Shortwave Pass Thin Film Coatings

Thin film coatings are extremely thin layers of materials (such as TiO2, SiO2, MgF2, gold, aluminum etc…), which can be applied to the surface of a substrate like glass, metal or germanium, to effect a change in its optical properties. Effects such as reflection, refraction, anti reflection and conductivity can be produced and modified by expert calibration of the number of layers and the respective thicknesses of the thin film coatings in relation to the incidental wavelengths of light.

Shortwave Pass Thin Film Coatings (SWP Thin Film Coatings)

Reynard  Corporation provides thin film Shortwave Pass Filter Coatings for  commercial, aerospace and military applications. These Shortwave Pass  (SWP) coatings can either be applied to the high quality optical  components and substrates that Reynard also supplies, or to  customer-provided substrates.

Shortwave Pass  (SWP) filter coatings are designed for wavelength selection; that is,  to allow the transmission of relevant shorter wavelengths while  blocking or reflecting the longer wavelengths.

Examples of Reynard Filters with Shortwave Pass (SWP) Filter Coatings

• Visible Shortwave Pass Filters (SWP Filters – Visible): Wavelengths  shorter than the 50% “cut on” value for these Visible SWP filters are  transmitted, with longer wavelengths being reflected. The transmission  extends to about 0.45 times the 50% “cut on” point and reflects out to  approximately 1.34 times the 50% “cut on” point. These Shortwave Pass  filters can be supplied for all wavelengths, and applications include  color separators or color combiners and spectral order sorters.

• Infrared Shortwave Pass Filters (SWP Filters – Infrared, or SWIR Filters): These  Infrared Short Wave Pass filters transmit wavelengths shorter than  their 50% “cut on” values and reflect longer wavelengths. The  transmission extends to around 0.35 times the 50% “cut on” point and  reflects out to approximately 1.5 times the 50% “cut on” point. These  filters can be supplied for all wavelengths. Applications for these  Shortwave Pass filters include color sorting or color combining, and  use as emission filters in fluorescence applications.

Shortwave Pass (SWP) filter coatings can be engineered and supplied by  Reynard Corporation for all wavelengths, from UV (Ultraviolet) through  the Visible, IR (Infrared) and Far Infrared bands.

Shortwave Pass (SWP) Coating Process

Our thin film coating facility has 21 vacuum chambers, ranging from an 18” bell jar to a 54” fully automatic box coater, all in a 4000 square foot Class 1000 clean room. Processes include electron beam, ion-assisted and resistance source deposition. We have the capability to coat virtually any size and shape up to and including substrates 50” in diameter.

Available substrates include:

• Alon
• BK-7 (borosilicate crown glass)
• Calcium Fluoride (CaF2)
• Fused Silica
• Germanium (GE)
• KRS5 ( Thallium Bromo-Iodide)
• Sapphire
• Magnesium Fluoride (MgF2)
• Silicon (Si)
• Zinc Selenide (ZnSe)
• Zinc Sulfide (ZnS)
• Or as provided by the customer.

Coating materials include:

• Copper (Cu)
• Gold
• Hafnium Oxide (HfO2)
• ITO (Indium Tin Oxide)
• Magnesium Oxide (MgO)
• Nickel (Ni)
• Silicon Monoxide (SiO)
• Silver
• Titanium Dioxide (TiO2)
• Tantalum Oxide (Ta2O5)
• Zirconium Oxide (ZrO2)
• And many more…

Custom Coating Services

At  Reynard, over 80% of our business is custom. Our Shortwave Pass (SWP)  coatings can be engineered and customized for your particular  application, and in addition we have one of the largest and most  comprehensive selection of standard and stock precision optical  components in the world. Reynard Corporation is the leading global  supplier of optical components to the aerospace, commercial and  military markets. We take pride in meeting and exceeding our customers’  expectations in concept, design, engineering and fabrication.

Click here to request a quote.

Reynard Corporation operates per Military Specification Mil-I-45208A.