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BREXIT UPDATE: Knight Optical will continue to provide quality assured service for all your optical requirements both custom & stock. We will handle all requirements caused by the new regulations.


Looking For a Custom Optical Solution? Enquire


Nanotechnology optical components


Sapphire is one of the most commonly used optical materials – and not by coincidence. Listed below are some of the numerous reasons why sapphire may offer the custom optical solution you need:



  • Sapphire is ranked at 9 on the Mohs scale of hardness and boasts a very high modulus of rupture, meaning that this material is both difficult to scratch and able to withstand extreme pressure. Applications include rugged environments such as submarine viewing windows.
  • The melting point of sapphire is 2040 °C, enabling its use in furnaces and other high temperature environments.
  • As chemically inert and with significant electrical resistance, sapphire can be used in contact with highly reactive substances such as fluorine plasma
  • Sapphire transmits from the UV up to MWIR wavelengths (0.17-5.5µm) with impressive internal transmittance across the same range (up to 97%).
  • Sapphire is available in random cut, C-cut and fluoresce-free varieties. Knight Optical is able to verify the material axis by use of a polarimeter (C-cut shown in the image to the right).

Sapphire can be polished to a high standard, but as it is the second hardest mineral on Earth it must be subject to high forces in order for this to be achieved. Therefore, highly polished windows made from Sapphire must have a thickness to diameter ratio of at least 10:1, that is, greater than 10mm thick for a 100mm diameter disk.

Our custom capabilities, tolerance information and transmission data is available below. Contact our multilingual technical sales team and discover how Knight Optical’s high quality, custom sapphire optics along with our impeccable quality of service can improve your instrumentation and supply chain experience.

Our 2018/2019 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.

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