给个英文的.个人理解可能会有点出入.基本上是这个意思. za{z2# aJ
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A candela plot is a plot of luminous intensity, or flux per solid angle. In photometric .Y B}w
units, a luminous intensity plot is in units of candelas (lumens per steradian). In g3[Zh=+]E
radiometric units, an intensity plot is in units of watts per steradian. Candela plots ,M@LtA3g
are commonly used in the design of illumination systems, especially those used in lR] z8 &
the far field. "JI FF_
Candela data can be collected from ray sets of Missed rays, rays Exiting a surface q;co53.+P)
or rays Incident on a surface. Missed rays are a collection of all rays that “leave” =2&/Cn4
the model and “go off to infinity.” Exiting rays are the collection of ray segments yU * upQ
following the intersection point of a ray at a surface. Due to ray splitting, several |GPR3%9
ray segments may contribute to the candela data for each incident ray. Incident QP/6N9/
rays are the collection of ray segments which intersect the selected surface. No : B(F ?9qK
surface selection is required for Missed rays but one is necessary for Exiting and I,4t;4;Zk
Incident rays. u 6&<Bv
The candela plots represent flux versus angle and can be smoothed using the 8\,|T2w,X
Candela Options dialog box. The iso-candela plots can be presented as false !<9sOvka{
color maps or contour plots. The distribution plots are graphs of cross-sectional 1 o< l;:
curves through the candela distribution. CNwYQe-i
The orientation of the candela plots is determined by the Normal Vector and the ,Qvclu8r
Up Vector, as specified in the Analysis|Candela Options dialog box. The -dX{ R_*
normal vector specifies the axis of the candela plot and the up vector specifies scmn-4j'{
“which way is up.”
