- Transmits wavelength range 1.2-7 μm
- Ideal for weight sensitive applications
- Cheaper than germanium and ZnSe
Silicon (Si) Windows manufactured from optical grade silicon are popular for the 1.2 – 7μm spectral region due to their low cost and low density. Due to its low density (half that of germanium or zinc selenide), silicon is ideal for weight sensitive applications, especially those in the MWIR thermal imaging 3 – 5μm region. Density is 2.329 g/cm3 and Knoop Hardness is 1150, making it harder and less brittle than germanium.
| Specifications | |
| Materials | Silicon crystals |
| Diameter Range | ~ 300mm |
| Aperture | >90% |
| Dimension Tolerance | +0.0/-0.2mm |
| Thickness Tolerance | +/-0.2mm |
| Surface Quality | 80/50 S/D |
| Parallelism | 1 arc minute |
| Chamfer | 0.3-0.5mmx45degree |
| Coating | AR/AR or DLC/AR |