A prismatic surface is a surface generated by all the lines that are parallel to a given line and intersect a broken line that is not in the same plane as the given line. The broken line is the directrix of the surface; the parallel lines are its generators (or elements). If the broken line is closed (i.e. a closed polygon), then the surface is a closed prismatic surface.
With regards to crystallography, a prismatic surface is a single face of a prismatic form, which is an open form consisting of three, four, or six identical faces related by a symmetry operator.
Famous quotes containing the words prismatic and/or surface:
“Then a small rainbow like a trellis gate,
A very small moon-made prismatic bow,
Stood closely over us through which to go.”
—Robert Frost (1874–1963)
“All forms of beauty, like all possible phenomena, contain an element of the eternal and an element of the transitory—of the absolute and of the particular. Absolute and eternal beauty does not exist, or rather it is only an abstraction creamed from the general surface of different beauties. The particular element in each manifestation comes from the emotions: and just as we have our own particular emotions, so we have our own beauty.”
—Charles Baudelaire (1821–1867)