给个英文的.个人理解可能会有点出入.基本上是这个意思. s ?5 d
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A candela plot is a plot of luminous intensity, or flux per solid angle. In photometric ` -yhl3si
units, a luminous intensity plot is in units of candelas (lumens per steradian). In ^b:Xo"q#H
radiometric units, an intensity plot is in units of watts per steradian. Candela plots V15q01bE#
are commonly used in the design of illumination systems, especially those used in >b 3@>W
the far field. Q^vGj</u
Candela data can be collected from ray sets of Missed rays, rays Exiting a surface ` v>/
or rays Incident on a surface. Missed rays are a collection of all rays that “leave” .$UTH@;7
the model and “go off to infinity.” Exiting rays are the collection of ray segments C1n? ?Y[
following the intersection point of a ray at a surface. Due to ray splitting, several e{:86C!d)
ray segments may contribute to the candela data for each incident ray. Incident S'|lU@P Cl
rays are the collection of ray segments which intersect the selected surface. No B U'Ki \
surface selection is required for Missed rays but one is necessary for Exiting and q $3HvZP
Incident rays. /%-o.hT
The candela plots represent flux versus angle and can be smoothed using the IC\E , m
Candela Options dialog box. The iso-candela plots can be presented as false +J% 6bn)U
color maps or contour plots. The distribution plots are graphs of cross-sectional o}d2N/T
curves through the candela distribution. " S ?Km
The orientation of the candela plots is determined by the Normal Vector and the f>|9 l
Up Vector, as specified in the Analysis|Candela Options dialog box. The ysL0 hwir
normal vector specifies the axis of the candela plot and the up vector specifies F{kG
“which way is up.”
