Magnesium Fluoride (MgF2 crystals)has the following exceptional properties that make it a very important optics crystal.

High optical transmittance from the vacuum ultraviolet to the infrared spectrum region(0.12μm«8.5μm).
Resistant to mechanical and thermal shock, to radiation.
Chemically stable.
Used for Optical prisms, lenses, wedges, windows, other optical components,and etc.
A positive birefringent crystal ,used for optical fiber communication.

MgF2 crystals: High transmittance

5% @ 120nm, 78% @ 140nm, 90% @ 200nm,93% @ 300-5000nm

We can produce UV Blank, UV Windows, UV Lenses, UV Cylindrical Lenses, UV Prisms, UV Wedges and etc. according to custmers' requirments and drawings. Specification of our standard products are showed as following.

UV Blank

For customers who need large size and single MgF2 crystal ingot to produce elements.

UV Windows

UV Windows are our most favor in this production line. We can provide single crystal mosaic free DUV grade MgF2 material and it can reach transmission greater than 65% at 121.6nm, of course this grade material can be used for excimer & Nd:YAG laser optics. The quality of a DUV window can be extremely critical, it should be of high purity and polish in order not to affect the optical system.

Parameter Commercial grade Precision grade Ultra-precision grade
Substrate Material DUV grade MgF2
Orientation Perpendicular to C-axis
Diameter Tolerance +0/-0.10mm
Thickness Tolerance +/- 0.10mm
Clear Aperture >Central 90% of diameter
Surface Quality 60-40 S/D 40-20 S/D 20-10 S/D
Parallelism <3~5 arc min <1 arc min
Surface Flatness 1λ per 25mm λ/4 λ/10
Chamfer 0.15~0.35mm x 45°
Size (¦ÕxT mm) 12.7 x 2; 20.0 x 3; 25.4 x4; 38.1 x 5; 50.8 x 5; 50.8 x 6.35

UV Lenses

We provide Singlet Lenses and Doublets Lenses with the material of DUV grade MgF2 crystal, BCT's engineers can design special focusing systems upon requirement.

Parameter Commercial grade Precision grade Ultra-precision grade
Substrate Material DUV grade MgF2
Focal Length Tolerance +/- 0.5%
Diameter Tolerance up to +0/-0.02mm
Thickness Tolerance up to +/- 0.02mm
Clear Aperture >Central 95% of diameter
Surface Quality 60-40 S/D 40-20 S/D 20-10 S/D
Centration <0.05mm <0.01mm
Surface Flatness 1λ per 25mm λ/4 λ/10
Chamfer 0.15~0.35mm x 45°
Coating Coating are available upon request

UV Cylindrical Lenses

Our cylindrical lenses are either plano-convex (positive) or plano-concave (negative).

Parameter Commercial grade
Substrate Material DUV grade MgF2
Focal Length Tolerance +/- 2%
Diameter Tolerance up to +0/-0.10mm
Thickness Tolerance up to +/- 0.20mm
Clear Aperture >Central 85% of diameter
Surface Quality 60-40 S/D
Centration <3 arc minutes
Chamfer 0.15~0.35mm x 45°
Coating Coating are available upon request

UV Prisms

We can manufacture many types of prism, each having a particular geometry to achieve the reflections necessary to perform a specific imaging task.

Parameter Commercial grade Precision grade Ultra-precision grade
Substrate Material DUV grade MgF2
Diameter Tolerance +1.0/-0.10mm
Clear Aperture >Central 90% of diameter
Surface Quality 60-40 S/D 40-20 S/D 20-10 S/D
Centration 1 arc min 30 arc seconds 5 arc seconds
Surface Flatness 1λ per 25mm λ/4 λ/10
Chamfer 0.15~0.35mm x 45°
Coating Coating are available upon request