给个英文的.个人理解可能会有点出入.基本上是这个意思. IV1Y+Z ) 57 Bx- A candela plot is a plot of luminous intensity, or flux per solid angle. In photometric K]G(u"' units, a luminous intensity plot is in units of candelas (lumens per steradian). In ?u/UV,";y radiometric units, an intensity plot is in units of watts per steradian. Candela plots D.|r
[c are commonly used in the design of illumination systems, especially those used in qvK/} the far field. r|
)45@ Candela data can be collected from ray sets of Missed rays, rays Exiting a surface "v(pluN| or rays Incident on a surface. Missed rays are a collection of all rays that “leave” kFC*, the model and “go off to infinity.” Exiting rays are the collection of ray segments -sZb+2tDa following the intersection point of a ray at a surface. Due to ray splitting, several nMfR<%r ray segments may contribute to the candela data for each incident ray. Incident {
0&l*@c& rays are the collection of ray segments which intersect the selected surface. No ,<)D3K< surface selection is required for Missed rays but one is necessary for Exiting and j"aY\cLr t Incident rays. 0fn*;f8{XJ The candela plots represent flux versus angle and can be smoothed using the q-ko)] Candela Options dialog box. The iso-candela plots can be presented as false !c1M{klP color maps or contour plots. The distribution plots are graphs of cross-sectional F&m9G >r curves through the candela distribution. }f14# y; The orientation of the candela plots is determined by the Normal Vector and the dUt4]
ar Up Vector, as specified in the Analysis|Candela Options dialog box. The )0ydSz`B normal vector specifies the axis of the candela plot and the up vector specifies URg;e M# “which way is up.”