The Physics of Colour

Vocabulary flashcards based on the Physics of Colour lecture, covering wave properties, light interactions, and the biology of sight.

Wavelength

The distance between two successive peaks (or crest to crest) of a light wave, which determines its colour.

Speed of light ($C$)

The rate of motion of crests or troughs, measured at $300,000\,km/sec$.

Period ($T$)

The time between the passage of successive crests of a wave.

Frequency ($V$)

The number of crest passages per unit time.

Amplitude ($A$)

The distance from the level of the crest to the level of the trough.

Reflection

Light bouncing off a surface.

Absorption

Light energy that is taken in by a material.

Scattering

When light rays hit an uneven surface and reflect in many different directions.

Specular Reflection

Occurs on smooth surfaces like mirrors or calm water; light rays remain parallel and create a clear image.

Diffuse Reflection

Occurs on rough surfaces; light hits bumps and scatters in many directions so no clear image is seen.

White light

Light that contains all colours.

Black

The absence of reflection; it occurs when an object absorbs all wavelengths of visible light and reflects nothing.

Vantablack

A material so dark it absorbs $99.96\%$ of light, making 3D objects look like flat 2D holes.

Retina

The area at the back of the eye where reflected light hits after entering through the pupil.

Cones

Special cells in the eye that detect specific wavelengths (Red, Green, and Blue) to perceive colour.