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Silicon Windows

Silicon (Si) is one of the hardest minerals and optical materials available for use in the NIR (1µm) to about 6µm.  Optical quality Silicon is usually doped (5 to 40 ohm cm) to prevent absorption bands within the transmission waveband.  Silicon has a lower refractive index than germanium and has a lower density that makes for less weighty optical designs.

Silicon is ideal for use as windows in the 3 to 5µm (MWIR) waveband and as substrate for optical filters. We stock a range of silicon windows and also offer a range of custom silicon window options from 5mm to 300mm diameter and thickness to 50mm.  Our custom silicon windows can be polished to ¼ wave and for imaging high quality applications we provide surface quality of better than 10-5 scratch dig.  Custom silicon windows can be manufactured and supplied uncoated or with antireflective coating.  A range of DLC/AR coatings are also available.

Every component is individually tested by our highly skilled technicians in our state of the art metrology lab to ensure all components meet our high quality standards. Contact our multilingual technical sales team and discover how Knight Optical’s high quality custom silicon windows and service can improve your instrumentation and supply chain experience.

View “available stock” tab for a range of quality stock silicon windows uncoated and antireflective coated @3-5µm in a range of diameters and thicknesses to meet most applications.  If you require sapphire windows to a smaller size or a custom aperture we are able to machine our stock windows at short notice, please enquire.

Our 2022/2023 Catalogue

Inside Knight Optical’s catalogue you’ll find details of the industries we serve as well as the many other services we can offer. It also showcases hundreds of our most popular products, supported by useful technical information, to help you choose the right part for your application.
Click below to view our digital catalogue now.

view our catalogue