Windows

Windows are most often used to separate two environments while allowing light to pass. Reflections from their surfaces can also be used to sample beams. Windows used in laser applications need to have low scatter, low absorption, low transmitted wavefront error, and high laser damage threshold. That’s why all of our catalog windows are manufactured to laser quality, with 10 – 5 scratch dig surface quality, λ/10 TWE, and optional high power antireflection coatings on one or two surfaces.

Our parallel windows have an ultra-low wedge to minimize angular deviation of the beam and minimize misalignment errors. In contrast, the interferometer flats have a 30 arc min wedge to minimize interference effects between surfaces, while large wedge windows have a 1° or 3° wedge to prevent interference from stray back reflections. With windows as thin as 1.0 mm and as large as 152.4 mm diameter, we have an instant solution for most applications.

In addition to off-the-shelf windows, we offer quick delivery on semi-custom fused silica windows in your choice of wedge, diameter, AR coating, and angle of incidence. Do the choices stop there? Absolutely not. Custom AR coatings can be deposited on our catalog windows or other substrate materials, as can any of our many dielectric and metal coatings. Whatever your needs may be, we have the expertise and high volume capacity available to create and deliver the ideal solution for you.

Capabilities

Standard Custom Options
Types
  • Parallel, low wedge, large wedge
  • Round, square, rectangular
  • 0° or 45° AOI
Materials N-BK7, UV-grade fused silica MgF2, CaF2, Suprasil 1, crystal quartz, optical crown glass, Infrasil 301, N-BAK1, N-SF10, N-SF2, N-SF11, sapphire
Dimensions 10.0 to 152.4 mm 3 to 300 mm
Wedge Parallel: < 10 arc sec Low wedge: ≤ 5 arc min Large wedge: 30 ± 5 arc min Other wedge angles
Coatings
  • Narrowband V-coat AR
  • Dual wavelength AR (1064/532)
  • Broadband Multilayer AR
  • Other metal and dielectric coatings
  • Other AR wavelengths (193 - 2100 nm)
  • Other angles of incidence
  • Ultra-low loss AR
  • High damage threshold
Quality Laser quality See manufacturing tolerances below

Windows Manufacturing Capabilities**

Surface Tolerances Precision Laser Quality High Precision
Surface Quality
(scratch - dig)
40 - 20 10 - 5 5 - 2
Surface roughness (Å, RMS) 20
5
1
Transmitted wavefront error
(P-V @ 633 nm before coating)
λ/2 λ/10 λ/20
Dimensional Tolerances Standard Precision High Precision
Diameter (mm) +0.000 / -0.250 +0.000 / -0.025 +0.000 / -0.005
Length & width (mm) ± 0.050 +0.000 / -0.025 +0.000 / -0.010
Thickness (mm) ± 0.250 ± 0.050 ± 0.005
Parallelism ≤ 5 arc min ≤ 1 arc sec ≤ 0.5 arc sec
Clear Aperture ≥ 85% ≥ 90% 100%

** Note: The general tolerance specifications above are intended to guide determination of appropriate tolerances based both on relative cost and manufacturability. Part-specific tolerances will vary depending on size, material, shape and aspect ratio. Tighter tolerances may be possible, so please contact us to discuss your custom specifications. All specifications do not need to be from a single column, though trade-offs may be required in order to meet the desired combination of cost and performance.