Search results
Results from the WOW.Com Content Network
Permission is granted to copy, distribute and/or modify this document under the terms of the GNU Free Documentation License, Version 1.2 or any later version published by the Free Software Foundation; with no Invariant Sections, no Front-Cover Texts, and no Back-Cover Texts.
English: Ray diagram of an imperfect convex lens L, showing the circle of confusion (C). In a perfect lens, light rays entering the lens parallel to the axis pass through a single point, the focal point. However, if the lens has flaws or aberrations, the rays don't pass through a single point.
English: Ray diagram of a convex lens focusing light rays. In a flawless convex lens L with no aberrations all the light rays entering the lens parallel to the axis will converge to a point, the focal point F. Due to diffraction the light at F isn't actually concentrated in a point but occupies a finite sized spot.
A lens contained between two circular arcs of radius R, and centers at O 1 and O 2. In 2-dimensional geometry, a lens is a convex region bounded by two circular arcs joined to each other at their endpoints. In order for this shape to be convex, both arcs must bow outwards (convex-convex). This shape can be formed as the intersection of two ...
An extended hemispherical lens is a special type of plano-convex lens, in which the lens's curved surface is a full hemisphere and the lens is much thicker than the radius of curvature. Another extreme case of a thick convex lens is a ball lens, whose shape is completely round. When used in novelty photography it is often called a "lensball".
An axicon is a specialized type of lens that has a conical surface. An axicon transforms a laser beam into a ring shaped distribution. [1] They can be convex or concave and be made of any optical material. The combination with other axicons or lenses allows a wide variety of beam patterns to be generated.
Main page; Contents; Current events; Random article; About Wikipedia; Contact us; Pages for logged out editors learn more
English: Meniscus lenses have one concave surface (illustrated here on the right side) and one convex surface (illustrated here on the left side). The positive (converging) meniscus lens has a thicker center than edge, and represents the case where the convex surface (shown in green) has a smaller radius than the concave surface (shown in red).