Sapphire dome
Sapphire is a single crystal material that has excellent light transmission properties and can work in the visible and infrared light ranges. It has high hardness, high corrosion resistance, high heat resistance and good mechanical strength. It has a good transmittance in the visible range, usually more than 80%. In the infrared range, especially in the near infrared and mid-infrared bands, its transmittance is very high, which can reach more than 90%.
Sapphire Domes are an ideal way to shield other optical components without sacrificing the field of view of the optics inside.Sapphire domes can provide a very strong and durable protective environment to house other optical components and it’s ideal for visible and near IR optics applications.Sapphire domes are much stronger than glass domes at similar thicknesses while being much more scratch resistant.
Our Company can provide sapphire dome different types of domes including hemispheric and hyper-hemispheric domes, domes with a kerf and domes in a spherical crown shape,uncoated or upon request.
Technical parameters of Sapphire dome
Material | Sapphire |
Diameter range | 5mm-300mm |
Diameter tolerance | +/-0.03mm |
Surface accuracy | 1/4-1 lambda |
Surface quality | 40/20, 60/40, 80/50 |
Clear Aperature | 90% |
Coating | Uncoated or customized |
Material properties of sapphire
Optical Properties | |
Transmission Range | 0.2-5μm |
Ne Refractive index@Ne | 1.7771 |
Structure | trigonal system |
Physical Properties | |
Density[g/cm3] | 3.98 |
Melting Point [deg C] | 2030 |
Thermal Conductivity[W/(m×deg C)] | 25.2 |
Thermal Expansion[deg C-1 ] | 5.66*10-6 |
Specific Heat Capacity[J/(kg×deg C)] | 0.7610*103 |
Young's Modulus[GPa] | 34-37 |
Volume elasticity coefficient[GPa] | 250 |
Poisson Coefficient | 0.309 |
Chemical Properties | |
Molecular Weight/ g/mol | 101.96 |
Solubility | 98*10-6 |
Transmission curve
Sapphire (Al2O3)- with a large transmission range of 150nm-4.5µm sapphire is a good generalist but where sapphire truly shines is its material robustness. You can use sapphire in almost any harsh environment and it will take the punishment. From extreme resistance to thermal conductivity, a high dielectric constant and chemical resistance, sapphire will take almost anything thrown at it and ask for seconds. Only behind diamond in terms of material hardness but unlike diamond can be made extremely thin, which further improves transmission.
