
Magnesium Fluoride (MgF2)
Hard crystal with excellent UV transmission and durability
UV Optical Crystal
Magnesium Fluoride is a durable optical crystal with excellent ultraviolet transmission and good environmental stability. It is widely used for UV windows, lenses, and as a substrate material for anti-reflection coatings. MgF₂ offers improved hardness compared to many fluoride crystals, making it suitable for applications where both UV performance and durability are required.
Is this material right for your application?
Use When:
Avoid When:
Consider Alternatives:
UV transmission is required with improved durability
A hard fluoride crystal is preferred
Anti-reflection coating substrates are needed
Optical components are exposed to moderate environmental stress
UV windows or lenses are used
Broad mid-IR or LWIR transmission is required
Very high refractive index is needed
Severe mechanical shock is expected
Calcium Fluoride (CaF₂) – broader UV–IR transmission
Lithium Fluoride (LiF) – deeper UV transmission
Fused Silica – higher thermal stability
Key Properties
Optical
Excellent ultraviolet transmission
Low refractive index
Mechanical
Harder than most fluoride crystals
Good surface durability
Environmental
Improved moisture resistance compared to other fluorides
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Frequently asked questions about Barium Fluoride specifications and use-cases
FAQ
Q1. What wavelength range does MgF₂ support?
MgF₂ transmits from ~120 nm to ~7 µm.
Q2. Is MgF₂ commonly used as a coating material?
Yes. MgF₂ is widely used for anti-reflection coatings.
Q3. Is MgF₂ durable?
Yes. It is more durable than many fluoride crystals.
Q4. What are common alternatives to MgF₂?
CaF₂ and LiF.
Low refractive index
Good environmental stability
Common in UV windows and coated optics