TECHSPEC® λ/4 N-BK7 Precision Windows are ideally suited for industrial and low-power laser applications. The high tolerance design yields minimal beam distortion and scatter. Broadband coating options extend the range of these precision windows through the visible and near-infrared spectra. TECHSPEC® λ/4 N-BK7 Precision Windows are offered in circular and rectangular sizes ranging from 2mm to 200mm.
Note: New additions to this product family may be specified with a transmitted wavefront distortion (TWD) specification instead of a surface flatness. For more information on the difference between these two specifications, see our application note on Understanding Optical Windows.
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Typical transmission of a 3mm thick, uncoated N-BK7 window across the UV - NIR spectra. |
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Typical transmission of a 3mm thick N-BK7 window with MgF2 (400-700nm) coating at 0° AOI. The blue shaded region indicates the coating design wavelengh range, with the following specification: Ravg ≤ 1.75% @ 400 - 700nm (N-BK7) Data outside this range is not guaranteed and is for reference only. |
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Typical transmission of a 3mm thick N-BK7 window with VIS-EXT (350-700nm) coating at 0° AOI. The blue shaded region indicates the coating design wavelengh range, with the following specification: Ravg ≤ 0.5% @ 350 - 700nm Data outside this range is not guaranteed and is for reference only. |
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Typical transmission of a 3mm thick N-BK7 window with VIS-NIR (400-1000nm) coating at 0° AOI. The blue shaded region indicates the coating design wavelengh range, with the following specification: Rabs ≤ 0.25% @ 880nm Data outside this range is not guaranteed and is for reference only. |
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Typical transmission of a 3mm thick N-BK7 window with VIS 0° (425-675nm) coating at 0° AOI. The blue shaded region indicates the coating design wavelengh range, with the following specification: Ravg ≤ 0.4% @ 425 - 675nm Data outside this range is not guaranteed and is for reference only. |
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Typical transmission of a 3mm thick N-BK7 window with YAG-BBAR (500-1100nm) coating at 0° AOI. The blue shaded region indicates the coating design wavelengh range, with the following specification: Rabs ≤ 0.25% @ 532nm Data outside this range is not guaranteed and is for reference only. |
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Typical transmission of a 3mm thick N-BK7 window with NIR I (600 - 1050nm) coating at 0° AOI. The blue shaded region indicates the coating design wavelengh range, with the following specification: Ravg ≤ 0.5% @ 600 - 1050nm Data outside this range is not guaranteed and is for reference only. |
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Typical transmission of a 3mm thick N-BK7 window with NIR II (750 - 1550nm) coating at 0° AOI. The blue shaded region indicates the coating design wavelengh range, with the following specification: Rabs ≤ 1.5% @ 750 - 800nm Data outside this range is not guaranteed and is for reference only. |
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