The black hole

For us to be able to see anything at all, we need light. If the light visible is white, we can see all the colours of the rainbow.

This experiment is temporarily closed, due to the coronavirus. We hope to be able to open it again soon!

For us to be able to see anything at all, we need light. If the light visible is white, we can see all the colours of the rainbow. When the light reaches the cornea, the light is colourless. We experience colour because our brains tell our senses that information is telling the brain that we can see different colours. And so colours appear different to different people.

The sight receptors are known as rods and cones. The rods and cones can be found in the retina. The rods interpret grey tones, whereas three types of cone register colours. Colours have different wavelengths, and different wavelengths stimulate different cones. There is a point on our retina called the “macula”, which sharpens the images we see. The macula contains a higher number of cones. The optical nerves send signals to the eye saying we can see light, and this is where the impression of colour appears. We can see light with wavelengths between 360-750 nanometres. This is called “visible light”. Infrared and ultraviolet lights are close to the visible light, and can be seen by certain insects.