14 Biggest lies people tell in online dating sites
- Hilarious things Google thinks you're trying to search for