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Barium fluoride optical lenses and windows

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

Explore Related Optical Materials

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

Company Registered in England Registered Office: 

Global Optics (UK) Ltd, Unit 6 Branksome Business Park, Bourne Valley Road, Poole, Dorset, BH12 1DW. Tel: 01202 767476
Company No. 3509979
© Global Optics UK Ltd - Precision Optics Supplier - UV, Visible And Infrared Optical Materials And Components For Scientific Optical Applications 

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