Ophthalmic measuring instrument
OwnerMarc Jay Gannon, Daniel Lee Gunterinventors
Life of this patent
Estimating the term…
Abstract
A measuring instrument particularly adapted to making accurate measurements of portions of the eye and contact lenses is characterized by a split mirror system in which one mirror is fixed and a second mirror rotates upon movement of handle-pointer associated with a scale. The object to be measured is magnified, and the magnified image is split by the mirror system until opposite edges of the split image coincide, whereby a correlated linear measurement is indicated on the scale. The instrument includes a light to illuminate the work area and an attachment for measuring the diameter of contact lenses.
Claims16
An instrument for measuring a dimension between an object being viewed, comprising focusing means for viewing said object at a given distance, a pair of mirrors arranged in a common plane on an angle facing said object, one of said mirrors being fixed relative to said object, the other of said mirrors being rotatable relative to said one mirror, the image of said object being divided into a split image upon rotation of said other mirror out of planar relationship with said one mirror, means for rotating said other mirror, and means for correlating the relative degree of rotation of said other mirror to the dimension being measured.
A measuring instrument comprising a housing, magnifying lens means for magnifying objects externally of said housing, a pair of contiguous coplanar mirrors in said housing arranged to reflect the magnified image of said lens, one of said mirrors being fixed with respect to said lens and the other of said mirrors being rotatable out of coplanar relation with said one mirror, means for viewing the object reflected by said mirrors, manually operable means for rotating said other mirror, and means for measuring the degree of movement of said manually operable means.
A method of making a measurement of an object between points on opposite edges of said object, comprising the steps for providing a whole reflected image of said object upon a pair of coplanar contiguous mirrors, such that the juncture between the mirrors is in alignment with said points, rotating one of said mirrors while holding the other mirror fixed until the image is split and said opposite edges coincide, and measuring the degree of rotation of said one mirror in correlation with units of measure.
Dependencies are inferred from the claim text.