ZnS Optical Window Explained
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- Felix Glass Co., Limited
- Issue Time
- Oct 10,2026
Summary
This guide covers multispectral ZnS windows: transmission, benefits, coatings, ZnSe comparison and uses for thermal & IR systems.
ZnS Optical Window Explained
Zinc Sulfide (ZnS) is a widely used multi-spectral infrared optical material. ZnS optical windows feature balanced mechanical strength and broadband infrared transmission, commonly deployed for thermal imaging, IR domes and protective windows instead of ZnSe in high-impact environments.
Key Optical & Physical Properties of ZnS Windows
| Parameter | Specification & Notes |
|---|---|
| Transmission Range | 0.4 μm ~14 μm, visible + mid-infrared multi-spectral band |
| Refractive Index @10.6μm | ~2.20 |
| Hardness & Durability | Much harder than ZnSe, impact resistant for harsh environments |
| Limitation | Higher absorption at 10.6μm, not preferred for high-power CO₂ laser |
| Surface Quality | Available up to 20/10 scratch-dig grade |
Available Coating Options
- Broadband multi-spectral AR coating for visible to MWIR range
- DLC diamond-like carbon coating for scratch and moisture resistance
- Single-band AR coating optimized for thermal imaging wavelength
ZnS vs ZnSe Core Difference
- ZnS: tougher, multi-band transmission, for thermal imaging, airborne/ground IR windows, low-power laser
- ZnSe: lower absorption at 10.6μm, soft material, the standard choice for high-power CO₂ laser optics
Typical Applications
- Thermal imaging camera protective windows and IR domes
- Multi-spectral observation optical systems
- Outdoor, airborne and vehicle-mounted infrared equipment
- Low-power infrared laser protective optics and spectroscopy components
Machining Capacity & Quality Control
Felix Glass supplies CVD-grown multi-spectral ZnS optical windows. We can process plano-plano windows, curved domes, with precision polishing and custom AR / DLC coatings. Custom dimensions, drawings and bulk orders are supported.
Datasheet & Custom Inquiry
Share your working wavelength, size and coating requirements to get quotation for ZnS optical windows and domes.
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