Precision glass windows-BK7 type (λ/4) These Precision Glass Windows are optically-polished with parallel faces and are useful not only as windows but as substrates for special beamsplitters etc. These Precision Glass Windows are offered uncoated, AR-coated for ranges covering both visible and NIR (450-900nm). As these windows have parallel faces they are ideal for applications that require minimal transmitted beam deviation.
Knight Optical > Windows > BK7 Window - Quality Grade (Lambda/4) > Diameter Only UK and EU customers are charged VAT at 17.5%, customers outside the EU and EU customers based outside the UK who have a valid EU VAT number will not be charged VAT Bulk Discounts! Where (B) appears next to a price below, bulk prices are available, click the (B) button to view! PDF Part No. Material Diameter (mm) Thickness (mm) Price Qty Buy WQK1000 BK7 10 3 £11.00 WQK1500 BK7 15 3 £9.95 WQK2500 BK7 25 6 £12.95 WQK2501 BK7 25.4 6.35 £11.85 WQK4000 BK7 40 6 £18.00 WQK4000-C BK7 40 (with CofC) 6 £28.50 WQK5000 BK7 50 6 £24.60 WQK6500 BK7 65 8 £38.85 Knight Optical > Windows > BK7 Window - Quality Grade (Lambda/4) > Diameter
Specification   Material: BK7 Material Data: (see materials section) Diameter: +0, -0.15mm Length, width: ±0.1mm Thickness: ±0.1mm Flatness: λ/4 over 90% of aperture dimensions Scratch-dig <40-20 Parallelism <30 arcsec
Specific requirements We can manufacture Precision BK7 glass windows to any size at short notice, so if your requirements are not listed please contact us by telephone / fax or email: stockrequirement@knightoptical.co.uk Options available   · Mounting (circles up to 50mm dia.)   · Other coatings   · Edging to smaller diameters See also Optical flats