Arrangements of mirrors or prisms used as camera attachments to photograph stereoscopic image pairs with one lens and one exposure are sometimes called "beam splitters", but that is a misnomer, as they are effectively a pair of periscopes redirecting rays of light which are already non-coincident.OverviewA beam splitter or beamsplitter is an that splits a beam of into a transmitted and a reflected beam. It is a crucial part of many optical experimental and measurement systems, such as In its most common form, a cube, a beam splitter is made from two triangular glass which are glued together at their base using polyester,, or urethane-based adhesives. (Before these synthetic,.