Beam Splitter cubes:

There are many beam splitters in the market that have the form of a cube, where the separation of light of beam takes place at an interface within the cube. Two triangular prisms are used to create such a cube glued together with some transparent resin or cement. In order to adjust the power splitting ratio for a given length, the thickness of the layer is used. To modify the optical properties one can use some dielectric multilayer coating or thin metal coating on one or both of the prisms, e.g. In terms of operating bandwidth or polarization properties.

Since the interface present between the prism has a very low thickness, the transverse offset of the transmitted beam is very minimal. It becomes quite dangerous in some applications which is a reason for not using a partially transparent mirror at 45 degrees.

Not only just for the simple beams of light but beam splitter cubes can also be used also for the beams carrying images, e.g. In a variety of cameras and projectors. It is very mportant to do the cleaning optical mirrors in order to use them for the fiber optic polarization. The laser line polarizing cube beam splitters also requires cleaning of mirrors.

Generally, most of the cube beam splitters are not that much capable to tolerate a high optical power as beam splitters, although optically contacted cubes have the capabilities to handle these optical powers. The use of cube beam splitters is always favourable over the use of plates concerning handling and durability.

Non-polarizing beam splitter cubes

These types of cubes are generally created by simply refining the design with the help of a multi-layer coating between the prisms. A sufficient angle of incidence would naturally introduce a substantial polarization dependence, but there are certain design principles that can be used to minimize such effects, at least within some limited optical bandwidth. It is a point to note that the “non-polarizing” usually does not mean that such a cube preserves polarization.

Polarizing beam splitter cubes-

In order to create the Polarizing beam splitter cubes, crystalline media is used instead of glass, which can be birefringent. A variety of polarizing beam splitter cubes (polarizers) can be constructed because of this such as Wollaston prisms and Nomarski prisms, where the two output beams exit from the same side of the prism, and the angle between these beams is typically between 15° and 45°. There are some other types which include the Nicol Prism and Glan-Thompson Prism, the latter having a rhombohedral form.