Explanation

A class of optical materials composed of thin multilayer films and capable of realizing specific optical functions. There are many kinds of optical coating. According to their applications, they mainly include optical reflection film, antireflective (bright) film, absorption film, polarizing film, spectroscopic film, Qiandang filter film, phase film and optical protecting coating. The optical properties of optical coating are based on the interference of light. For a single layer film deposited on the optical surface, when its refractive index is lower than the fundamental refractive index, the result of interference superposition can reduce the surface reflectivity. On the contrary, when the refractive index of the film is higher than that of the matrix, the reflectivity increases. Changing the optical constant and thickness of the film layer, increasing or decreasing the number of layers of the film, can achieve different optical effects.

Classification