给个英文的.个人理解可能会有点出入.基本上是这个意思. zl0;84:H mG0L !5 A candela plot is a plot of luminous intensity, or flux per solid angle. In photometric ~RcNZ\2y units, a luminous intensity plot is in units of candelas (lumens per steradian). In ZrFr`L5F; radiometric units, an intensity plot is in units of watts per steradian. Candela plots ?g5iok { are commonly used in the design of illumination systems, especially those used in V]r hr the far field. L30>|g Candela data can be collected from ray sets of Missed rays, rays Exiting a surface :lgHL3yl or rays Incident on a surface. Missed rays are a collection of all rays that “leave” V@B7P{gH the model and “go off to infinity.” Exiting rays are the collection of ray segments 7*+Km'=M following the intersection point of a ray at a surface. Due to ray splitting, several !A~d[</]m ray segments may contribute to the candela data for each incident ray. Incident /rqqC(1 rays are the collection of ray segments which intersect the selected surface. No 3.(.*> surface selection is required for Missed rays but one is necessary for Exiting and E^7C
_JP Incident rays. 7 n\mj\ The candela plots represent flux versus angle and can be smoothed using the 9~=gwP Candela Options dialog box. The iso-candela plots can be presented as false zT$0xj8 color maps or contour plots. The distribution plots are graphs of cross-sectional Nfr:`$k curves through the candela distribution. ^SEc./$ The orientation of the candela plots is determined by the Normal Vector and the ~D*b3K8X Up Vector, as specified in the Analysis|Candela Options dialog box. The *U
M!( normal vector specifies the axis of the candela plot and the up vector specifies +e U`H[iu “which way is up.”