Esco Optics, Inc.

Precision Flat Windows, N-BK7 Optical Glass*

Precision Flat Windows, N-BK7 Optical Glass* - Main image
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$30.12 $40.7 In stock

Category: Precision Flat

Our precision N-BK7 laser quality round windows range from 0.25 waves (λ/4) to 0.10 wave (λ/10) flat. Catalog parallel specifications are either 5" arc seconds or 10' arc minutes. Ideal for interferometer flats, laser windows, beamsplitter substrates, and parallel plates. N-BK7 Optical Glass or equivalent glass.* Indicate in order notes if N-BK7 is required.

Note: Flatness and Paralellism units are are expressed as (waves - arc min)

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    Customer Reviews (4.8 / 5 · 5 reviews)

    Avery Q. ★★★★★

    The 5 arc second parallelism spec held up perfectly when I tested it on my autocollimator; the surfaces are so clean I didn't even need to re-clean them before mounting. This is the third λ/10 window I've bought for my lab and the consistency is reassuring.

    Riley ★★★★★

    Swapped the λ/10 version into my interferometer setup and the fringe pattern cleaned up immediately — way flatter than the generic windows I'd been fighting with. Edge finish is clean too, no chips or sleeks out of the box.

    Brian ★★★★★

    The λ/10 flatness on these windows is incredible for the price—my interferometer readings were spot on. Even the 5 arc second parallelism held up perfectly in my setup.

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