Polarization Beam Splitter

Polarizing Beamsplitters (PBS) splits incident unpolarized light into two perpendicular linearly polarized light. Among them, p-polarized light passes through completely, while s-polarized light is reflected at 45 deg which makes the emitting direction of s-light vertical to p-light. Additionally, beamsplitters can be used in reverse to combine two different beams into a single one. Beamsplitters are often classified according to their construction:cube or plate.

Cube PBS are fabricated using two typically right angle prisms. The hypotenuse surface of one prism is coated, and the two prisms are cemented together so that they form a cubic shape. 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.

Plate PBS consist of a thin, flat glass plate that has been coated on the first surface of the substrate. Most plate beamsplitters feature an anti-reflection coating on the second surface to remove unwanted Fresnel reflections. Plate beamsplitters are often designed for a 45° AOI.

WISOPTIC offers both cube PBS and plate PBS for a variety of wavelength ranges and power handling requirements. In addition, birefringent crystals, Brewster windows, and waveplates are also available for high laser damage threshold requirements.