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The front doublet is air-gapped and divergent; the rear doublet is glued and convergent. This arrangement was better at correcting spherical and chromatic aberrations and astigmatism than previous lens designs. In optics, a doublet is a type of lens made up of two simple lenses paired together. Such an arrangement allows more optical surfaces ...
This list covers optical lens designs grouped by tasks or overall type. The field of optical lens designing has many variables including the function the lens or group of lenses have to perform, the limits of optical glass because of the index of refraction and dispersion properties, and design constraints including realistic lens element center and edge thicknesses, minimum and maximum air ...
Cooke triplet. According to Taylor, the lens design was derived by considering a cemented achromatic doublet consisting of one thin negative element and one thin positive element, both of equal power; such a doublet would result in a compound lens with zero net power but also a flat field of focus.
A doublet lens has four surfaces with radii R 1 through R 2. Surfaces with positive radii curve away from the object (R 1 positive is a convex first surface); negative radii curve toward the object (R 1 negative is a concave first surface). The descriptions of the achromat lens designs mention advantages of designs that do not produce "ghost ...
The original two element Gauss was a telescope objective lens consisting of closely spaced positive and negative menisci, invented in 1817 by Carl Friedrich Gauss as an improvement to the Fraunhofer Achromatic telescope objective lens by adding a meniscus lens to its single convex and concave lens design.
The Rodenstock Imagon is an achromat doublet photographic lens design uncorrected for spherical aberration used together with diffusion discs ("sink strainers") called sieve aperture (Siebblende in German). The lens is one of the classic professional soft-focus "portrait lenses".
An Achromatic telescope uses an achromatic lens to correct for this. An achromatic lens is a compound lenses made with two types of glass with different dispersion. One element, a concave lens made out of Flint glass, has relatively high dispersion, while the other, a convex element made of Crown glass, has a lower dispersion. The crown lens is ...
There are many types of dialyte camera lenses. One popular design is perfectly symmetric, which provides good correction for many aberrations.This consists of two air-spaced achromatic doublets arranged back-to-back around a central stop, or four air spaced lens elements in total: the outer pair is biconvex and the inner pair is biconcave; one example is the Celor.