Magnesium Fluoride Windows


  • >50% Transmission at 120 nm
  • Transmission ≥94% for λ = 200 nm - 6 µm
  • Extremely Durable Ø1/2" and Ø1" Windows Available
  • Suitable for Excimer Lasers and Other Deep UV Applications

WG61050

Ø1"

WG60530

Ø1/2"

Related Items


Please Wait
Flat Window Selection Guide
Wavelength Range Substrate Material
180 nm - 8.0 μm Calcium Fluoride (CaF2)
185 nm - 2.1 μm UV Fused Silica
200 nm - 5.0 μm Sapphire
200 nm - 6.0 μm Magnesium Fluoride (MgF2)
220 nm to >50 µm CVD Diamond Windows
230 nm - 1.1 µm UV Fused Silica, Textured Antireflective Surface
250 nm - 1.6 µm UV Fused Silica, for 45° AOI
250 nm - 26 µm Potassium Bromide (KBr)
300 nm - 3 µm Infrasil®
350 nm - 2.0 μm N-BK7
600 nm - 16 µm Zinc Selenide (ZnSe)
1 - 1.7 µm Infrasil®, Textured Antireflective Surface
1.2 - 8.0 μm Silicon (Si)
1.9 - 16 μm Germanium (Ge)
2 - 5 μm Barium Fluoride (BaF2)
V-Coated Laser Windows

Features

  • T ≥ 94% for λ = 200 nm to 6 μm
  • >50% Transmission at 120 nm
  • Ø1/2" and Ø1" Versions Available

Thorlabs' Magnesium Fluoride windows are available in Ø1/2" and Ø1" sizes. They offer excellent transmission from deep in the ultraviolet region to the mid-infrared. MgF2 windows are extremely durable and introduce minimal aberrations. 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-α line at 121 nm. Thorlabs' MgF2 windows are also usable in the UVA, UVB, visible and IR ranges, with approximately 94% transmission from 200 - 1000 nm, and approximately 95% transmission from 1 - 6 µm.

