Optical Coating

Optical coatings are composed of a combination of thin film layers that create interference effects used to enhance transmission or reflection properties within an optical system. The performance of an optical coating is dependent upon the number of layers, the thickness of the individual layers and the refractive index difference at the layer interfaces. The most common types of coatings used on precision optics are: Anti-Reflection (AR) (HEA) Coatings, High Reflective (Mirror) Coatings, Beam splitter Coatings, and Filter Coatings. Anti-reflection coatings are applied to optical elements to maximize throughput and reduce ghosting. High Reflective coatings are designed to maximize reflectance at either a single wavelength or across a broad range of wavelengths. Beam splitter coatings are used to divide incident light into known transmitted and reflected light outputs. Filters are found in a large number of industry applications and are used to transmit, reflect, absorb, or attenuate light at specific wavelengths. Sterling Precision Optics, Inc. offers a variety of Custom Coatings to meet any application need. Optical Coatings are designed for a specific incident angle of light and for a specific polarization of light such as S-polarized, P-polarized, or random polarization. If a coating is designed for light at a 0° angle of incidence, but is used with light at a 45° angle of incidence, the coating will not perform at the stated transmissionreflection specifications. Similarly, coatings are generally designed for randomly polarized light so using S-polarized or P-polarized light with a coating designed for randomly polarized light will again fail to produce the stated specifications.