University of Auckland/Department of Physics/Physics 102/Light
Light, or visible light, is electromagnetic radiation of a wavelength that is visible to the human eye (about 400–700 nm).
Light is composed of elementary particles called photons.
LONGER WAVE LENGTH <-----ROYGBIV-----> SHORTER WAVELENGTH
-red has the longest wavelength
-violet has the shorter wavelength
The cone type labeled 420 is often called the short wavelength cone, while the cone type labeled 534 is often called the medium wavelength cone, and the cone type labeled 564 is often called the long wavelength cone.
Humans only have one type of rod and its main purpose is for seeing in low light conditions.
Transverse waves like light waves (and electromagnetic waves) can be polarised. Polarisation is the property of the wave that describes the orientation of the oscillations.