Visible Light
Applied Science: BTEC Level 3 National Extended Diploma, topic 1.7.6
Visible Light
Visible light is used to see the world around us.
Visible light spectrum
- Traditionally, we say that there are seven colours of light in the spectrum.
- Red, Orange, Yellow, Green, Blue, Indigo and Violet.
Uses
- We use visible light to see the world around us and in fibre optics.
Explanation
- We use visible light in optical fibres because it can be totally internally reflected.
- This means that we can transmit signals (information) along optical fibres without the signals (information) getting lost.
Visible Light
The human eye can see visible light. Visible light is a form of electromagnetic radiation. Light is absorbed, reflected or transmitted when it hits an object. This determines whether an object is opaque, translucent and transparent.
Opaque
- Opaque objects either reflect or absorb all light that hits them.
- No light passes through.
Translucent
- Translucent objects transmit light but the rays are scattered.
- We cannot see objects clearly through translucent objects.
Transparent
- Transparent objects also transmit light without scattering the rays.
- We can clearly see objects on the other side of transparent objects.
Test yourself on Visible Light
Which of these are in the 7 colours of the visible spectrum?
Which of these pairs has the highest frequency?
Which of these is a form of electromagnetic radiation?