PHY 2020 Lecture Notes - Lecture 40: Specular Reflection, Diffuse Reflection, Geometrical Optics
Document Summary
Light has properties of both waves and particles. In figure below, the light is both reflected and refracted by the window. Reflection may be stated as bounce back . If a surface is planar on the scale we observe, it will allow orderly (or specular) reflection. When we draw a line perpendicular to the flat surface, we can measure angles of the incoming and outgoing rays with respect this 90 degree line, the normal. A surface that produces specular reflection is higly polished. The speed of light in vacuum is c = 2. 99792458 x 10^8 m/s. The index of refraction of an material is the ratio of the speed of light in vacuum (c) to the speed of light in the material (v: n= c/v. Light always travels more slowly in material than in vacuum, so: n > 1. Angles are measured with respect to the normal. Reflection: the angle of reflection is equal to the angle of incidence.