给个英文的.个人理解可能会有点出入.基本上是这个意思. feS$)H9-
RIUJX{?
A candela plot is a plot of luminous intensity, or flux per solid angle. In photometric [So1`IA6
units, a luminous intensity plot is in units of candelas (lumens per steradian). In Hr=|xw8.
radiometric units, an intensity plot is in units of watts per steradian. Candela plots G*_]Lz(N
are commonly used in the design of illumination systems, especially those used in 96;5
the far field. %hmRh~/&
Candela data can be collected from ray sets of Missed rays, rays Exiting a surface ]5@n`;&#.
or rays Incident on a surface. Missed rays are a collection of all rays that “leave” $;(@0UDE
the model and “go off to infinity.” Exiting rays are the collection of ray segments H;<>uE Lie
following the intersection point of a ray at a surface. Due to ray splitting, several QoUdTIIL
ray segments may contribute to the candela data for each incident ray. Incident e*`ht+
rays are the collection of ray segments which intersect the selected surface. No
PPy~dp
surface selection is required for Missed rays but one is necessary for Exiting and SHS fe{n
Incident rays. *@^@7`W
The candela plots represent flux versus angle and can be smoothed using the K 0 o F=|
Candela Options dialog box. The iso-candela plots can be presented as false 9%SC#V'
color maps or contour plots. The distribution plots are graphs of cross-sectional 78*8-
curves through the candela distribution. zICCSF&H
The orientation of the candela plots is determined by the Normal Vector and the =rZ'!Pa
Up Vector, as specified in the Analysis|Candela Options dialog box. The wA 7\K~fHV
normal vector specifies the axis of the candela plot and the up vector specifies +-),E.
“which way is up.”
