给个英文的.个人理解可能会有点出入.基本上是这个意思. +dh]k=6
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A candela plot is a plot of luminous intensity, or flux per solid angle. In photometric R uk6+U
units, a luminous intensity plot is in units of candelas (lumens per steradian). In ~0 FqY &4
radiometric units, an intensity plot is in units of watts per steradian. Candela plots 9Jk(ID'c
are commonly used in the design of illumination systems, especially those used in y~S[0]y>
the far field. *} w.xt
Candela data can be collected from ray sets of Missed rays, rays Exiting a surface {@ ,
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or rays Incident on a surface. Missed rays are a collection of all rays that “leave” i y: ;g
the model and “go off to infinity.” Exiting rays are the collection of ray segments kx UGd)S
following the intersection point of a ray at a surface. Due to ray splitting, several ,.}PZL
ray segments may contribute to the candela data for each incident ray. Incident IW BVfN->}
rays are the collection of ray segments which intersect the selected surface. No >LU*F|F]B
surface selection is required for Missed rays but one is necessary for Exiting and _Wb-&6{
Incident rays. Mc6Cte]3|
The candela plots represent flux versus angle and can be smoothed using the Iwn@%?7
Candela Options dialog box. The iso-candela plots can be presented as false 0`ib_&yI
color maps or contour plots. The distribution plots are graphs of cross-sectional aQ~x$T|
curves through the candela distribution. b]g.>$[nX
The orientation of the candela plots is determined by the Normal Vector and the v}Aw!D v /
Up Vector, as specified in the Analysis|Candela Options dialog box. The Zz3#Kt5t3
normal vector specifies the axis of the candela plot and the up vector specifies t=e0z^2i+
“which way is up.”
