Photon

Definition

A photon is a fundamental particle of light that behaves both as a wave and a particle. It is the quantum of electromagnetic energy, including visible light and other forms of radiation.

Related terms

Electromagnetic Spectrum: The range of all types of electromagnetic radiation from radio waves to gamma rays.

Retina:

The layer at the back of the eyeball containing cells that are sensitive to light and trigger nerve impulses that pass via the optic nerve to the brain where a visual image is formed.

Visual Perception: The ability to interpret the surrounding environment by processing information contained in visible light reaching the eye