BIOTAIN CRYSTAL > Substrate Materials > Optical windows > Product Information > Next :Sodium Chloride(NaCl) window

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

0.37μm ~ 13.5μm

Melting Point


Growth method

CVD (Chemical Vapor Deposition)

4.08 g/ cm3

Knoop Hardness

210 kg/ mm2

Absorption coefficient

≤0.02 /cm at 3.8μm

Refractive index

2.192 at 10.6 μm

Thermal conductivity

16.7 W/mK at 29.7K

Coefficient of thermal expansion

6.6×10-6/℃ at 273K

Maximum size

 Diameter 260mm (Polycrystalline)

Material Standard Size Surface quality
Zinc sulfide(ZnS) window
(Ordinary grade)
(Multispectral grade)
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 5~10nm or Ra<1.5nm
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 (scratch-dig)
Surface Figure:      1/2λ, 1/4λ or higher
Chamfer:                0.25mm × 45°
Coating:                 Upon requirements

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.
Send Inquiry Online

For more information, please feel free to send us an Online Inquiry or Email us.

Contact Us

  • Tel: (+86) 1506 0796 451
  • Fax: (+86) 0597 2212602
  • Email:
  • Work Time ( GMT +8 ):
  •    9 AM ~ 6 PM, Monday to Friday
  • Main office: A7, No. 501, Denggaoxi Road, Xipi street, Xinluo District, Longyan, Fujian, China