Transmission with Refraction
Light bends by the physics principle of least time, a consequence of Huygens’ Principle
- light travels from point A to point B by the fastest path
- when passing from a material of index n1 to one of index n2 Snell’s law gives the angle of refraction:n1 sin ?1 = n2 sin ?2where ?1 and ?2 are the angles from perpendicular
When traveling into a denser material (larger n), light bends to be more perpendicular (eg air to water) and vice versa
- light travels further in the faster material
- if the indices are the same the light doesn’t bend
When traveling into a less dense material total internal reflection occurs if ?1>sin-1(n2/n1)