Material - Zinc Sulphide (ZnS)

Zinc Sulphide (ZnS) is used for manufacturing of infrared IR optics: ZnS windows, ZnS polished domes and ZnS lenses in spectral range (0.4 - 13.5) microns where maximum transmission and lowest absorption is required, and also selected for use where visible alignment is an advantage.

To obtain high transmittance ZnS crystals are grown by Chemical Vapor Deposition process (CVD). CVD Zinc Sulphide is polycrystalline material which is used in the optical components in infrared IR optical devices.

ZnS (Zinc Sulphide) Chemical Vapor Deposition (CVD) material is produced by synthesis from zinc vapour and H2S gas, forming as sheets on graphite susceptors (CVD-ZnS processes). CVD-ZnS has a polycrystalline structure; the grain size of CVD Zinc Sulphide material is controlled to produce maximum strength and machinability.

ZnS (Zinc Sulphide) multispectral grade is then Hot Isostatically Pressed (HIP) to improve the mid IR transmission and produce the visibly clear form. Polycrystal ZnS is available.

Crystaltechno Ltd. produces Zinc Sulfide (ZnS) optical components (plates and domes) from own-grown CVD-ZnS FLIR grade material (FLIR - Forward Looking Infra Red). The maximum dia. of Zinc Sulfide optics is up to 200 mm.

Spectral Transmittance (T) of CVD-ZnS FLIR grade Uncoated Polished Window thickness 5mm for range (2.5 - 25.0) microns.

Besides, the following spectral characteristics material is available too. Namely, Zinc Sulphide (CVD ZnS) ingots transparent in the spectral range (0.37 - 13.5) microns. Crystaltechno Ltd. manufactures from Zinc Sulphide (CVD-ZnS) the following optics: blanks, protective plates, windows, domes, wedges, lenses and meniscus. These products are used for infrared applications.

Spectral Transmittance (T) of CVD-ZnS Uncoated Polished Window thickness 5mm for range (200 - 1100) nm and for range (2.5 - 25) microns.

You can order the different ZnS (zinc sulphide) optics from CVD ZnS (zinc sulphide) material.
Maximum available size: ZnS blanks and ZnS windows - up to 200x500mm, thickness 15mm, ZnS domes - max dia. 300mm.
Crystaltechno Ltd. offers the manufacturing of ZnS optics (in detail please see Catalog):

Perhaps you will find required ZnSe optics at our stock, please see item Optical Crystals.


  ZnS Transmission Range   0.37 to 13.5 microns  
  Refractive Index   2.20084 at 10 microns  
  Reflection Loss   26.2% at 10 µm (2 surfaces)  
  dn/dT   +38.7 x 10-6/°C at 3.39µm  
  Index of Absorption   0.0006 cm-1 at 3.8 microns  
  Restrahlen Peak   30.5 microns  
  Density   4.09 g/cm3  
  Melting Point   1765 °C (dissociates about 700°C)° C  
  Thermal Conductivity   27.2 Wm-1K-1 at 298K  
  Thermal Expansion   6.5 x 10-6/°C at 273K  
  Hardness   Knoop 160 with 50g indenter  
  Specific Heat Capacity   515 J/(kg K)  
  Dielectric Constant   8  
  Young's Modulus (E)   74.5 GPa  
  Apparent Elastic Limit   68.9 MPa (10,000psi)  
  Poisson Ratio   0.28  
  Solubility   0.001 g/100g water  
  Molecular Weight   144.33  
  Class/Structure   HIP polycrystalline cubic, ZnS, F43m  


  Wavelength, µm 0.405 0.436 0.468 0.480 0.509 0.546 0.588 0.644 0.668 0.706  
  Refractive Index of ZnS 2.545 2.489 2.449 2.437 2.413 2.388 2.368 2.347 2.340 2.331  
  Wavelength, µm 0.780 0.795 0.852 0.894 1.014 1.129 1.530 2.058 3.000 3.500  
  Refractive Index of Zinc Sulfide 2.317 2.314 2.306 2.302 2.292 2.285 2.272 2.264 2.258 2.255  
  Wavelength, µm 4.000 4.500 5.000 8.000 9.000 10.00 11.25 12.00 13.00    
  Refractive Index 2.252 2.250 2.247 2.223 2.213 2.201 2.183 2.171 2.153    

Plano-Convex Lenses
Bi-Concave Lenses
Polished Domes

Ordering Info
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