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A candela plot is a plot of luminous intensity, or flux per solid angle. In photometric IzI2w6a
units, a luminous intensity plot is in units of candelas (lumens per steradian). In $<da<}b
radiometric units, an intensity plot is in units of watts per steradian. Candela plots KD* xFap
are commonly used in the design of illumination systems, especially those used in L/c`t7
the far field. roM!%hb
Candela data can be collected from ray sets of Missed rays, rays Exiting a surface HT%'dZ1
or rays Incident on a surface. Missed rays are a collection of all rays that “leave” csjCXT=Ve
the model and “go off to infinity.” Exiting rays are the collection of ray segments
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following the intersection point of a ray at a surface. Due to ray splitting, several 7R7e3p,K
ray segments may contribute to the candela data for each incident ray. Incident y2M]z:Y U
rays are the collection of ray segments which intersect the selected surface. No up!54}qy
surface selection is required for Missed rays but one is necessary for Exiting and -T=sY/O
Incident rays. [pxC3{|d$
The candela plots represent flux versus angle and can be smoothed using the N8KH.P+
Candela Options dialog box. The iso-candela plots can be presented as false 6Z#$(oC
color maps or contour plots. The distribution plots are graphs of cross-sectional %7hf6Xo=
curves through the candela distribution. ^xX1G_{
The orientation of the candela plots is determined by the Normal Vector and the )}$]~
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Up Vector, as specified in the Analysis|Candela Options dialog box. The 2|A?9aE%0
normal vector specifies the axis of the candela plot and the up vector specifies Qf($F,)K
“which way is up.”