给个英文的.个人理解可能会有点出入.基本上是这个意思. :u>RyKu|&R
b>ai"!
A candela plot is a plot of luminous intensity, or flux per solid angle. In photometric Na0^csPm
units, a luminous intensity plot is in units of candelas (lumens per steradian). In +_5*4>MC
radiometric units, an intensity plot is in units of watts per steradian. Candela plots [l}H:%O,
are commonly used in the design of illumination systems, especially those used in aU!}j'5Q
the far field. ;ku>_sG-
Candela data can be collected from ray sets of Missed rays, rays Exiting a surface Q((&Q?Vi
or rays Incident on a surface. Missed rays are a collection of all rays that “leave” x~e._k=
the model and “go off to infinity.” Exiting rays are the collection of ray segments n7t}G'*Y!^
following the intersection point of a ray at a surface. Due to ray splitting, several qG9a!sj
ray segments may contribute to the candela data for each incident ray. Incident 7^gO>2~
rays are the collection of ray segments which intersect the selected surface. No )U&9d
surface selection is required for Missed rays but one is necessary for Exiting and %e
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Incident rays. pN9 !
The candela plots represent flux versus angle and can be smoothed using the y``\^F
Candela Options dialog box. The iso-candela plots can be presented as false ,^/Wv!uPE
color maps or contour plots. The distribution plots are graphs of cross-sectional ..N6]u
curves through the candela distribution. Y{}
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The orientation of the candela plots is determined by the Normal Vector and the #(^<qr
Up Vector, as specified in the Analysis|Candela Options dialog box. The `B%%2p&
normal vector specifies the axis of the candela plot and the up vector specifies Mu3G/|t(
“which way is up.”