Getting to know the popular beamsplitters
Posted by juliabennet on July 27th, 2013
Beamsplitters represent optical devices that can split a certain light beam in two or, on the contrary, bring back together several beams of light. As a major compound in the working process of interferometers, they can have a plate or cube shape. In the second circumstance, the beam splitter is made, in fact, from two prisms bound together while following certain specifications. Do you think that this is all there is to know about this optical technology?
In order to make a short comparison in between the two main types, we should look into the particularities of every single one. For starters, the plate models are made from a flat plate of glass which is incredibly thin and that receives a layer of antireflection coating on one of its sides. Cube models bring together two pieces of right-angled prisms, obtaining a cube shape. The alignment is set by applying a thin layer of cement on the surface of the hypotenuse.
Easy to imagine, both types of beamsplitters come with their own strengths and weaknesses. The cubes have no beam shift whatsoever, they considerably shorten any system’s optical path, they allow facile integration with 0 degrees AOI and they involve equal path lengths for both the reflected and the transmitted optical route! The plate models on the other hand present lightweight, are very easy to build even for larger sizes and their tag prices are not very expensive.
The challenges of setting a cube beam splitter on the other hand involve the difficulty of construction for larger projects and the production costs. As for the plate ones, they require different lengths for the path of the transmitted and reflected optical routes, extra work for the alignment of 45 degrees AOI and the transmitted beam light may easily shift over the process.
Weighting the pros and cons for both categories, it turns out that cube beamsplitters make a better choice than the plate opponents do, in general. Even so, they both continue to exist on the market for some very good reasons.
If you ask a specialist about your options, chances are you will be presented a much longer list with types of beam splitters. In the optical industry, they can classify them into dielectric mirrors, cubes – the one we have already talked about - , fiber optic models, metal coated mirrors, micro – optic splitters, pellicles or even waveguide splitters, which have a major utility in terms of photonic integrated circuits.
No matter if you want to go for the versions that include prisms or not, what matters more than the shape itself are the main properties of every single option. When you think you have understood them all, you might be surprised to discover that there is also the possibility to combine several beams into a single one. Of course, this new field involves fighting with interference phenomenon and struggling to output as much power and the one used for the input! Again, you should discuss all these aspects with professionals and having at least a tiny clue about them will make you feel a lot better.
Beamsplitters made of prisms or not, they all involve complicated technologies. Get in touch with a manufacturer today for further details!
