Europe, UK, Asia & RoW: [email protected] +44 (0)1622 859444 | USA & Canada: [email protected] +1 401-583-7846

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

Custom Beamsplitters

cube beamsplitter, plate beamsplitter, beamsplitter coating, polarising beamspliiter, non polarising beamsplitter, custom beamsplitterKnight Optical can supply custom optical beamsplitters that work in the UV, visible and IR wavebands. We can provide plate and cube beamsplitters manufactured to your meet your spectral and dimensional specifications.
We can provide both polarising and non-polarising beamsplitters in plate and cube forms. A standard, non-polarising beamsplitter is designed to split the light beam into a specific reflection/transmission ratio, such as a 50/50 split. Knight Optical can provide bespoke beamsplitter coatings with a R/T ratio that suits your application.
A polarising beamsplitter is designed to split the incident beam by its polarisation states, where the S polarisation is reflected and the P polarisation is transmitted. We can supply polarising beamsplitters with a high extinction ratio (Tp:Ts).
Knight Optical can also supply more specialist beamsplitters, such as polka dot beamsplitters and dichroic beamsplitters.
For a quick turnaround on custom dimensions, Knight Optical holds a stock of beamsplitter sheet material with the following coatings:

beamsplitter coating, visible wavelength, 50 50 split

Beamsplitter 50/50 @ 450-680nm VIS

beamsplitter coating, NIR wavelength, near infrared beamsplitter, 50 50 split

Beamsplitter 50/50 @ 530-1070nm NIR

beamsplitter coating, NIR wavelength, telecom wavelength, 50 50 beamsplitter

Beamsplitter 50/50 @ 1050-1700nm NIR Telecom

beamsplitter coating, visible wavelength, 30 60 split

Beamsplitter 33/67 @ 450-700nm VIS

beamsplitter coating, visible wavelength, 40 60 split

Beamsplitter 40/60 @ 400-700nm Economy

Contact our sales team who can provide further information and help you with your enquiry.
You can find more information on the different beamsplitters available below:

Additional Information

  • It is worth noting that plate beamsplitters, which work at a 45° AOI, exhibit an offset to the transmitted beam and the degree of shift is dependent on the thickness and refractive index of the substrate used. This can be problematic for alignment in some applications.
  • A cube beamsplitter can be easier to integrate into a system and exhibits minimal offset to the transmitted beam.
  • Crystalline birefringent materials can be used as a type of polarising beamsplitter, such as Wollaston prisms and Glan-Taylor prisms. In a Wollaston prism, consisting of two calcite prisms, the two linearly polarised beams are both transmitted through the exit face.
  • Germanium can be used as a natural 50/50 beamsplitter for infrared wavelengths, specifically 2 to 14µm, due to its high refractive index.


Knight Optical can also apply a wide range of coatings to your optical windows to enhance their transmission or increase their durability:

  • Antireflective (AR) coatings, including broadband coatings, to optimise the transmission at certain wavelengths or across a range.

Quality Assurance

  • Transmission and reflection scans are conducted on our Agilent Cary 7000 Spectrophotomer which can perform spectral scans at multiple angles of incidence and different polarisations, ASCII data and graphs can be provided.
  • The flatness and irregularity of optical beamsplitters, if required, are tested on our Zygo Verifire XPZ interferometer, where we can also test the transmitted wavefront error.
  • We check the parallelism on our Trioptics PrismMaster which is accurate to 3 arc seconds.
  • We can also test infrared optical components on our Agilent Cary 660 FTIR spectrometer.
  • All optics are 100% visually inspected before packaging, our staff are trained to ISO 10110 and MIL-0-13830A, and can check down to 10/5 scratch/dig which is especially critical in laser applications.


  • Standard beamsplitters that split unpolarised light into a R/T ratio are commonly used in interferometers to direct light down two paths – a reference path and toward the sample.

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