Reflection is the change in direction of light at the interface of two media, causing it to return to its original medium.
- Diffuse reflection occurs on irregular (or unpolished) surfaces. Light is reflected in several directions.
All unpolished surfaces, such as a table, cause diffuse reflection. It is impossible to get a clear image when observing an object on this type of surface.
- Specular reflection is the regular reflection of light. Unlike diffuse reflection, it can only exist if the light rays encounter a perfectly flat or polished surface.
Mirrors, panes of glass or a perfectly still surface of water are examples of surfaces that can produce a specular reflection.
A mirror is generally a polished and metallised glass (pewter, silver, aluminium) or a polished surface (metallic or other) that reflects light.
A flat mirror is a perfectly reflective flat surface.
A curved mirror focuses or diffuses light rays. There are two types of curved mirror:
A convex mirror reflects light outside the curvature of the mirror.
A concave mirror reflects light inside the curvature of the mirror.
In physics, the properties of light rays can be studied using different types of mirror and the various formulae associated with them.
The type of mirror determines the position and movement of the light rays. If you know the properties of mirrors, you can build devices using them.
Flat mirrors are generally found in domestic bathrooms.
Convex mirrors are used, among other things, to ensure safety in car parks and convenience stores.
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Concave mirrors produce inverted images. In everyday life, they are used in car headlights.
