Reflection by thin layers. In the figure, light is incident perpendicularly on a thin layer of material 2 that lies between (thicker) materials 1 and 3. (The rays are tilted only for clarity.) The waves of raysr and r2 interfere, and here we consider the type of interference to be either maximum (max) or minimum (min). The table below provides the indexes of refraction n, n2, and ng, the type of interference, and the thinlayer thickness L in nanometers. Give the wavelength that is in the visible range. n1 n2 n3 Type L A 1.42 1.54 1.81 min 221

Reflection by thin layers. In the figure, light is incident perpendicularly on a thin layer of material 2 that lies between (thicker) materials 1 and 3. (The rays are tilted only for clarity.) The waves of raysr and r2 interfere, and here we consider the type of interference to be either maximum (max) or minimum (min). The table below provides the indexes of refraction n, n2, and ng, the type of interference, and the thinlayer thickness L in nanometers. Give the wavelength that is in the visible range. n1 n2 n3 Type L A 1.42 1.54 1.81 min 221