Detailed Explanations
The cardinal points lie on the optical axis of the optical system. Each point is defined by the effect the optical system has on rays that pass through that point, in the paraxial approximation. The paraxial approximation assumes that rays travel at shallow angles with respect to the optical axis, so that and . Aperture effects are ignored: rays that do not pass through the aperture stop of the system are not considered in the discussion below.
Read more about this topic: Cardinal Point (optics)
Famous quotes containing the words detailed and/or explanations:
“[The Republicans] offer ... a detailed agenda for national renewal.... [On] reducing illegitimacy ... the state will use ... funds for programs to reduce out-of-wedlock pregnancies, to promote adoption, to establish and operate children’s group homes, to establish and operate residential group homes for unwed mothers, or for any purpose the state deems appropriate. None of the taxpayer funds may be used for abortion services or abortion counseling.”
—Newt Gingrich (b. 1943)
“Financiers are great mythomaniacs, their explanations and superstitions are those of primitive men; the world is a jungle to them. They perceive acutely that they are at the dawn of economic history.”
—Christina Stead (1902–1983)