Measuring set for determination of the sagittal depth and the average central curvature of gel contact lenses
AssigneeCeskoslovenska akademie ved
InventorsOtto Wichterle, Jiri Svantner
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AssigneeCeskoslovenska akademie ved
InventorsOtto Wichterle, Jiri Svantner
Estimating the term…
The invention pertains to a measuring set for determination of the sagittal depth and the average central curvature of soft contact lenses which consists of two measuring units based on the principle of depth gauges and the common electronic indication part. The apparatus serves for rapid and inexpensive selection of the correct contact lens according to the shape and peculiarities of the patient eye. Each measuring unit consists of a fixed part formed by a support plate, a stable conductive hollow screw, and a coaxially fitted conductor insulated from the screw and protruding above the insulation, and a movable part formed by a conductive nut bearing an insulation bushing for the protruding conductor and a scale and put on the screw.
Apparatus for detecting sagittal depth and average curvature of gel contact lenses comprising a first and second measuring unit, each of which having a fixed support plate, a hollow conductive screw post fixedly secured to said support plate and extending perpendicular thereto, a rotatable lens support comprising a central boss and an integral disc extending radially therefrom, said boss being matingly threaded on said screw post, the boss of said first unit being formed of a frontal face adapted to receive a lens thereon about its peripheral edge, the nut of said second measuring unit being formed of an annular edge of a diameter adapted to seat the lens thereon substantially about the periphery of the corneal part of said lens, a conductive wire insulatingly secured in fixed position coaxially within said screw and extending outwardly of the end thereof by a predetermined distance, said conductive wire extending freely through said boss in opposition to the center of said lens, said lens being movable toward and away from the tip of said wire on rotation of said lens support, and an electronic conductivity indicator having a pair of inputs connected respectively to said conductive screw post and said conductor wire and forming a circuit on engagement of said lens with said wire.
Dependencies are inferred from the claim text.