Vertometer

Vertometer was the trade name of an instrument made by Bausch & Lomb (B&L) and later by Reichert. Lensometer was the trade name of the nearly similar instrument made by American Optical. Neither the Vertometer or the Lensometer is now being made. Lensmeter is a generic name that can be applied to any lens measuring instrument. 'A vertometer' is an ophthalmic bench instrument used to measure dioptric power of a lens. It differs from a lensmeter or lensometer which is a general dispensary tool for opticians to verify spectacle prescriptions at the laboratory. A vertometer, on the other hand, is a more precision instrument used to locate, mark, and index a lens optical center for edging, mounting, and construction of a spectacle prescription.