Stilb (unit) Stilb (unit) The stilb (sb) is the CGS unit of luminance for objects that are not self-luminous. It is equal to one candela per square centimeter or 10 nits (candelas per square meter). The name was coined by the French physicist André Blondel around 1920. It comes from the Greek word "stilbein" meaning "to glitter". It was in common use in Europe up to World War I. In North America self-explanatory terms such as candle per square inch and candle per square meter were more common. The unit has since largely been replaced by the SI unit: candela per square
Borel measure Borel measure In mathematics, specifically in measure theory, a Borel measure on a topological space is a measure that is defined on all open sets (and thus on all Borel sets). Some authors require additional restrictions on the measure, as described below. Let formula_1 be a locally compact Hausdorff space, and let formula_2 be the smallest σ-algebra that contains the open sets of formula_1; this is known as the σ-algebra of Borel sets. A Borel measure is any measure formula_4 defined on the σ-algebra of Borel sets. Some authors require in addition that formula_4 is locally compact, meaning that formula_6