the Rodenstock contact lens consist of corneal contact lenses and high-powered, spherical condensing lenses . A real, inverted image of the fundus is formed within the spherical glass element, which is within the focal range of the slit-lamp biomicroscope. Because the condensing lens is so close to the eye and has such a high power, the field of view is very wide. This makes these lenses especially suited for a wide-angle view of the posterior pole and midperipheral fundus.
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