| 释义 |
〔steradian〕A unit of measure equal to the solid angle subtended at the center of a sphere by an area on the surface of the sphere that is equal to the radius squared:立体弧度:由球心所张成的立体角,它在球面上所截取平面的面积等于以球半径为边长的正方形面积:〔steradian〕The total solid angle of a sphere is 4π steradians. See table at measurement 球的立体角和为4π立体弧度 参见 measurement |