Sapphire (Al2O3)
Mechanically robust crystal with wide optical transmission
Ultra-Hard Optical Crystal
Sapphire is an extremely hard, durable single-crystal material offering wide optical transmission, high thermal conductivity, and excellent resistance to abrasion and chemical attack. It is commonly used for high-pressure windows, harsh-environment optics, and protective optical components in aerospace, defence, and industrial systems. Sapphire is chosen when mechanical durability is as important as optical performance.
Is this material right for your application?
Use When:
Avoid When:
Consider Alternatives:
Extreme mechanical durability is required
Scratch, abrasion, or pressure resistance is critical
Optics are exposed to harsh or outdoor environments
High temperatures are expected
Protective windows are needed without optical distortion
Tight budgets limit material choice
Complex geometries require extensive machining
Low refractive index is critical
Weight reduction is a priority
Fused Silica – better optical precision and lower cost
Magnesium Fluoride (MgF₂) – UV optics with less machining complexity
Zinc Sulphide (ZnS) – IR windows with lower material cost
Key Properties
Optical
Broad transmission from UV to IR
High refractive index
Mechanical
Extremely high hardness
Exceptional scratch and abrasion resistance
Thermal / Environmental
High thermal conductivity
Excellent chemical resistance
Explore Related Optical Materials
Frequently asked questions about Barium Fluoride specifications and use-cases
FAQ
Q1. What wavelength range is Sapphire suitable for?
Sapphire transmits from ~150 nm to ~5.5 µm.
Q2. Is Sapphire mechanically strong?
Yes. Sapphire is extremely hard and abrasion-resistant.
Q3. Is Sapphire suitable for harsh environments?
Yes. It performs well in high-pressure, high-temperature, and abrasive conditions.
Q4. What are alternatives to Sapphire?
Fused Silica and CaF₂ depending on optical requirements.
High cost compared to glass materials.
Difficult to machine due to hardness.
Excellent chemical resistance.