Optical Coating and Subtrates
Optic Cleaning Tutorial

Posted Comments:
user  (posted 2024-08-29 10:44:48.903)
Hi, Looking at this product from profile, there seems to be two phases or material finishes. It is supposed to be bulk uncoated material, so what is this ? And is there a recommended side for incident light ? Thanks, Arnaud
cdolbashian  (posted 2024-08-30 12:53:06.0)
Thank you for reaching out to us with this inquiry Arnaud. These are cut and polished bulk material which are uncoated. I have contacted you do discuss any potential misunderstanding stemming from the presentation of these windows on our web page.
Alexander Enders  (posted 2023-07-19 10:22:08.217)
Hello, I have a quick question: What is the orientation of the optical axis of your MgF2 windows? Perpendicular to the plane of the window to prevent birefringence? Best Alex
jdelia  (posted 2023-07-19 01:59:53.0)
Thank you for contacting Thorlabs. Thorlabs' MgF2 windows are cut with the optical axis parallel to the c-axis of the crystal to minimize birefringence.
user  (posted 2021-07-16 04:31:57.333)
Hi i like a WG61050 - Ø1" MgF2 Broadband Precision Window, coated to 1064 HR also with PL//R =100mm CC thanks
YLohia  (posted 2021-08-27 02:46:42.0)
Hello, custom optics can be requested by emailing techsales@thorlabs.com. We will discuss the possibility of offering this directly.
Enrique Vasco  (posted 2020-10-03 15:11:52.777)
Please, could you provide me with data on MgF2 window damage thresholds for 10 ns-pulsed UV laser, as the product description specifies that it is suitable for excimer laser and deep UV applications? Thankx
YLohia  (posted 2020-10-07 02:30:18.0)
Thank you for contacting Thorlabs. Unfortunately, we don't test or specify LIDT for bulk optics. Based on your beam parameters (266 nm, 100 mJ, 8 ns, 10 Hz, 3mm) and the literature available online, we expect the WG60530 to not sustain damage, but we cannot provide any guarantees for this at the moment.
Window Selection Guide (Table Sorted by Wavelength)
Substrate and Window Type Wavelength Range Available AR Coatings Reflectance over AR Coating Rangea Transmission Data Reflectance Data
Calcium Fluoride (CaF2):
Flat or Wedged		 180 nm - 8.0 μm Uncoated -
Raw Data		 -
-D Coating, 1.65 - 3.0 µm Ravg < 1.0%; Rabs < 2.0% at 0° AOI
Raw Data
Raw Data
UV Fused Silica:
Flat, Wedged, V-Coated Flat,
or V-Coated Wedged		 185 nm - 2.1 μm Uncoated
(Flat or Wedged)		 -
Raw Data		 -
-UV Coating,
245 - 400 nm
(Flat or Wedged)		 Ravg < 0.5% at 0° AOI -
Raw Data
-C3 Coating,
261 - 266 nm
(V-Coated)		 Ravg < 0.5% at 0° AOI - Click to View Index Plot
Raw Data
-C6 Coating,
350 - 450 nm
(V-Coated)		 Ravg < 0.5% at 0° AOI - Click to View Index Plot
Raw Data
-A Coating,
350 - 700 nm
(Flat or Wedged)		 Ravg < 0.5% at 0° AOI -
Raw Data
-B Coating,
650 - 1050 nm
(Flat or Wedged)		 Ravg < 0.5% at 0° AOI -
Raw Data
-C Coating,
1050 - 1700 nm
(Flat or Wedged)		 Ravg < 0.5% at 0° AOI -
Raw Data
Sapphire:
Flat or Wedged		 200 nm - 5.0 μm Uncoated -
Raw Data		 -
-D Coating, 1.65 - 3.0 µm Ravg < 1.0% at 0° AOI
Raw Data
Raw Data
-E1 Coating, 2.0 - 5.0 µm Ravg < 1.50%, Rabs < 3.0%
(per Surface, 2.0 - 5.0 µm);
Ravg < 1.75%
(per Surface, 2.0 - 4.0 µm) at 0° AOI
Raw Data
Raw Data
Magnesium Fluoride (MgF2):
Flat or Wedged		 200 nm - 6.0 μm Uncoated -
Raw Data		 -
Barium Fluoride (BaF2):
Flat or Wedged 		200 nm - 11 µm Uncoated
(Wedged Only)		 -
Raw Data		 -
-E1 Coating, 2 - 5 µm Ravg < 1.25%; Rabs < 2.5% at 0° AOI
Raw Data		 Icon
Raw Data
UV Fused Silica, for 45° AOI:
Flat or Wedged		 250 nm - 1.6 µm Coating for
250 nm - 450 nm		 Ravg < 1.0% at 45° AOI info
Raw Data
Coating for
350 nm - 1100 nm		 Ravg < 2.0% at 45° AOI info
Raw Data
Coating for
400 nm - 700 nm		 Ravg < 1.0% at 45° AOI info
Raw Data
Coating for
600 nm - 1700 nm		 Ravg < 1.5% at 45° AOI info
Raw Data
Coating for
700 nm - 1100 nm		 Ravg < 1.0% at 45° AOI info
Raw Data
Coating for
1200 nm - 1600 nm		 Ravg < 1.0% at 45° AOI info
Raw Data
Potassium Bromide (KBr):
Flat		 250 nm - 26 µm Uncoated - -
Infrasil®:
Flat		 300 nm - 3 µm Uncoated -
Raw Data		 -
N-BK7:
Flat, Wedged, V-Coated Flat,
or V-Coated Wedged		 350 nm - 2.0 μm Uncoated
(Flat or Wedged)		 -
Raw Data		 -
-A Coating,
350 - 700 nm
(Flat or Wedged)		 Ravg < 0.5% at 0° AOI -
Raw Data
-C7 Coating,
400 - 700 nm
(V-Coated)		 Ravg < 0.5% at 0° AOI - Click to View Index Plot
Raw Data
-C10 Coating,
523 - 532 nm
(V-Coated)		 Ravg < 0.5% at 0° AOI - Click to View Index Plot
Raw Data
-C11 Coating,
610 - 860 nm
(V-Coated)		 Ravg < 0.5% at 0° AOI - Click to View Index Plot
Raw Data
-B Coating,
650 - 1050 nm
(Flat or Wedged)		 Ravg < 0.5% at 0° AOI -
Raw Data
-C13 Coating,
700 - 1100 nm
(V-Coated)		 Ravg < 0.5% at 0° AOI - Click to View Index Plot
Raw Data
C14 Coating,
1047 - 1064 nm
(V-Coated)		 Ravg < 0.5% at 0° AOI - Click to View Index Plot
Raw Data
-C15 Coating,
523 - 532 nm &
1047 - 1064 nm
(V-Coated)		 Ravg < 0.5% at 0° AOI - Click to View Index Plot
Raw Data
-C Coating,
1050 - 1700 nm
(Flat or Wedged)		 Ravg < 0.5% at 0° AOI -
Raw Data
Zinc Selenide (ZnSe):
Flat or Wedged		 600 nm - 16 µm Uncoated -
Raw Data		 -
-D Coating, 1.65 - 3.0 µm Ravg < 1.0%; Rabs < 2.0% at 0° AOI
Raw Data
Raw Data
-E4 Coating, 2 - 13 µm
(Only Flat)		 Ravg < 3.5%; Rabs < 6% at 0° AOI
Raw Data
Raw Data
-E2 Coating, 4.5 - 7.5 µm
(Only Flat)		 Ravg < 1.0%; Rabs < 2.0% at 0° AOI
Raw Data
Raw Data
-E3 Coating, 7 - 12 µm
(Only Wedged)		 Ravg < 1.0%; Rabs < 2.0% at 0° AOI
Raw Data		 Icon
Raw Data
-G Coating, 7 - 12 µm
(Only Flat)		 Ravg < 1% at 0° AOI
Raw Data
Raw Data
Silicon (Si):
Flat or Wedged		 1.2 - 8.0 μm Uncoated -
Raw Data		 -
-E1 Coating, 2 - 5 µm
(Only Wedged)		 Ravg < 1.25%; Rabs < 2.5% at 0° AOI
Raw Data		 Icon
Raw Data
-E Coating, 3 - 5 µm
(Only Flat)		 Ravg < 2% at 0° AOI
Raw Data
Raw Data
Germanium (Ge):
Flat or Wedged		 1.9 - 16 μm Uncoated, 2.0 - 16 μm -
Raw Data		 -
-C9 Coating, 1.9 - 6 µm
(Only Flat)		 Ravg < 2% at 0° AOI
Raw Data
Raw Data
-E3 Coating, 7 - 12 µm Ravg < 1.0%; Rabs < 2.0% at 0° AOI
Raw Data		 Icon
Raw Data
  • Reflectance is given per surface and each window is coated on both sides.
Back to Top

