réflecteur

Réflecteur is a French word that translates to "reflector" in English. In optics and physics, a reflector is a surface or object that reflects light or other electromagnetic radiation. This reflection can be specular, meaning the light bounces off at a precise angle, or diffuse, where the light scatters in many directions. Reflectors are essential components in a wide range of technologies and natural phenomena.

Common examples of reflectors include mirrors, which are typically made of glass with a reflective coating on the back. Polished metal surfaces also act as reflectors. In everyday life, reflectors are found in bicycle lights, car taillights, and road signs to enhance visibility by returning light back towards the source. In astronomy, large parabolic reflectors are used in telescopes to gather and focus light from distant celestial objects.

The principle of reflection is governed by the law of reflection, which states that the angle of incidence equals the angle of reflection, provided the surface is smooth. However, even rough surfaces exhibit diffuse reflection. The design and material of a reflector determine its efficiency and the specific wavelengths of radiation it can reflect. Beyond visible light, reflectors are used for other forms of electromagnetic radiation, such as radio waves and infrared.