Broadband AR Coatings for LWIR (8–14 µm)

High-performance coatings applied in long-wave infrared systems such as thermal imaging and environmental sensing. These coatings significantly reduce reflection losses in high-index materials, improving overall system sensitivity and performance.

Typical substrates: Germanium (Ge), Zinc sulfide (ZnS), and Silicon (Si)

For optimized designs, very low residual reflectance can be achieved:
R < 0.5% at normal incidence (0°) for silicon substrates and T > 97.7% with double side coating
Ra < 0.6% (8–12 µm) and Ra < 0.8% (12–14 µm) for angles of 0–27°

Coating Function	AR
Design Wavelength (λ)	8-14 um
Angle of Incidence (AOI)	0°
Polarization	Unpolarized
Operating Temperature	-40°C to +85°C
Material	Ge
Refractive Index (n2325.5)	3,99735
Clear Aperture	≥ 90% of diameter or custom
Coating on Front Side	AR
Reflectance (R)	Ra <0.5%
Thermal Stability	–40 °C to +85 °C (no degradation) (MIL-C-48497A, ISO 9022-2)
Humidity Resistance	24 h @ 95% RH, 40 °C (MIL-C-48497A, ISO 9211-3)
Adhesion	Tape test, no peeling (MIL-C-48497A, ISO 9211-4, ASTM D3359)
Temperature Cycling	–40 °C to +85 °C, 10 cycles (MIL-STD-810H, ISO 9022-2)
Chemical Resistance	Acetone, IPA, no delamination (MIL-C-48497A, ISO 9022-5, ISO 9211-4)

Broadband Antireflection Coatings for IR

broadband-ar-coatings-for-mvir-3–5 µm.avif

Broadband AR Coatings for MWIR (3–5 µm)

Technology

Plasma Ion Assisted Deposition (PIAD)

Plasma Ion Assisted Deposition (PIAD) is a technology that combines ion/plasma treatment with electron beam evaporation (or other PVD methods) to modify film growing dinamics and to get desired film properties which are impossible to achieve by conventional PVD methods. It is used to deposit conformal optical coatings with high densities on complex surfaces, hard coatings of compound materials, and adherent metal coatings.