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Optical B270 K9 Windows
Coligh manufactures high-quality optical windows made from normal optical glass K9, B270, N-BK7 substrates, ensuring excellent light transmission for industrial applications.
- A variety of substrates are available K9 B270 N-BK7
- Uncoated versions are available
- Coated windows are available, standard thin film coatings are VIS, NIR, SWIR
- High surface quality, 10/20 finish is available
- Any shape, size <1000mm
Optical B270 N-BK7 K9 Windows Description
Coligh manufactures K9, B270, and N-BK7 optical protective windows, which are flat windows specifically designed to protect sensors. We offer large-size, high-precision, and high-surface-quality uncoated optical substrates and coated optical windows.
The properties of uncoated optical substrates: Ravg < 0.5% @ 350-2000nm
Optical specifications for broadband anti-reflective (AR) coatings:
- VIS broadband AR coating: 350-700nm @ Ravg < 0.5%
- NIR broadband AR coating: 600-1100nm @ Ravg < 0.5%
- SWIR broadband AR coating: 900-1700nm @ Ravg < 0.5%
Standard sizes range from Dia 5mm to Dia 50.8mm.
We also accept custom orders with sizes up to <1000mm and surface quality up to 10/20. In addition to K9, N-BK7, and B270, we offer optical windows in a variety of materials and shapes, including UV-fused silica, sapphire, barium fluoride, zinc sulfide, zinc selenide, silicon, and cat’s eye windows.
Optical B270 N-BK7 K9 Windows Detail Display
Optical B270 N-BK7 K9 Windows Technical Datasheet
| Standard UV Fused Silica windows | |
| Substrate | B270 N-BK7 K9 |
| Diameter allowance | +0.0/-0.1mm |
| Thickness allowance | +/-0.2mm |
| Standard size | Dua5.0mm -Dia50.8mm |
| Parallelism error | <30 arcseconds |
| PV | 1/4λ 632.8nm |
| Surface quality | 60/40 |
| Custom Option | Size<1000mm |
| Surface quality 20/10 | |
| Parallelism error 0.25” | |
| RMS Full aperture 13/60nm | |
| Materil:UV-fused silica, sapphire, barium fluoride, zinc sulfide, zinc selenide, silicon, and cat’s eye windows | |
Optical B270 N-BK7 K9 Windows Applications
B270, N-BK7 and K9 are three common optical glass materials, which are widely used in optical windows in many industries. For example:
- N-BK7 and K9 are often used in precision optical lenses, prisms and windows due to their high light transmittance (visible light to near infrared) and low birefringence. K9 and B270 are used to protect sensors of microscopes, telescopes, camera lenses or non-critical optical paths
- N-BK7, K9 and B270 are also used as output windows and laser protection windows in low-power laser systems
- In industrial inspection and automation, these windows are also used for high-precision industrial camera protection windows to prevent corrosion on the painting and environmental resistance
- In aerospace and defense, the near-infrared band of N-BK7 is also used in sensor protection covers for spacecraft
- In automotive and lidar, K9 and N-BK7 are also used for lidar protection windows for self-driving cars
