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?
He was without doubt the most inquisitive human I have ever met. His insatiable curiosity was not limited or distracted by his knowledge or expertise, nor was it casual or passive. It was ferocious, energetic and restless. His curiosity was practiced with intention and rigor.
Many of us have an innate predisposition to be curious. I believe that after a traditional education, or working in an environment with many people, curiosity is a decision requiring intent and discipline.
In larger groups our conversations gravitate towards the tangible, the measurable. It is more comfortable, far easier and more socially acceptable talking about what is known. Being curious and exploring tentative ideas were far more important to Steve than being socially acceptable.
Our curiosity begs that we learn. And for Steve, wanting to learn was far more important than wanting to be right.