给个英文的.个人理解可能会有点出入.基本上是这个意思. ex=) H%_|
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A candela plot is a plot of luminous intensity, or flux per solid angle. In photometric gE1|lY$NL
units, a luminous intensity plot is in units of candelas (lumens per steradian). In &|NZ8:*+#
radiometric units, an intensity plot is in units of watts per steradian. Candela plots Md?acWE*L
are commonly used in the design of illumination systems, especially those used in Seg#s.
the far field. bZK+9IR
Candela data can be collected from ray sets of Missed rays, rays Exiting a surface HoV{U zm
or rays Incident on a surface. Missed rays are a collection of all rays that “leave” ]*a@*0=
the model and “go off to infinity.” Exiting rays are the collection of ray segments cp| :8 [
following the intersection point of a ray at a surface. Due to ray splitting, several o[n<M> @
ray segments may contribute to the candela data for each incident ray. Incident * F|i&2
rays are the collection of ray segments which intersect the selected surface. No /t$*W\PL@
surface selection is required for Missed rays but one is necessary for Exiting and q$|0)}
Incident rays. >^ ;(c4C
The candela plots represent flux versus angle and can be smoothed using the (<
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Candela Options dialog box. The iso-candela plots can be presented as false yW{mK
color maps or contour plots. The distribution plots are graphs of cross-sectional h&q=I.3O|?
curves through the candela distribution. +*: }p
The orientation of the candela plots is determined by the Normal Vector and the YK7 \D:
Up Vector, as specified in the Analysis|Candela Options dialog box. The f@h2;An$w
normal vector specifies the axis of the candela plot and the up vector specifies 48:liR
“which way is up.”
