infrared

Everyday

1. Infrared is a kind of light that our eyes cannot see, just beyond red light; we feel it as heat. tree →
2. Infrared things use or show this light, like infrared cameras that see warm bodies in the dark, or TV remote controls. tree →

In the lessons

In science lessons on light, heat and the electromagnetic spectrum; in everyday life remote controls, motion sensors and thermal cameras use it. Phrases: «infrared light», «infrared camera», «infrared sensor».

Examples

• Your TV remote sends infrared light. tree →
• Infrared cameras can see animals at night by their warmth. tree →
• We can't see infrared, but we can feel it as heat. tree →
• Snakes called pit vipers can sense infrared. tree →
• The burglar alarm uses an infrared sensor. tree →
• The Sun gives off infrared as well as visible light. tree →
• Infrared photos show warm things as bright colours. tree →
• Firefighters use infrared cameras to find people in smoke. tree →

Note

Sometimes written infra-red. «Infra» means below: its energy is below red light. Ultraviolet is on the other side, beyond violet. Infrared is not dangerous like ultraviolet in ordinary amounts.