Thin Film Coatings

Coatings Designed for System Reliability

Optical coatings can be the most critical portion of the finished optical component and determine system performance and reliability.  Clear Align has extensive optical coating capabilities, and expertise in producing coatings for advanced applications and harsh environment.  We provide a variety of coating options including the UV, Visible, NIR, SWIR, MWIR, and LWIR portions of the spectrum.

Coating Design

We provide full coating design and verification services in-house. Optical coatings are composed of thin layers of materials including oxides, metals, and rare earth elements designed to enhance the transmission, reflection, or polarization properties of an optical component. The performance of an optical coating is dependent on the process cleanliness, number of layers, layer thickness, and the refractive index difference between layers. At Clear Align we bring an understanding of optical coating theory, material science and manufacturing methodology.  Let us design a coating to meet your program’s needs. 

Automated Cleaning Operations

Clear Align begins with automated ultrasonic cleaning that provides a meticulously surface for optical coatings.  This process is critical to adhesion and long-term reliability. 

Optical Inspection in a Clean Air Environment

After coating we utilized modernized inspection techniques and equipment and inspect to ANSI, MILSPEC, and ISO 10110 standards. This disciplined process eliminates guesswork for inspectors and offer standardized quality control.

Diamond-Like Carbon Coatings (DLC)

Diamond-like carbon coatings (DLC) ensure system performance in extreme environments. Clear Align provides DLC to protect infrared optical systems against salt, fog and sand. Our coating offers an impressive level of stability in addition to high transmission and are qualified for extreme environments. We verify our DLC coating using military and commercial and tests the optical coating by subjecting them to significant mechanical stress. We coat a variety of materials and would be pleased to create a design that meets your individual requirements.

DLC and Hard Coating Highlights

  • Low loss, “hard” coating
  • Overcoats available for scratch resistance & durability
  • Applicable to various substrate materials (BK-7, fused silica, sapphire, etc.)
  • Common reflective metals used, such as gold, silver, and aluminum. Others available.

Notch Filters

Notch Filters are used in a variety of applications including military safety, spectroscopy, microscopy, laser-based instrumentation, and in polarization-controlled devices. Notch Filters selectively reject a portion of the spectrum, while transmitting other wavelengths utilizing multi-layer dielectric coatings to reflect specific wavelengths. Clear Align offers a wide variety of optical filters from in the UV, Visible, NIR, SWIR, MWIR, and LWIR portions of the spectrum.  We also provide multi-band notch filters that enable rejection of multiple narrow bands.

Anti-reflective (AR) Coatings

Decades of design and fabrication of thin film coating has enabled us to develop a broad array of AR coatings. We are able to offer coating services on a wide range of substrate materials and maintain a library of over 2,000 coating fixtures that enable quick-turn programs. Unique geometries are no problem as we design and fabricate tooling in-house as well.  Our thin film design software enables us to create the best coating solution for your needs. We also offer small run prototyping services and in-house qualification testing to be certain that our coatings will be the ideal option for your high-volume.

AR Coatings (400 to 700nm)

  • Residual reflectance < 0.45% on BK-7 glass
  • Residual reflectance < 0.30% on SF-11 glass
  • Wavelength Range from 400nm to 7
  • Other glass substrate materials comparable in refractive index can have AR coatings shown above

AR Coatings (400 to 850nm)

  • Residual reflectance < 0.35% on BK-7 glass
  • Wavelength Range from 400nm to 850nm
  • Other glass substrate materials comparable in refractive index can have AR coating shown above

AR Coatings (900 to 1700nm)

  • Residual reflectance < 0.75% on BAF2 glass
  • Residual reflectance < 0.30% on BK-7 glass
  • Wavelength Range from 900nm to 1700nm
  • Other glass substrate materials comparable in refractive index can have AR coatings shown above

AR Coatings (900 to 1700nm)

  • Residual reflectance < 0.40% on fused silica (SiO2) glass
  • Residual reflectance < 0.75% on Zinc Selenide glass
  • Wavelength Range from 900nm to 1700nm
  • Other glass substrate materials comparable in refractive index can have AR coatings shown above

AR Coatings (3000 to 5000nm)

  • Residual reflectance < 4% on Germanium glass
  • Residual reflectance < 4 % on Silicon glass
  • Wavelength Range from 3000nm to 5000nm
  • Other glass substrate materials comparable in refractive index can have AR coatings shown above

AR Coatings (6000 to 12000nm)

  • Residual reflectance < 6% on AMTIR glass
  • Wavelength Range from 6000nm to 12000nm
  • Other glass substrate materials comparable in refractive index can have AR coatings shown above

AR Coatings (Dual Band: 532/1064nm)

  • Residual reflectance < 0.1% on BK-7 glass
  • Wavelengths @ 532nm & 10640nm
  • Other glass substrate materials comparable in refractive index can have AR coatings shown above

Clear Align routinely fabricates and coats these materials and many others:

  • Acrylic(PMMA)
  • AMTIR
  • Barium Fluoride (BaF2)
  • Brass
  • Bronze
  • Bronze
  • Calcium Fluoride (CaF2)
  • Chalcogenide Glass (IRG, IG)
  • Copper
  • Fused Quartz
  • Fused Silica
  • Gallium Arsenide
  • GASIR (calcogenized glass)
  • Germanium (Ge)
  • Gold (Au)
  • GRIN
  • IRG24
  • IRG26
  • Indium Antimonide
  • Lithium Fluoride
  • MgF2
  • MS Zinc Sulfide (Cleartran)
  • N-BAK1
  • N-BAK4
  • N-BK7
  • Nickel
  • N-SF10
  • N-SF11
  • N-SF2
  • N-SF5
  • N-SF8
  • N-SK11
  • OPK
  • PMMA
  • Polycarbonate
  • Polymers
  • Polystyrene
  • Rexolite (Polystyrene)
  • Sapphire
  • Silicon
  • Silver
  • Zeonex (E48R, 480R, 480)
  • Zeonex Aluminum
  • Zinc Selenide

Qualification and Inspection Available:

  • 8.1 MIL-M-13508C: Military Specification - Mirror, Front Surfaced Aluminized for Optical Elements
  • 8.2 MIL-F-48616: Military Specification - Filter (Coatings), Infrared Interference: General Specification
  • 8.3 MIL-C-48497A: Military Specification - Coating Single or Multilayer, Interference Durability Requirements
  • 8.4 MIL-C-14806A: Military Specification - Coating Reflection Reducing for Instrument Cover Glasses and Lightning Wedges 
  • 8.5 MIL-C-675C: Military Specification - Coating of Glass Optical Elements (Anti-Reflection)
  • 8.6 MIL-PRF-13830B: Optical Components for Fire Control Instruments; General Specification Governing the Manufacture, Assembly, and Inspection
  • 8.7 MIL-STD-810G: Department of Defense Test Method Standard: Environmental Engineering Considerations and Laboratory Tests 
  • 8.7.1 MIL-STD-810C
  • 8.7.2 MIL-STD-810D
  • 8.7.3 MIL-STD-810E
  • 8.7.4 MIL-STD-810G 
  • 8.8 ISO 9211-3: Optics and Optical Instruments - Optical Coatings - Part 3: Environmental Durability
  • 8.8.1 Application Categories and Recommended Tests for Environmental Durability
  • 8.8.2 Thermal Cycle Acceptance Tests According to the Standard
  • 8.9 TS-1888: Technical Specification for Infrared Optical Coatings