给个英文的.个人理解可能会有点出入.基本上是这个意思. $gsn@P>"
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A candela plot is a plot of luminous intensity, or flux per solid angle. In photometric ipB*]B F[
units, a luminous intensity plot is in units of candelas (lumens per steradian). In r>N5 ^
radiometric units, an intensity plot is in units of watts per steradian. Candela plots ;m{*iKL6{
are commonly used in the design of illumination systems, especially those used in =;.#Bds
the far field. rA9BY :N@
Candela data can be collected from ray sets of Missed rays, rays Exiting a surface YYDLFt r2
or rays Incident on a surface. Missed rays are a collection of all rays that “leave” {K-]n h/
the model and “go off to infinity.” Exiting rays are the collection of ray segments k~ #F@_
following the intersection point of a ray at a surface. Due to ray splitting, several GWZ0!V
ray segments may contribute to the candela data for each incident ray. Incident \S(:O8_"68
rays are the collection of ray segments which intersect the selected surface. No k,>sBk 8
surface selection is required for Missed rays but one is necessary for Exiting and ,bRvj 8"M
Incident rays. 7dl]f#uZU
The candela plots represent flux versus angle and can be smoothed using the @`<v d@
Candela Options dialog box. The iso-candela plots can be presented as false 4e d+'-"m
color maps or contour plots. The distribution plots are graphs of cross-sectional y0vo-)E]-]
curves through the candela distribution. 0Y# S2ty
The orientation of the candela plots is determined by the Normal Vector and the *S.R#4w
Up Vector, as specified in the Analysis|Candela Options dialog box. The * iW>i^
normal vector specifies the axis of the candela plot and the up vector specifies gTRm
“which way is up.”
