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A scleral lens is a prototypical lens dating back to the early 1880s. Originally these lenses were designed by using a substance to take a mold of the eye. Lenses would then be shaped to conform to the mould, initially using blown glass and then ground glass in the 1920s and polymethyl methacrylate in the 1940s. [ 7 ]
Scleral lens, with visible outer edge resting on the sclera of a patient with severe dry eye syndrome. A scleral lens is a large, firm, transparent, oxygen-permeable contact lens that rests on the sclera and creates a tear-filled vault over the cornea. The cause of this unique positioning is usually relevant to a specific patient whose cornea ...
The T-mount is a standard lens mount for cameras and other optical assemblies. The usual T-mount is a screw mount using a male 42×0.75 (42 mm diameter, 0.75 mm thread pitch) metric thread on the lens with a flange focal distance of 55 mm and a mating female 42mm thread on a camera adapter or other optical component.
Canon New FD lens mounting surface.. The FD lens mount is a breech-lock mount, which is a variation of the common triple-flanged bayonet attachment. The advantage of the breech-lock over the bayonet is that neither the contact surfaces between the body and lens, nor the signalling mechanisms, rotate against each other when the lens is mounted.
August Müller (1864 – 1949), born in Mönchengladbach, was a medical student at the University of Kiel, Germany, and a pioneer in the manufacture of contact lenses.In 1889, he presented at the university his doctoral thesis titled Eyeglasses and corneal lenses [1] [2] in which he described his efforts to grind scleral lenses from blown glass.
Eugène Jean Baptiste Kalt (24 February 1861, in Landser, Haut-Rhin – 9 May 1941) was a French ophthalmologist who developed the first known application of a contact lens for the correction of keratoconus. In 1888, he worked on a crude flat-fitting glass scleral lenses designed to "compress the steep conical apex thereby correcting the ...
The gold-plated electronic contacts of an EF-mount lens. Canon introduced the EF-lens mount in 1987 as part of the EOS system. It broke with the most common technique for implementing autofocus at that time by not having a mechanical connection to a motor in the camera body, having instead only electrical connections and requiring a motor to be ...
The M42 lens mount is a screw thread mounting standard for attaching lenses to 35 mm cameras, primarily single-lens reflex models. It is more accurately known as the M42 × 1 mm standard, which means that it is a metric screw thread of 42 mm diameter and 1 mm thread pitch.