• Non-Polarizing-Cube-Beam-Splitter-1

Cube Beamsplitters

Cube beamsplitters are made by two right angle prisms cemented together on the hypotenuses, the hypotenuse surface of one prism is coated. To avoid damaging the cement, it is recommended that the light be transmitted into the coated prism, which often features a reference mark on the ground surface shown in the following reference drawing. Cube beamsplitters have several advantages over plate beamsplitters, for example they are easier to mount and avoid ghost images due to a single reflecting surfaces.

Paralight Optics offers cube beamsplitters available in polarizing or non-polarizing models. The polarizing cube beamsplitters will split light of s- and p-polarization states differently allowing the user to add polarized light into the system. Whereas the non-polarizing cube beamsplitters are designed to split incident light by a specified split ratio that is independent of the light’s wavelength or polarization state. Even though non-polarizing beamsplitters are specifically controlled not to alter the S and P polarization states of the incoming light, given the randomly polarized input light, there will still be some polarization effects, that means there is difference in reflection and transmission for S and P pol., but they depend on specific beamsplitter type. If polarization states are not critical for your application, we recommend using non-polarizing beamplitters.

Non-polarizing beamsplitters basically split light into a specific R/T ratio of 10:90, 30:70, 50:50, 70:30, or 90:10 while maintaining the incident light’s original polarization state. For example, in the case of a 50/50 non-polarizing beamsplitter, the transmitted P and S polarization states and the reflected P and S polarization states are split at the design ratio. These beamsplitters are ideal for maintaining polarization in applications utilizing polarized light. Dichroic Beamsplitters split light by wavelength. Options range from laser beam combiners designed for specific laser wavelengths to broadband hot and cold mirrors for splitting visible and infrared light. Dichroic beamsplitters are commonly used in fluorescence applications.



Substrate Material:

RoHS Compliant

Coating Options:

All Dielectric Coatings

Cemented by:


Design Options:

Custom Design Available


Common Specifications:


Reference Drawing for

Cube Beamsplitter

The dielectric beamsplitter coating is applied to the hypotenuse of one of the two prisms, AR coating on both input and output faces.


Ranges & Tolerances

  • Type

    Non-polarizing cube beamsplitter

  • Dimension Tolerance

    +/-0.20 mm

  • Surface Quality (Scratch-Dig)

    60 - 40

  • Surface Flatness (Plano Side)

    < λ/4 @632.8 nm

  • Transmitted Wavefront Error

    < λ/4 @632.8 nm over clear aperture

  • Beam Deviation

    Transmitted: 0° ± 3 arcmin | Reflected: 90° ± 3 arcmin

  • Chamfer

    Protected < 0.5mm X 45°

  • Split Ratio (R:T) Tolerance

    ±5% [T=(Ts+Tp)/2, R=(Rs+Rp)/2]

  • Clear Aperture

    > 90%

  • Coating (AOI=45°)

    Partially reflective coating on hyphtenuse surfaces, AR coating on all entrances

  • Damage Threshold

    > 500mJ/cm2, 20ns, 20Hz, @1064nm



Our non-polarizing cube beamsplitters cover the wavelength ranges of Visible, NIR, and IR ranges, split ratios (T/R) include 10:90, 30:70, 50:50, 70:30, or 90:10 with a minimal dependence on the polarization of the incident light. Please contact us for more details if you are interested in any of beamsplitters.


50:50 Cube Beamsplitter @650-900nm at 45° AOI


50:50 Cube Beamsplitter @900-1200nm at 45° AOI