Beam splitter cube 1
Beam splitter cubes usually consist of two 90° prisms and are used in optical metrology. The hypotenuse of a prism receives the dividing layer, then the two prisms are optically cemented to the hypotenuses. The division ratio 50:50, 60:40, 80:20 etc. is specified by the customer. The optical cement depends on the refractive index of the glass.