Photonic Materials Technology Section (PMTS)

Optical and Glass-Ceramic Laboratory

Monolithic growth of free-standing ZnS blanks and domes are fabricated using sub-atmospheric pressure chemical vapour deposition (CVD) (Figure 8). Optical properties are consistent with the earlier reports. Yellow coloration in the ceramics is due to trapping of sulfur. This material is used as IR-window to protect thermal imaging equipment for strategic application.

1. Blank, Diameter= 80 mm; Thickness = 2.0 mm
2. Dome, Rim Diameter = 80 mm, Thickness = 2.0 mm

1. Phase: Cubic crystal symmetry with lattice parameters 5.405Ǻ
2. Transparency: 65–68 % transmission in the 8–12 m wavelength region.
3. Vicker’s Hardness: 175 – 200 (with 50 gm applied load)
4. Density: 4.09 gm/cc

Free-standing transparent ZnS blanks and dome

XRD and UV-Vis-IR transmission of the ZnS samples