Zinc Sulphur( ZnS) mateiral have two grades and can be use in imaging systems. Regular grade material is grown by the chemical vapor deposition process. This material is often used in the 3um to 5 um and 8um to 12 um region. It has reasonable hardness and is moderately priced. It is available in large size as well. It can replace ZnSe in certain harsh environment. Multi Spectral grade ZnS is treated after growth to eliminate microscopic voids and defects which occur in the regular grade, thus extending the usefulness of this material to include the visible region.

Transmission Range: 3~5um and 8-12um

Thermal Expansion Coefficient: 7.85 x10^-6/K

Density: 4.09 g/cm³

Specifications:
Material: Zinc Sulphur 
Diameter Tolerance: +0.0, -0.1mm
Thickness Tolerance: ±0.2mm 
Clear Aperture: >80% 
Parallelism: 1 arc minute 
Flatness:λ/2 @ 632.8 nm 
Surface quality: 60/40 scratch and dig 
Protective Bevel: <0.25x45deg
Coating: Uncoated

Custom designs for other sizes and coatings are also available upon request.