MgF2 is commonly used in AR coating for lenses, windows and beam splitters because of its almost ideal refractive index (1.35 @550nm) and high durability.
Single layer AR coating is available for almost any angle of incidence and any wavelength from UV to IR. A layer of MgF2 on a glass of Fused Silica substrate reduces surface reflectance to < 1.5% per surface over a wide range.

V-coating is multilayer AR coating that reduces surface reflectance < 0.25% at 0 degree AOI or < 0.75% at 45 degree AOI at the chosen single wavelength. Using V-coating on Fused Silica substrate can provide exceptionally high external transmittance. Rainbow Research Optics is producing V-type AR coating for any wavelength from 193nm to 2940nm.

These Double-V AR coating is providing the performance of V-coating for two selected wavelengths. This coating is useful for optics that must transmit a visible alignment laser as well as NIR process beam (ex. Nd:YAG laser). Double-V coating provides an average reflectance <0.25% for NIR region and <0.5% for visible region at normal AOI.

This BBAR coating provides the minimum reflectance for wide spectral range. Average reflectance losses are reduced to <0.5% per surface for specified wavelength range. Due to the high number of layers, this coating are more sensitive to incident angle than the single layer AR.

This coating is optimized to give >99% of reflectance at specific laser wavelength. It may be used as a rear cavity reflector at o deg AOI, extra cavity used in beam delivery or turning at 45 deg incident angle. In addition to the standard laser line coating, we offer broadband high reflector for multi-spectral application. It is more efficient than any metal coating and may be used with lasers or broadband sources.

Partial reflective coating is used as laser output couplers at 0 deg AOI. An appropriate output coupler should be selected to maximize the output power/ energy ratio. Rainbow Research Optics offers high quality laser cavity coating for low scattering. Also, this coating is used as extra cavity beam dividers at 45 deg AOI for the specific wavelength. They have an AR V-coating applied to the rear surface.

Edge pass coating is characterized by an abrupt change between a region of transmittance and reflectance. A long wave pass coating reflects shorter wavelengths and transmits longer wavelength. A short wave pass coating reflects longer wavelengths and transmit shorter wavelengths. Cut-on/off wavelength is the wavelength at which the transmission is 50% of its peak value. A common use for this coating is to combine them with a filter or detector response in order to define a wavelength range.

Beam splitters are used to separate or combine two beams of light. Plates are used for most laser applications as they exhibit low absorption. Cubes are convenient, protected form for low power applications. Polarizing beam splitter coating provide an extremely efficient method of driving a randomly polarized incident laser beam into the "S" and "P" components of the beam for specific wavelength or wavelength range.

Metallic coating has lower peak reflectance, mechanical durability and damage threshold than dielectric coatings. The advantages of metallic coating are low cost, extremely broadband performance and insensitivity to input angle of incidence and polarization.