Specification:Model: DN20FL50.8Material: ZnSeDiameter: 20mmFocal Length: 50.8mmEdge Thinckness: 2.2mmAperture: 90% of the DiameterTolerance of Thickness ±0.25mmTolerance of Diameter: +0/-0.13mmEffective Focal Length: ±2%Anti-Reflective Coating: at 10.6 μmSurface Quality: 40-20Surface Figure at 0.63 μm: λ/2 per 1 inch DiaCoating Transmittivity Per surface at 10.6 μm: ≥99.50%Features:- ZnSe is used for optical windows, lenses, mirrors, prisms and optical blanks, plates, disks, sheets, slabs particularly for infrared applications- Zinc Selenide (ZnSe) is transparent in wide spectral range from yellow (visible) to far IR. ZnSe material is a chemically inert, non-hygroscopic and highly pure product that is very effective in many optical applications due to its extremely low bulk losses, high resistance to thermal shock and stability in virtually all environments, easily machined.- To obtain superior transmittance, ZnSe crystals are grown by Chemical Vapor Deposition process. Zinc Selenide is polycrystalline material, demonstrates superior CO2 laser transmittance and is employed in the transmission optical components used in CO2 laser processing.Package Included:1 × DN20FL50.8 ZnSe Focus LensMore Details:
You may return most new, unopened items within 30 days of delivery for a full refund. We'll also pay the return shipping costs if the return is a result of our error (you received an incorrect or defective item, etc.).
You should expect to receive your refund within four weeks of giving your package to the return shipper, however, in many cases you will receive a refund more quickly. This time period includes the transit time for us to receive your return from the shipper (5 to 10 business days), the time it takes us to process your return once we receive it (3 to 5 business days), and the time it takes your bank to process our refund request (5 to 10 business days).
If you need to return an item, simply login to your account, view the order using the 'Complete Orders' link under the My Account menu and click the Return Item(s) button. We'll notify you via e-mail of your refund once we've received and processed the returned item.
We can ship to virtually any address in the world. Note that there are restrictions on some products, and some products cannot be shipped to international destinations.
When you place an order, we will estimate shipping and delivery dates for you based on the availability of your items and the shipping options you choose. Depending on the shipping provider you choose, shipping date estimates may appear on the shipping quotes page.
Please also note that the shipping rates for many items we sell are weight-based. The weight of any such item can be found on its detail page. To reflect the policies of the shipping companies we use, all weights will be rounded up to the next full pound.