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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


Knight Optical is able to supply custom optical beamsplitters for use in the UV, visible, NIR, and IR wavebands. The custom optical beamsplitters that are available include:

Custom plate beamsplitters are available in various quality and R/T ratios. Custom standard ranges of beamsplitters are manufactured from sheet white float glass substrates and generally available in thickness of 1,2 and 3mm thk. Our custom quality grade beamsplitters are precision polished substrates manufactured from suitable material to meet required wavelength performance. The custom precision ranges have two extremely parallel and flat surfaces with high degree of surface scratch dig quality. One surface is coated with a thin film that reflects and transmits the required ratio, such as 25/75 to 75/25. The second surface is anti-reflection coated to minimise the reflection and the double image in the reflection plane. The coatings are designed for use at 45° and to have a broad bandwidth that covers the wavelengths of interest, for example, UV, visible, or NIR and FIR wavelengths.

Knight Optical’s custom cube beamsplitters
divide the input beam into two orthogonal beams of, for example, equal intensity across the range of the broadband coatings applied to the input and output surfaces together with the 45° interface. The cube will produce the two orthogonal rays with the same optical path length, which is critical in, for example, interferometry work. Custom cube beamsplitters have anti-reflection coatings s on the input and output surfaces with the centre interface having the thin film coating to reflect and transmit the input beam. The coatings can be designed to provide a polarising, or non-polarising, split of the beam with the intensities equal. The intensities can be designed to be at a different ratio, such as, 70/30, but this would be for the non-polarising cubes. The custom polarising cubes have maximised the reflected and transmitted beams so that they are near 99% for the s- and p- polarisation respectively.

These custom cube beamsplitters can be made to any ratio of splitting and across broadband or bandpass filter wavelengths. Suitable substrate for custom beamsplitter includes, for example, N-BK7 or equivalent, sapphire, UV grade fused silica, calcium fluoride, and barium fluoride can be used that match the wavelengths that the beamsplitter is designed for.

Knight Optical supply high quality custom beamsplitters made to our exact specification.
Every component is individually tested on our Agilent Cary 5000 spectrometers fitted with a UMA device for testing coatings in transmission and reflection at any given angle. We also have a DRA device fitted for testing complex beamsplitter components. Our Agilent 660 FTIR spectrometer is used for coatings between 3.5µm and 45µm. All tested by our highly skilled technicians in our state of 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 beamsplitters and service can improve your instrumentation and supply chain experience.

Our 2021/2022 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.
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