Question

Explom Aklanatic point​

Answer 1

Two points that on the axis of an optical system have the property that rays proceeding from one of them will all converge to, or seem to diverge from, the other if the rays fulfill the Abbe sine condition. The two foci of an ellipsoid of revolution are an example of aplanatic points.

Answer 2

Answer:

Two points that on the axis of an optical system have the property that rays proceeding from one of them will all converge to, or seem to diverge from, the other if the rays fulfill the Abbe sine condition. The two foci of an ellipsoid of revolution are an example of aplanatic points.

An optical surface in which for every point on the surface, the sum of the optical distances to two fixed points in space has a constant value. The surface does not contribute spherical aberration, coma or astigmatism to the image. ...