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.


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Ball & Half Ball Lenses

Ball lenses are key components in a wealth of applications due to their excellent collimation and focussing properties. Their small size, simple alignment, and complete rotational symmetry also mean they are a cost effective solution.

Knight Optical offers a range of competitively priced ball and half ball lens custom solutions to suit your requirements. We can offer diameters ranging from micro optics of 0.13mm in diameter up to larger 150mm diameters. All our ball and half ball lenses can be manufactured at different grades to ensure you are getting the specifications you need, these range from high precision grade 3 (with high sphericity and surface quality) to more commercial grade 100 ball lenses.

You can find more information on the grades we offer here.

Typical dimensions of the materials Knight Optical can offer are as follows:

Ruby 0.12-15mm
Sapphire 0.2 – 25.4mm
Fused Silica 0.3 – 25.4mm
Spinel 0.2 – 8mm
Cubic Zirconia 0.2 – 20mm
Alumina 99.9% & 99.5% 0.4 – 150mm
Zirconia Yttria 0.4 – 150mm
Silicon Nitride 0.4 – 25.4mm
Tungsten Carbide 0.13 – 25.4mm
Steel 0.13 – 25.4mm
Optical Glass – NBK7, LASFN, LASFN-35, LASFN-9 0.2 – 20mm
low thermal expansion glass – Zerodur upon request
Technical Glass – Borosilicate, Crystal Clear Sode – Black Soda – Red Glass 1 – 12.7mm

An antireflective (AR) coating can also be applied, such as telecom AR coatings in different wavebands between 830nm to 1600nm.

Contact ourtechnical sales team and discover how Knight Optical’s high quality, custom ball and half ball lenses, along with our impeccable level of service, can improve your instrumentation and supply chain experience.

Additional Information

A wide range of material options are available to cover UV to IR applications:

  • Materials with high refractive indices are often used as they produce a shorter back focal length and therefore higher efficiency fibre coupling, for example, S-LAH79 (2.003), LASFN9 (1.8502), LASFN35 (2.022) and LAH78 (1.9013).
  • Sapphire and ruby ball lenses are ideal where durability is required. Sapphire has an excellent transmission range from 200nm to 5µm and so can be used in UV, visible and NIR applications.
  • Silicon ball lenses are ideal for IR applications due to their excellent transmission from 1.2-15µm.
  • ball lenses can be used as preforms for moulded aspheric lenses and reduces the manufacturing process and related costs.


  • Ball lenses exhibit spherical aberration which means they are not ideal for imaging applications.
  • Typical Applications

    • Telecommunications industry to improve signal quality in bandwidth communications including fibre-to-fibre, diode-to-fibre, and diode-to-diode assemblies which demand efficient coupling and collimating optics.
    • LED traffic light systems to uniformly disperse the light
    • Endoscopy, bar code scanning, sensor applications
    • In modern LED traffic light systems, hemispherical (half ball) lenses are used to uniformly disperse light rather than collimate it. Half ball lenses can also be used in place of ball lenses where there are space constraints./li>

    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