Properties of Optical Sapphire Window:
Optical Windows are used as viewports to protect other components within an optical assembly, instrument, or laser. In certain applications, optical windows are required to withstand harsh environmental conditions and provide high levels of performance and reliability. Sapphire window has several unique properties that make it the ideal material for these applications.
1. Synthetic Sapphire, the single crystal form of Al2O3, is one of the hardest materials ( 9 Mohs hardness). Because of its structural strength, the sapphire window can be made much thinner than other common optical windows, with better transmittance performance.
2. High thermal stability and excellent thermal conductivity make the sapphire window suitable for the applications in high power. The loss in a sapphire window is less than in another common optical window.
3. Sapphire windows can withstand considerably higher temperatures than most optical windows with zero degradation.
4. Sapphire Windows will not get dark and lose their brilliancy when exposed to UV light.
5. Sapphire windows are extremely stable and resistant to attack by strong acid due to sapphire’s high dielectric constant.
6. Sapphire windows offer wideband transmission from UV to Mid-IR (0.15-5.5µm).
All these unique properties make sapphire windows the ideal material for extreme mechanical, chemical & optical applications.
Sapphire Optical window Specifications:
| Name | Sapphire Optical window |
| Material | Sapphire single crystal |
| Orientation | C-axis |
| Hardness | Mohs 9 |
| Length | 1-500 mm |
| Length Tolerance | ±0.05 mm |
| Thickness | 0.1-100mm |
| Thickness tolerance | ±0.05mm |
| Parallelism | ≤3 ARC Min |
| Surface quality | DSP 40/20 |