ZnS Optical Glass | CVD Zinc Sulfide Multi-Spectral IR Substrate - Felix Glass
ZnS Optical Glass
Overview
ZnS optical glass, CVD zinc sulfide, is a widely used multi-spectral infrared optical substrate. Standard CVD ZnS offers excellent transmission across 0.4 μm to 14 μm. Multispectral ZnS is hot-isostatically pressed (HIP) to eliminate scattering losses, delivering clear performance covering visible, near IR and long-wave infrared bands simultaneously.
ZnS has higher hardness than ZnSe and better mechanical stability, making it the preferred dome material for infrared imaging equipment. It is less sensitive to moisture than many other IR materials. The main tradeoff is higher refractive index and weaker transmission beyond 14 μm compared with ZnSe. Multispectral ZnS is critical for systems requiring co-aligned visible and LWIR channels.
Key Optical & Physical Properties
| Transmission Range (Standard CVD ZnS) | 0.4 μm – 14 μm |
|---|---|
| Refractive Index (@10μm) | 2.200 |
| Hardness (Knoop) | 180 Knoop |
| Density | 4.09 g/cm³ |
| Coefficient of Thermal Expansion | 7.5 ×10⁻⁶ /K |
| Thermal Conductivity | 0.27 W/cm·K |
Common Optical Components We Fabricate
- Multispectral ZnS hemispherical domes, conical IR domes
- ZnS infrared protective windows, plane substrates
- ZnS spherical lenses, aspheric infrared lenses
- Custom ZnS blanks and shaped multi-spectral optical parts
Coating Options
We provide optimized coatings for ZnS multi-spectral optics:
- Broadband multi-spectral AR coating (VIS + LWIR)
- Single-band IR AR coating for thermal imaging
- DLC Diamond-Like Carbon hard protective coating
- Anti-reflective coating for 3–5μm MWIR window
Typical Applications
- Multi-spectral infrared imaging systems
- Airborne and vehicle-mounted IR sensor domes
- Thermal camera protective windows
- Optical guidance and target tracking optics
- Infrared spectroscopy and observation instruments
Machining Capability
Felix Glass machines both standard CVD ZnS and HIP multispectral ZnS. Surface quality up to 40/20 scratch/dig; surface flatness λ/8 @632.8nm. We produce precision domes with tight wall-thickness tolerance and excellent concentricity. Round, square and custom contour ZnS optics are available.
Datasheet & Custom Inquiry
Download our ZnS material datasheet for transmission curves and design guidance. Send your drawing, spectral requirement and coating specs for formal quotation.
Request Datasheet & Custom Quote



