ZnS is a very important optical crystals applied in IR waveband.
Transmitting range of CVD ZnS is 8um-14um, high transmittance, low absorption, ZnS with multi-spectrum level by heating etc. static pressure technics has improved the transmittance of IR and visible range.
Zinc Sulphide is produced by synthesis from Zinc vapour and H2S gas, forming as sheets on Graphite susceptors. Zinc Sulphide is microcrystalline in structure, the grain size being controlled to produce maximum strength. Multispectral grade is then Hot Isostatically Pressed (HIP) to improve the mid IR transmission and produce the visibly clear form. Single crystal ZnS is available, but is not common.
Zinc Sulphide oxidizes significantly at 300°C, exhibits plastic deformation at about 500°C and dissociates about 700°C. For safety, Zinc Sulphide windows should not be used above 250°C in normal atmosphere.
Applications：Optics,electronics, photoelectronic devices.
Excellent optical uniformity,
resisting acid-base erosion,
stable chemical performance.
High refractive index,
high refractive index and high transmittance within visible range.
|Transmission Range :||0.37 to 13.5 μm|
|Refractive Index :||2.20084 at 10 μm (1)|
|Reflection Loss :||24.7% at 10 μm (2 surfaces)|
|Absorption Coefficient :||0.0006 cm-1 at 3.8 μm|
|Reststrahlen Peak :||30.5 μm|
|dn/dT :||+38.7 x 10-6 /°C at 3.39 μm|
|Density :||4.09 g/cc|
|Melting Point :||1827°C (See notes below)|
|Thermal Conductivity :||27.2 W m-1 K-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-1 K-1|
|Dielectric Constant :||88|
|Youngs Modulus (E) :||74.5 GPa|
|Shear Modulus (G) :||n/a|
|Bulk Modulus (K) :||n/a|
|Elastic Coefficients :||Not Avalailable|
|Apparent Elastic Limit :||68.9 MPa (10,000 psi)|
|Poisson Ratio :||0.28|
|Solubility :||65 x 10-6 g/100g water|
|Molecular Weight :||97.43|
|Class/Structure :||HIP polycrystalline cubic, ZnS, F42m|