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AR Coated BK7 Windows

BK7 window is the most common type of window. It has good performance over visible and near infrared wavelength region. At the same time,BK7 window is ideal for applications require minimal transmitted beam deviation. It is suitable for AR coating .
  • product origin:

  • shipping port:

    Fuzhou China
  • lead time:

    4 working weeks
  • payment:

    T/T Payment, Western Union
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  • description

1. What is BK7 window?

N-BK7 Windows are a Schott borosilicate material used in optical applications from the visible to the NIR. BK7 window has good performance over visible and near IR spectrum for most application.

2. What’s theadvantage of bk7 window?

· Clear, uniform color

· Nearly free of bubbles and inclusions

· A high degree of purity and homogeneity

· Excellent chemical and stain resistance

· Superior transmission in the VIS to NIR spectrum

· Low absorption and uniform transmission in the visible spectrum


3. Is the BK7 window can used inthermal shock application?


No,it is a very temperature sensitive material and therefore not suitable for applications where it will be exposed to thermal shock. 


4. UNI Optics carries a wide range of N-BK7 Windows in-house and has the ability to:


· Fabricate custom shapes and sizes

· Achieve parallelism of < 2 arc seconds

· Drill holes, notch glass and provide custom bevels

· Polish glass down to 3mm in diameter and 0.5mm thick

· Modify and resurface customer supplied materials

· Precision polish optics with non-standard aspect ratios

· Provide broadband AR coating for the visible spectrum as well as custom coatingsSpecifications:


  Standard High Precision
Dimension Tolerance +0.0/-0.2 +0.0/-0.02
Thickness Tolerance ±0.2 ±0.005
Surface quality: 60-40 10-5
Clear Aperture >85% >95%
Flatness(per 25mm@633nm) λ /2 λ /10
Parallelism 3 min 3 sec

Note for N-BK7 Window:

(1). Custom-made N-BK7 windows at any size from Φ2.0mm to Φ350mm clear aperture are available.
Besides round, N-Bk7windows at shape of quadrate, triangular, or other polygonal are available.
(2). Thickness from 1.0mm to 50.0 mm is available upon request.
(3). 100% clear aperture is available upon request.
(4). Better bevel is available upon request.
(5). N-BK7 Windows with Anti-Reflective(AR), High-Reflective(HR), Partial-Reflective(PR) coating are available.

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1) UV Enhanced Aluminum : Ravg > 85% from 250nm to 400nm

2) Protected Aluminum: Ravg > 87% from 400nm to 800nm

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