Optical coatings are thin layers of oxides, metals, or rare earth metals that change a component’s optical properties. Depending on the type, number, and thickness of treatment layers, optical coatings might alter light transmission, reflection, or polarization. Manufacturers may apply these coatings to glass or polymer lenses, semiconductors, fiber optic devices, and similar substrates.

Evaporated Coatings, Inc. offers an extensive line of optical coatings ranging from anti-reflection coatings that decrease reflection to as low as 0.03% to mirror coatings that enable 99.95% reflection. We also offer stock and custom beam splitter coatings, transparent conductive coatings, and attenuation coatings to suit the full spectrum of industrial optics needs.

Anti-Reflection Coatings

True to their name, anti-reflection (AR) coatings minimize the amount of light that reflects off an optical surface, resulting in improved contrast, heightened transmission, and increased efficiency compared to untreated components. AR coatings are available for narrow and broadband applications, though results vary depending on the incidence bandwidth and angle. For instance, our narrowband AR coatings may eliminate all but 0.03% of front surface reflections, while average results for broadband will be closer to 0.25% of front surface reflection.


ECI’s AR coatings offer excellent adhesion and thermal stability across both standard and non-standard substrates. Our offerings include low-temperature and high-temperature coatings, which we can deposit on parts up to 400 mm in diameter.

Ion Beam Sputtering (IBS) Coatings

Different deposition methods may be appropriate for varying applications. As the most advanced deposition method available from ECI, ion beam sputtering (IBS) yields dense, smooth coatings with superior thermal stability and low thermal shift. IBS thin-film coatings can withstand long-term exposure of temperatures up to 300°C and short-term exposure of temperatures reaching 500°C with a thermal shift of less than 0.5pm/°C.

The IBS deposition method is well-suited to the application of:

  • AR Coatings
  • Dielectric mirror coatings
  • Shortwave pass filter coatings
  • Longwave pass filter coatings
  • Bandpass filter coatings
  • Dichroic filter coatings
  • Notch filter coatings
  • Dielectric beam splitter coatings

Custom Optical Filters

Sometimes stock coatings won’t meet the unique needs of an application. For these customers, we offer high-performance custom filters within the 240-2600 nm range. We draw on the most precise deposition techniques to achieve flawless surface quality on wafers, polymers, fibers, semiconductors, crystals, and other substrates.

When fulfilling custom orders, we work closely with your team to ensure that we use the best materials and deposition techniques to suit your particular application’s substrate, wavelength, angle of incidence, and incident medium.

Mirror Coatings

ECI’s mirror coatings come in three varieties, all of which offer excellent environmental and optical performance. Mirror coatings enhance first or second surface reflection on numerous substrates, including glass, plastic, metal, and fiber optics.

  • Metal mirror coatings. Metal mirror coatings are made from gold, aluminum, or silver and optimized for UV-to-infrared wavelengths. ECI’s metal mirror coatings meet the environmental and durability requirements of MIL-M-13508C, making them suitable for a variety of military, defense, and scientific applications.
  • Dielectric mirror coatings. Dielectric mirror coatings are highly reflective, low-loss broadband coatings that boast more than 99.5% reflection on 248-2500 nm wavelengths. ECI’s dielectric mirror coatings comply with the environmental and durability requirements of MIL-C-48497 (or MIL-F-48616 for coatings on glass substrates).
  • Laser dielectric mirror coatings. For high-power applications requiring high laser damage thresholds, ECI offers laser dielectric mirror coatings, which offer up to 99.95% reflection for even the most strenuous laser applications.

ECI can also deposit proprietary thin-film mirror coatings when needed.

Transparent Conductive Coatings

Transparent conductive coatings maximize both visible light transmission and electrical conductivity for applications such as glass instrument panels, touch displays, heads-up displays, and safety enclosures, among other applications. ECI offers transparent conductive coatings with varying conductivity resistivity and transmission for deposition on glass, semiconductor, and polymer substrates, including temperature-sensitive polymers. Select contrast-enhancing options are also available for clients requiring the utmost clarity and transmission.

Transparent conductive coatings are most common in security, military, medical, and aerospace settings, though they may be useful in any application that requires a see-through conductive surface.

Beam Splitters

Beam splitters separate light into two component beams based on wavelength, intensity, or polarization. The transmitted beam passes through, while the reflected beam of light does not. Beam splitters offer an ideal solution for imaging, sensors, and measurement across a wide range of industries.

ECI offers metal and dielectric beam splitter coatings optimized for specific reflection and transmission ratios, wavelength regions, angles of incidence, polarization states, incident media, and temperature sensitivities.

Standard designs include 50/50, 30/70, and 5/95 ratios of reflectance and transmittance. ECI also designs low-polarization beam splitters and beam splitters with custom AR coatings on the entrance or exit faces.

Attenuation Coatings

Keeping laser energy levels within safe limits requires attenuation coatings to minimize unwanted energy by decreasing incident light transmission. ECI’s attenuation coatings include standard designs, which absorb and reflect excess light and low-reflection films with very low first or second surface transmission. In both cases, we can tailor transmission values to your specifications, resulting in precisely the degree of attenuation required.

ECI’s high-energy deposition process results in dense, stable attenuation coatings that hold up to the rigors of industrial testing and use. We also offer neutral-density coatings for balanced attenuation across the visible light region. In either case, we match your exact needs regarding size, angle of incidence, and back-reflection.

Metal & Dielectric Depositions

ECI offers free in-house thin film coating design, as well as deposition services for existing proprietary coatings. We will deposit the following metals and dielectric materials in a variety of thicknesses on many common substrates:


  • Silver
  • Gold
  • Chrome
  • Titanium
  • Nickel
  • Tantalum
  • Tungsten
  • Aluminum
  • Platinum
  • Palladium

Dielectric Materials

  • Silicon dioxide
  • Magnesium fluoride
  • Cerium fluoride
  • Hafnium oxide
  • Aluminum oxide
  • Titanium dioxide
  • Tantalum oxide
  • Zirconium oxide
  • ECI # 415

Contact Evaporated Coatings for Stock or Custom Optical Coatings

Evaporated Coatings, Inc. has been a premium supplier of precision optical coatings for over 60 years. Whether you’re searching for a custom thin-film design or a trusted partner to deposit an existing formula, ECI has the expertise to perfect your optical components. To see how we can help, please request a quote today.