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Optical Beamsplitters

High-quality beamsplitter plates, DST Series

Special Properties & Features

  • Neutral splitting of light, images, and laser beams
  • Anti-reflection coated on the backside
  • Free of double image or phantom laser beam effects
  • Metal-free dielectric optical coating
  • Low light-loss
  • Broadband coating design for random polarization
  • High optical precision
  • Large dimensions available (DST500)

Typical Applications

  • Optical reference measurement systems
  • Laser beamsplitters in optical benches
  • Semi-transparent mirrors for interferometer systems
  • Splitting or merging of optical beam paths
  • Sensor technology
  • Fiber optical applications
  • Image processing and machine vision
  • Photonics research
  • Beamsplitter plates in optical instruments
  • Laser beam combiners
  • Optical measurement technology
  • Divider mirrors for imaging applications

Related optics

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Optics manufacturing within 48h Also available in 48 h Express-Service

Optical beamsplitters allow incident light or a laser beam to be split into two optical paths. They reflect a certain proportion of the incident light like an optical mirror with an angle of incidence of 45° and at the same time allow the remaining light to pass through in the 0° direction. The multilayer dielectric thin film coating applied to the input side of the beam splitter determines the optical splitting ratio. Plate beamsplitters used to split a laser beamIn addition, a broadband anti-reflection coating on the back of the beam splitter prevents unwanted secondary reflections. A so-called "ghost image" or a phantom laser beam, which can emerge with beamsplitters without anti-reflective coating on the back, does not occur. Also, light loss caused by reflections from the backside of the optics reduces to a minimum.

Unlike dichroic beamsplitters, such as our SIR filters or SHD mirrors, the DST-splitter works neutrally. Instead of separating different optical wavelength ranges, it splits a visible light beam or an image color neutral. The non-metallic coating construction of our DST-beamsplitter plates ensures excellent durability and high abrasion resistance. Their dielectric layer system exhibits only negligible light absorption in the nominal wavelength range. Hence, in contrast to metallic beamsplitters that usually absorb a large amount of the incidence light, such energy losses are minimal. The DST can also work as a splitter for a laser beam with up to medium laser power. Hence, many customers use them in reference measurement systems and optical benches.

We designed all our optical DST-beamsplitters for light without defined polarization. When using a polarized light source or a laser, the real-world splitter's ratio may deviate from the specifications given here. We only specify the ratios for random polarization, and we don't define them in terms of polarizing effects. However, this does not generally exclude optical applications with polarized light sources. You can often achieve the desired division by selecting a higher or lower already existing splitting ratio. In such cases, the cost is drastically reduced compared to a batch of custom coated beamsplitters.

If you need beamsplitter optics for polarized light or laser beam applications, please contact us and provide information on your application's wavelength, required splitting ratio, and other relevant details. We can coat optics with custom ratios according to individual specifications in addition to our standard beamsplitters from the DST300, DST500, and DST700 series. Please use our inquiry form to contact us for technical assistance, further information, or help with your customized beamsplitter optics.


How can I order the DST-plate beamsplitters?

You won't find a shopping cart on our website because we are not limited to standard optics with fixed dimensions. Our company specializes in the rapid manufacturing and delivery of our optical beamsplitters with customized sizes. We often ship tailor-made beamsplitters just as fast or even faster than stock items usually ship. Moreover, this also applies to large production quantities! You will usually receive our quote within a few minutes, provided you are in our time zone and we have no queries.

To get a quote for our broadband optical plate beamsplitters with custom dimensions, please choose a thickness from the table or click the button below.


Request for Quotation


Customized optics manufacturing within 48h Also available in 48 h Express-Service



DST300 beamsplitters
DST300, spectral transmittance curve
Enlarge transmission curve of the DST300

DST500 beamsplitters
DST500, typical transmittance
Enlarge transmission curve of the DST500

DST700 beamsplitters
DST700, typical spectral transmittance
Enlarge transmission curve of the DST700

Standard Thicknesses

(Please click on a thickness to get a quote)

Thickness (mm)


48h-Express Service
DST300 beamsplitter
R:T = 70:30
1,00 ±0,10
DST500 beamsplitter
R:T = 50:50
1,00 ±0,10
DST500T beamsplitter
R:T = 50:50
3,30 ±0,20
DST700 beamsplitter
R:T = 30:70
1,00 ±0,10
Other thicknesses on request.
The thicknesses marked with "" are also available within 48–h Express Service.


  • Up to max. 630 mm x 810 mm

Splitting ratios for 45° angle of incidence

(All specifications for random polarization)

DST300 plate beamsplitters
  • R/T = 70/30 (± 10%) for 450-650 nm
DST500 plate beamsplitters
  • R/T = 50/50 (± 6%) for 450-650 nm,
    R/T = 50/50 (± 10%) for 430-685 nm
DST500T plate beamsplitters
  • R/T = 50/50 (± 10%) for 450-650 nm
DST700 plate beamsplitters
  • R/T = 30/70 (± 8%) for 450-650 nm,
    R/T = 30/70 (± 10%) for 400-700 nm
Different beam splitting ratios, angles of incidence, and wavelength ranges are possible on demand.

Coating Construction

Substrate Materials


  • Depending on the material, thickness, and shape

Damage Threshold

  • Depending on the laser beam diameter and laser power
    (Please send an inquiry if relevant)

Surface Quality

  • Better than 80-50 scratch & dig (MIL-0-13830A)
  • Different surface qualities per inquiry

Other Specifications

  • Adherence according to MIL-C-675 C (tape test)
  • Abrasion-resistance referred to MIL-M-13508 C

Note: If you search for cube-beamsplitters, beamsplitter-prisms, non-polarizing beamsplitter cubes, or cube beamsplitters for other wavelength areas, please send us a detailed request with all specifications and requirements. Such kinds of optical components are always custom-made and require minimum batch quantities.


All given details and specifications are mean reference values and are not guaranteed. Also, please consider our "Notes on technical specifications".

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