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Zinc sulfide(ZnS) window

Zinc sulfide(ZnS) window

Zinc sulfide(ZnS) optical window


 Polycrystalline of Zinc sulfide(ZnS)
 Multispectral grade Zinc Sulfide(ZnS)

Other Names

Zinc sulfide window, ZnS window, ZnS FLIR window

Crystal structure


Applicable wave band

0.4um ~ 12um

Melting Point


Growth method

CVD (Chemical Vapor Deposition)

4.08 g/ cm3

Knoop Hardness

210 kg/ mm2

Absorption coefficient

≤0.15 /cm(including 2 surfaces)

Refractive index (λ=10.6 μm)


Thermal conductivity

0.16 W/cmK

Coefficient of thermal expansion


Maximum size

 Diameter 260mm (Polycrystalline)


Material Standard Size Surface quality
Zinc sulfide(ZnS) window φ10.0mm x 1.0mm
φ20mm x 2.0mm
φ25.4mm x 3.0mm
φ25.4mm x 5.0mm
φ50mm x 1.0mm
φ50.8mm x 3.0mm
12.7 x 12.7 x 3.0mm
25.4 x 25.4 x 3.0mm
Polishing:             Double side optical polished or Epi-polished
Roughness:          Ra<0.5nm, Ra<1nm or Ra<5nm
Size Tolerance:          +/-0.1mm
Thickness Tolerance: +/-0.1mm or +/-0.05mm
Parallelism:           1 minute, 30 seconds, 5 seconds or higher
Surface Finish:      60-40, 40-20, 20-10 or others
Surface Figure:      1/2λ, 1/4λ or higher
Chamfer:                0.25mm × 45°

Zinc sulfide (ZnS) is an excellent Infrared optical window / substrate material. The transmission range of multispectral grade Zinc Sulfide is 0.4um-12um. In this band, it has the advantages of low absorption and low scattering, and it is not easy to deliquesce. Zinc sulfide window Commonly used as the middle and far Infrared window materials. Multispectral Zinc Sulfide (ZnS) can be used as window material in the 3-5um band and as a fairing / head cover material, and as a carrier material in the 7um-12um window band.

Zinc sulfide(ZnS) window is similar to Zinc Selenide(ZnSe) windows and both are commonly used in thermal imaging applications. Excellent transmittance in visible and Infrared band, it is ideal for systems with visible and medium or long wave infrared sensors. ZnS window is with better hardness and more chemically resistant than ZnSe window.

We can customize different size and thickness of Zinc sulfide (ZnS) optical window upon requirements, such as Zinc sulfide (ZnS) round wafer, Square substrate and Cylinder, or Punch holes and other shapes.
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Contact Us

  • Biotain Crystal Co., Ltd.
  • Tel: (+86) 1506 0796 451
  • Fax: (+86) 592 523 6275
  • Email:
  • Work Time ( GMT +8 ):
  •    9 AM ~ 6 PM, from Monday to Friday
  • Main office: NO. 254, Hubin North Road, Xiamen City, Fujian Province, China