etendue

集光率

发音

UK /ˌeɪ.tɒnˈd(j)uː/
其它
US /ˌeɪ.tɑnˈdu/

别名

étendue

释义与例句

n.
  1. 1.

    A conserved property of the light in an optical system which characterizes how "spread out" the light is in terms of angle and area: it is the product of its cross-sectional area (normal to the direction of propagation) and the solid angle it subtends.

    不可数 工程 物理

词源

Borrowed from French étendue (“area, expanse; size; extent, range, scale”), short for étendue géométrique (“geometric extent”).

来源：wiktionary