In optics, a caustic is the envelope of light rays reflected or refracted by a curved surface or object, or the projection of that envelope of rays on another surface. The caustic is a curve or surface to which each of the light rays is tangent, defining a boundary of an envelope of rays as a curve of concentrated light.
A piece of milled plexiglass acting as a projecting lens; via the Computer Graphics and Geometry Lab at the École Polytechnique Fédérale de Lausanne
New milling techniques applied to glass and plexiglass panels could be used to “create windows that are also cryptic projectors, summoning ghostly images from sunlight.”
[Pauly and Bompas] hope that the technique will be used in architectural design, to create windows that mould sunlight and throw images or patterns onto walls or floors,” which, if timed, milled, and manipulated just right, could produce a slowly animated sequence of images being projected by an otherwise empty window during different times of day.
To control the shape of a caustic pattern generated by a specular or refractive surface, we need to solve the inverse problem: how can we change the surface geometry, such that incident light is redirected to produce a desired caustic image?
Both a book and a MoMA exhibition of the same name by Bernard Rudofsky originally published in 1964. It provides a demonstration of the artistic, functional, and cultural richness of vernacular architecture.
In 200 enlarged black-and-white-photographs, he showed various kinds of architectures, landscapes, and people living with or within architectures. Shown without texts or explanations, the visitors were just confronted with imagery that showed indigenous building traditions, which were very much at odds with the ideas of architectural modernism which had been promoted through NYC MoMA's Philip Johnson in his famous 1932 exhibition "Modern Architecture. International Exhibition".