        MyCTMainForum  Reflection and refraction

Optics index               The Fresnel equations and Snell's law are used to calculate the reflection and refraction that occurs at an interface of two materials when light falls on it at a given angle. Brewster's angle and the angle of total internal reflection (critical angle) are also given (as appropriate).              Index a Index b Angle α degrees (°) milliradians radians grad arcseconds arcminutes circles Angle β degrees (°) milliradians radians grad arcseconds arcminutes circles Reflection (s) :1 ppm :2 :5 :10 % (:100) :1 against Reflection (p) :1 ppm :2 :5 :10 % (:100) :1 against Brewster's angle degrees (°) milliradians radians grad arcseconds arcminutes circles Critical angle degrees (°) milliradians radians grad arcseconds arcminutes circles   Enter the refractive indices of the materials a and b, and the angle (to normal) of the beam in material a. For reference, at 589 nm air has an index of ~1.0003, water of 1.33, acrylic of 1.48, glass of ~1.5, polycarbonate of 1.6, and diamond of 2.4. Refractive index is wavelength-dependant.
The calc gives the (refracted) angle in material b, the reflection of the two different polarizations (p is in the plane of the diagram), as well as Brewster's angle and the angle of total internal reflection (if appropriate).          