Optical Window, Parallel, N-BK7, 50.8 mm, λ/20, 1000-1550nm

The 20BW40-30AR.18 Laser-Grade Parallel Window is parallel to less than 30 arc sec for minimal transmitted beam deviation. This 2 inch (50.8 mm) diameter N-BK7 window is 10 mm thick. It has Newport's AR.18 broadband IR antireflection coating for a 1000 to 1550 nm wavelength range. For demanding applications, such as intracavity laser applications, holography, and multiphoton imaging, this window has a λ/20 surface flatness and 10-5 scratch-dig significantly reducing unwanted scatter.
Specifications
- Diameter50.8 mm
- MaterialGrade A N-BK7
- Antireflection Coating1000-1550 nm
- Surface Flatnessλ/20 @ 632.8 nm
- Surface Quality10-5 scratch-dig
- Thickness10.0 mm
- Thickness Tolerance±0.25 mm
- Transmitted Beam Deviation±30 arc sec
- Wavefront Distortionλ/10 @ 632.8 nm
- Chamfers0.38–1.14 mm face width
- Chamfers Angle/Tolerance45° ±15°
- Cleaning
- Clear ApertureCentral 85% of diameter
- Diameter Tolerance+0/-0.15 mm
- Coating CodeAR.18
- Wedge≤30 arc sec
- Damage Threshold7.5 J/cm2, 10 ns pulses, 20 Hz at 1064 nm

Resources & Downloads
3D Product Models
2D Product Drawings
PARALLEL-S(95 kB, PDF)
Software
20BW40-30AR.18 Zemax File(5.5 kB, ZMX)
Other
20BW40-30AR.18 RoHS Certificate(706.5 kB, PDF) AR.18 Raw Data.xlsx(113.4 kB, XLSX)
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