Editing Orthographic projection (section)

{{Short description|Means of projecting three-dimensional objects in two dimensions}}
{{For multi|the orthographic projection as a map projection|Orthographic map projection|mathematical discussion in terms of linear algebra|Projection (linear algebra)}}

{{Views}}

'''Orthographic projection''' (also '''orthogonal projection''' and '''analemma'''){{efn|This usage is obsolete; the common meaning of "[[analemma]]" is a diagram of the position of the Sun from the Earth.<ref>Sawyer, F., [http://citeseerx.ist.psu.edu/viewdoc/download?doi=10.1.1.142.3875&rep=rep1&type=pdf Of Analemmas, Mean Time and the Analemmatic Sundial]</ref>}} is a means of representing [[Three-dimensional space|three-dimensional]] objects in [[Plane (mathematics)|two dimensions]]. Orthographic projection is a form of [[parallel projection]] in which all the projection lines are [[orthogonal]] to the [[projection plane]],<ref name="maynard">{{Cite book | last = Maynard | first = Patric | title = Drawing Distinctions: The Varieties of Graphic Expression | publisher = Cornell University Press | year = 2005 | pages = 22 | url = https://books.google.com/books?id=4Y_YqOlXoxMC&q=axonometric%20orthographic&pg=PA22 | isbn = 0-8014-7280-6}}</ref> resulting in every plane of the scene appearing in [[affine transformation]] on the viewing surface. The obverse of an orthographic projection is an [[oblique projection]], which is a parallel projection in which the projection lines are ''not'' orthogonal to the projection plane.

The term ''orthographic'' sometimes means a technique in [[multiview projection]] in which principal axes or the planes of the subject are also parallel with the projection plane to create the ''primary views''.<ref name="maynard"/>  If the principal planes or axes of an object in an orthographic projection are ''not'' parallel with the projection plane, the depiction is called ''axonometric'' or an ''auxiliary views''. (''Axonometric projection'' is synonymous with ''parallel projection''.) Sub-types of ''primary views'' include ''plans'', ''elevations'', and ''sections''; sub-types of ''auxiliary views'' include ''isometric'', ''dimetric'', and ''trimetric projections''. 

A lens that provides an orthographic projection is an [[Telecentric lens#Object-space telecentric lenses|object-space telecentric lens]].