Polarization and colour
PERCEIVING COLOURS
Properties of light
Create colourful compositions with polarized light!
Details:
Ages: 5-99
Time: 20 minutes
Learning Outcome: Observe the colours produced by layered pieces of transparent tape through a polarizing filter.
Colour Concepts: A polarizing filter will reveal coloured areas within some transparent media.
Materials:
A mobile phone or Ipad with Color Savvy app (the screens for these devices are polarized)
Polarized filter from the Colour Paddle Set
A piece of 2"x2" thin transparent plastic (can be cut from a disposable food container)
Transparent cello tape (Note: you can try different brands of cello tape and also transparent packing tape to see which produces the best effect)
Instructions:
Layer at least four strips of the transparent cello tape around the transparent square of plastic. Wrap the tape so that both front and back are covered.
Place the plastic wrapped with transparent tape on the white screen of your phone or Ipad, with the Color Savvy app.
Look at the transparent plastic through the polarizing filter from the Colour Paddle set. What do you see?
Rotate the polarizing filter by 90 degrees. What changes?
Vocabulary:
Questions & observations:
More to explore:
Try different brands of cello tape and 2” packing tape to see which produces the best effect. You can cut the packing tape into different shapes to make a fun design.
You can also look at plastic containers through the polarizing filter, especially at bends in the plastic. What do you notice?
Try using 3D glasses from the movie theatre, or polarized sunglasses to do the experiment.
What’s going on?
Polarization is an extraordinary complex topic (!) yet we can use its effect to make colourful compositions. Certain types of objects like polarizing filters, device display screens, plastics, cello tape, allow only certain orientations of light waves to pass through. These create situations where only limited ranges of wavelengths are directed to our eyes, and can result in the perception of various colours.
Find out more:
Check out more polarization activities at the Exploratorium.
This video on Polarizing Cellotape by Educational Innovations presents a similar polarization experiment.