Magnesium Fluoride (MgF2) Windows, Uncoated

Item #WG60530WG61050
Diameter  1/2" (12.7 mm) 1" (25.4 mm)
Diameter Tolerance +0.0 / -0.2 mm
Thickness 3.0 mm 5.0 mm
Thickness Tolerance ±0.3 mm
Clear Aperture >90% Diameter
Axis Orientation ±0.5°
Parallelism ≤5 arcmin
Surface Flatnessa λ/8 over Clear Aperture
Surface Quality 20-10 Scratch-Dig
Wavelength Range 200 nm - 6.0 μm (Uncoated)
Substrate Magnesium Fluorideb
Transmission Data
Raw Data
  • Measured at 633 nm
  • Click Link for Detailed Specifications on the Substrate
Based on your currency / country selection, your order will ship from Newton, New Jersey  
+1 Qty Docs Part Number - Universal Price Available
WG60530 Support Documentation
WG60530Ø1/2" MgF2 Broadband Precision Window, Uncoated
$181.75
3-5 Days
WG61050 Support Documentation
WG61050Ø1" MgF2 Broadband Precision Window, Uncoated
$273.23
3-5 Days
Additional Flat Windows
  • UV Fused Silica Windows, 0.185 - 2.1 µm

  • UV Fused Silica Textured Antireflective Windows

  • N-BK7 Windows, 0.35 - 2 µm

  • V-Coated Laser Windows

  • Calcium Fluoride Windows,
    0.18 - 8 µm

  • Sapphire Windows, 0.2 - 5.0 µm

  • Magnesium Fluoride Windows, 0.2 - 6 µm

  • Polycrystalline CVD Diamond Windows

  • Potassium Bromide Windows, 0.25 - 26 µm

  • Infrasil® Windows, 0.3 - 3 µm

  • Infrasil® Textured Antireflective Windows

  • Zinc Selenide Windows,
    0.6 - 16 µm

  • Silicon Windows, 1.2 - 8.0 µm

  • Germanium Windows,
    1.9 - 16 µm

  • Barium Fluoride Windows,
    2 - 5 µm

  • UV Fused Silica
    Brewster Windows

  • High Vacuum ConFlats and Windows

  • Wedged Windows