给个英文的.个人理解可能会有点出入.基本上是这个意思. v#*9rNEj0
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A candela plot is a plot of luminous intensity, or flux per solid angle. In photometric =ic"K6mhq
units, a luminous intensity plot is in units of candelas (lumens per steradian). In D QO~<E6c
radiometric units, an intensity plot is in units of watts per steradian. Candela plots Dyv 6K_,
are commonly used in the design of illumination systems, especially those used in Cj31>k1
the far field. : l>&5w;
Candela data can be collected from ray sets of Missed rays, rays Exiting a surface N*z_rZE
or rays Incident on a surface. Missed rays are a collection of all rays that “leave” $;NxO0$
the model and “go off to infinity.” Exiting rays are the collection of ray segments xc)A`(g
following the intersection point of a ray at a surface. Due to ray splitting, several [uCW8:e
ray segments may contribute to the candela data for each incident ray. Incident K] ;`
rays are the collection of ray segments which intersect the selected surface. No (sLFJ
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surface selection is required for Missed rays but one is necessary for Exiting and ^ FNvVbK|`
Incident rays. \GYh"5
The candela plots represent flux versus angle and can be smoothed using the g a|RW0
Candela Options dialog box. The iso-candela plots can be presented as false \jL n5$OW
color maps or contour plots. The distribution plots are graphs of cross-sectional L rV`P)$T
curves through the candela distribution. rT$J0"*=
The orientation of the candela plots is determined by the Normal Vector and the 4_qd5K+n"
Up Vector, as specified in the Analysis|Candela Options dialog box. The *,qW9z
normal vector specifies the axis of the candela plot and the up vector specifies `Wq4k>J}*
“which way is up.”