# Reflection

## Acoustics

For surfaces large compared to the wavelength of impinging sound, sound is reflected much as light is reflected, with the angle of incidence equaling the angle of reflection.

## Mathematics

A transformation of the x-y plane that moves each point to the opposite side of a fixed line, called its axis, along the line perpendicular to the axis so that the resulting point is the same distance from the axis as the original point.

## Optics

If waves are incident upon a reflecting surface (e.g. mirror, harbour wall, etc.) they will obey the law of reflection which states:

angle of incidence = angle of reflection, where the angles are measured from the surface normal.

### Specular Reflection

When the energy is scattered in only one direction, where the angle of incidence equals the angle of reflection, the scattered energy is generally called a specular reflection. In a specular reflection, most of the energy is concentrated into a very short period of time.

### Diffuse Reflection

When the energy is scattered uniformly in many directions and temporally dispersed, the scattered energy is called a diffuse reflection. In a diffuse reflection the energy is distributed over a longer period of time than in a specular reflection.

Subjects: Physics