• T ≥ 94% for λ = 200 nm to 6 µm
• >50% Transmission at 120 nm
• Ø1"
• MgF₂ Substrate

This Thorlabs’ Magnesium Fluoride window offers excellent transmission from deep in the ultraviolet region to the mid-infrared. MgF₂ widows are extremely durable and introduce minimal abrasions. Thorlabs MgF₂ windows are cut with the optical axis parallel to the c-axis of the crystal to minimize birefringence.

MgF₂ windows are well suited for deep-UV applications, even extending into the vacuum-UV region. They offer >50% transmission at 120 nm, making them suitable for use with excimer laser systems, as well as applications involving the Hydrogen Lyman-o line at 121 nm. Thorlabs’ MgF₂ windows are also useable in the UVA, UVB, visible and IR ranges, with approximately 94% transmission from 200-1000 nm, and approximately 95% transmission from 1-6 µm.

• Thickness: 5 mm
• Thickness Tolerance: ±0.3 mm
• Axis Orientation: ±0.5°
• Diameter Tolerance: +0.0/-0.2 mm
• Surface Quality: 20-10 Scratch-Dig
• Parallelism: ≤5 arcmin
• Surface Flatness (@633 nm): λ/8 Over Clear Aperture
• Clear Aperture: >90% Diameter