The science behind the splitting of white light into colours

The Science Behind the Splitting of White Light into Colours

Introduction

The splitting of white light into different colours is a fascinating phenomenon that plays a fundamental role in our understanding of light and colour. This process, known as dispersion, was first studied extensively by Isaac Newton in the 17th century. Newton's experiments showed that white light is not homogeneous, but consists of a range of colours that become visible when the light passes through a prism. This insight laid the foundation for modern optics and colour theory.

Dispersion: The Principle Behind the Splitting

Dispersion is the process by which white light is split into its constituent colours when it passes through a medium such as a prism. This happens because light waves of different wavelengths travel through the prism at different speeds. When light passes from one medium (such as air) to another (such as glass), the speed of the light changes, resulting in the refraction of the light ray. This phenomenon is known as refraction.

How Does Dispersion Work?

The degree of refraction depends on the wavelength of the light: shorter wavelengths (such as violet and blue) are refracted more strongly than longer wavelengths (such as red). This is because the refractive index of the glass (or another transparent medium) varies for different wavelengths of light. In a prism, the different wavelengths of light are each refracted at a slightly different angle, resulting in a spread of colours known as the colour spectrum.