What is White

White light can be split to create a rainbow.

How to Use It

Look through the glasses and see the light split into its component colours.

What Science Tells Us

A diffraction grating in the glasses creates interference patterns. The grating contains many fine grooves, which cause light waves to spread out and overlap. At certain angles the colours overlap in just the right way to become brighter. This angle differs only slightly for light of different colours, resulting in dispersion: each colour appears bright in sequence, creating a spectrum.

Things to Try or Ask

 How do other light sources look through the glasses? Try lights in the ceiling, or the flash on your mobile phone.

 Is white a colour? Why or why not? What definition of ‘colour’ are you using?

Finding the Science in Your World

Dispersion can be seen when rain splits white sunlight into a rainbow. Most colour in the world around us starts as white light from the sun.