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Cardinal Points

Definition: a set of points which characterize the function of an optical element or a group of elements in Gaussian optics

German: Hauptpunkte

Category: general optics

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Various types of cardinal points are defined in Gaussian optics for characterizing the optical function of a single optical element or a group of such elements:

The cardinal points can be calculated from the ABCD matrix, and vice versa. They are useful, for example, when geometrically constructing images of objects.

According to the basic assumptions of Gaussian optics, the rays are considered for the limiting case of small angles against the optical axis. If parallel incoming rays are calculated for a wider range of offsets, for example, will generally not exactly meet in a focal point.

See also: Gaussian optics, focal points and focal planes, principal points and principal planes, nodal points
and other articles in the category general optics


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