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Beamsplitter Plates

High-quality plate beamsplitters, DST Series

Special Properties & Features

  • Color neutral splitting of images and laser beams
  • Anti-reflection coated back-side
  • No double image or phantom laser beam
  • Low energy loss due to all-dielectric construction
  • Metal-free thin-film coatings
  • Designed for random polarization
  • High optical quality
  • Large dimensions possible (DST500) NEW!

Typical Applications

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

Related optics

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

Beamsplitter plates split an incident image or a laser into a transmission and reflection component. They reflect a specific part of the incident light like an optical mirror and transmit the remaining part like an optical window.

Plate beam splitters used as laser beam divider optics

By applying a multi-layer dielectric thin-film coating to the input side, we determine the splitting-ratio of our DST plate beamsplitter optics. On the reverse side, we deposit a broadband anti-reflection layer to eliminate secondary reflections. "Ghost images" and phantom laser beams that occur with beamsplitters without anti-reflection coating on the back are thus avoided. Energy loss caused by reflections from the backside of the optics is reduced to a minimum.

Unlike dichroic beamsplitters, such as our SIR filters or SHD mirrors, our DST beamsplitters work in a mostly color-neutral way. Instead of separating different optical spectra from each other, they split light with a visible wavelength neutrally.

The non-metallic construction of the optical coating of our beamsplitter plates ensures excellent durability and high abrasion resistance of the optics. Also, the dielectric layer system of the splitter mirrors exhibits only low optical absorption in the nominal wavelength range. In contrast to metallic beamsplitters that usually absorb a large portion of the incidence light, losses are minimal. Hence, you can also use our DST-beamsplitters to split laser beams with up to medium laser power. In laser applications, one part of the laser beam is mirrored by 45°, while the rest of the beam is transmitted at 0° (see figure above). This function is a typical requirement for beamsplitters in reference measurement systems or the use in optical benches.

We designed all DST-beamsplitters for light without defined polarization, i.e., non-polarized light. When using our DST-beamsplitters with polarized light sources or with a polarized laser beam, the optical splitting-ratio may deviate from the specifications given here. We only specify them for random polarization. The DST beamsplitter plates are also not defined in terms of polarizing effects. However, this does not generally exclude optical applications with polarized light sources. The desired gradation can often be achieved by selecting a higher or lower existing ratio of the optics. The cost can be drastically reduced compared to a batch of custom coated plate beamsplitters. If you need splitter optics for polarized light or a polarized laser beam, please contact us and provide information on wavelength, splitting-ratio, and all relevant details of your application.

In addition to our high-quality standard beamsplitters, the DST300, DST500, and DST700 series, we can coat optics with splitting-ratios according to custom specifications. Please use our inquiry form to contact us for technical assistance, further information, and 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. We are specialized in the rapid manufacturing and delivery of our optical plate beamsplitters with customized sizes. We often ship tailor-made beamsplitters just as fast or even faster than stock items are shipped usually. Moreover, this also applies to large production quantities! As a rule, you receive our quotation within a few minutes, provided you are in our time zone, and there are no queries.

To request a quote for our high-quality optical plate beamsplitters with custom dimensions, please choose a thickness from the table or click the button below.


Request for Quotation


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



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

DST500 beamsplitters
DST500, typical transmittance
Enlarge transmission curve of DST500

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

Standard Thicknesses

(Please click on a glass thickness to request a quote)

Thickness (mm)


48h-Express Service
DST300 plate beamsplitter
R:T = 70:30
1,00 ±0,10
DST500 plate beamsplitter
R:T = 50:50
1,00 ±0,10
DST500T plate beamsplitter
R:T = 50:50
3,30 ±0,20
DST700 plate beamsplitter
R:T = 30:70
1,00 ±0,10
Custom thickness 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 division ratios and incident angles 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 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
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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