Polarizer: An optical device which converts natural or un-polarized light into polarized light by selective absorption of rays in one direction, and passing of rays perpendicular to the polarizing medium. Usually fabricated from stretched plastic sheets with oriented, parallel bi-refringent crystals.
Auxillary Viewing Port: Provides a second output port for an additional camera or for direct vision using an eyepiece. A 50/50 beam splitter cube is used for minimal image degradation. This assembly has an optical path length so only the right angle adapters will provide a parfocal image. Adapters are required in both vertical and horizontal viewing arms.