To produce a laser light show, white light is split into its constituent colours through refraction. A prism is used to slow down different colours of light by different amounts causing them to bend through different angles. The amount of refraction is dependant on the angle the light hits the prism at. Beyond the critical angle, all the light entering the prism is internally reflected. This total internal reflection is the means by which an optical fibre can transmit information from one place to another.
- This clip is from:
- First broadcast:
- 20 March 2008
This clip could be used to complement the study of wave refraction and the electromagnetic spectrum. Use practical refraction activities to introduce the idea that white light can be divided into different colours, then extending this to cover the wider spectrum. Discuss why only part of the spectrum is visible and compare this to the vision of other animals, and to other means by which different parts of the spectrum can be detected or used. Look in more detail at the use of fibre optics in medicine and communications.