给个英文的.个人理解可能会有点出入.基本上是这个意思. URsx>yx _?c.m*)A A candela plot is a plot of luminous intensity, or flux per solid angle. In photometric Q|(}rIWOQA units, a luminous intensity plot is in units of candelas (lumens per steradian). In 1sqE/-v1_^ radiometric units, an intensity plot is in units of watts per steradian. Candela plots C%o|}i v" are commonly used in the design of illumination systems, especially those used in 1q}LO2 the far field. ")Fd'&58 Candela data can be collected from ray sets of Missed rays, rays Exiting a surface >. |({;n9 or rays Incident on a surface. Missed rays are a collection of all rays that “leave” PIri|ZS the model and “go off to infinity.” Exiting rays are the collection of ray segments V?{d<Ng~J following the intersection point of a ray at a surface. Due to ray splitting, several -b-a21,m> ray segments may contribute to the candela data for each incident ray. Incident J>Ar(p rays are the collection of ray segments which intersect the selected surface. No AFAg3/ surface selection is required for Missed rays but one is necessary for Exiting and M)bQvjj Incident rays. \dk1a The candela plots represent flux versus angle and can be smoothed using the YdhTjvx Candela Options dialog box. The iso-candela plots can be presented as false hi8q?4jE color maps or contour plots. The distribution plots are graphs of cross-sectional >XgoN\w curves through the candela distribution. u[GZ~L The orientation of the candela plots is determined by the Normal Vector and the ]rG=\>U3~ Up Vector, as specified in the Analysis|Candela Options dialog box. The WyO*8b_
D normal vector specifies the axis of the candela plot and the up vector specifies qezWfR` “which way is up.”