angular divergence
1Beam divergence — The beam divergence of an electromagnetic beam is an angular measure of the increase in beam diameter with distance from the optical aperture or antenna aperture from which the electromagnetic beam emerges. The term is relevant only in the far… …
2optics — /op tiks/, n. (used with a sing. v.) the branch of physical science that deals with the properties and phenomena of both visible and invisible light and with vision. [1605 15; < ML optica < Gk optiká, n. use of neut. pl. of OPTIKÓS; see OPTIC,… …
3Alternate — Al*ter nate (?; 277), a. [L. alternatus, p. p. of alternate, fr. alternus. See {Altern}, {Alter}.] 1. Being or succeeding by turns; one following the other in succession of time or place; by turns first one and then the other; hence, reciprocal.… …
4Alternate alligation — Alternate Al*ter nate (?; 277), a. [L. alternatus, p. p. of alternate, fr. alternus. See {Altern}, {Alter}.] 1. Being or succeeding by turns; one following the other in succession of time or place; by turns first one and then the other; hence,… …
5Alternate angles — Alternate Al*ter nate (?; 277), a. [L. alternatus, p. p. of alternate, fr. alternus. See {Altern}, {Alter}.] 1. Being or succeeding by turns; one following the other in succession of time or place; by turns first one and then the other; hence,… …
6Alternate generation — Alternate Al*ter nate (?; 277), a. [L. alternatus, p. p. of alternate, fr. alternus. See {Altern}, {Alter}.] 1. Being or succeeding by turns; one following the other in succession of time or place; by turns first one and then the other; hence,… …
7physical science, principles of — Introduction the procedures and concepts employed by those who study the inorganic world. physical science, like all the natural sciences, is concerned with describing and relating to one another those experiences of the surrounding… …
8Gaussian beam — In optics, a Gaussian beam is a beam of electromagnetic radiation whose transverse electric field and intensity (irradiance) distributions are well approximated by Gaussian functions. Many lasers emit beams that approximate a Gaussian profile, in …
9Electromagnetic wave equation — The electromagnetic wave equation is a second order partial differential equation that describes the propagation of electromagnetic waves through a medium or in a vacuum. The homogeneous form of the equation, written in terms of either the… …
10Curvilinear coordinates — Curvilinear, affine, and Cartesian coordinates in two dimensional space Curvilinear coordinates are a coordinate system for Euclidean space in which the coordinate lines may be curved. These coordinates may be derived from a set of Cartesian… …
