OptiVISOR
From Wikipedia, the free encyclopedia
An OptiVISOR is a Optical Magnification Precision device manufactured by Donegan Optical Company in Lenexa, Kansas. It is used by jewelers, engravers, architects, physicians and most other occupations that require significant magnification.
OptiVISOR should be worn squarely on the head with the center of the lens plate at the bridge of the nose. By adjusting the knob at the rear of the unit, enough tension can be applied to hold the headband in place. The adjustable pivots on either side of the unit should also be tightened with tension to hold the lens in front of the eyes as well as up out of the path of vision when not in use.
The lens plate of the OptiVISOR consists of two individual magnifying lenses manufactured from a controlled index of refractive crown glass. The lenses are ground and polished to the same precision standards of opthalmic eyeglass lenses. The purpose of the "prismatic" lens is to assist both eyes to converge on the object being viewed at a closer than normal distance as necessary for magnification.
