给个英文的.个人理解可能会有点出入.基本上是这个意思. ZXPX,~ 5o FW DNpr A candela plot is a plot of luminous intensity, or flux per solid angle. In photometric _Y m2/3! units, a luminous intensity plot is in units of candelas (lumens per steradian). In Bk{]g=DO radiometric units, an intensity plot is in units of watts per steradian. Candela plots P16~Qj are commonly used in the design of illumination systems, especially those used in :\_ 5oVb the far field. &mM0AA'\?H Candela data can be collected from ray sets of Missed rays, rays Exiting a surface Y8t8!{ytg or rays Incident on a surface. Missed rays are a collection of all rays that “leave” 8zq=N#x the model and “go off to infinity.” Exiting rays are the collection of ray segments ChQxa following the intersection point of a ray at a surface. Due to ray splitting, several @IZnFHN ray segments may contribute to the candela data for each incident ray. Incident u: rays are the collection of ray segments which intersect the selected surface. No 1Ai^cf:S surface selection is required for Missed rays but one is necessary for Exiting and >=w)x,0yX Incident rays. p5*jzQ The candela plots represent flux versus angle and can be smoothed using the 8H`[*|{' Candela Options dialog box. The iso-candela plots can be presented as false jSaU?ac color maps or contour plots. The distribution plots are graphs of cross-sectional G^@5H/) curves through the candela distribution. oxtay7fx The orientation of the candela plots is determined by the Normal Vector and the ;5AcFB Up Vector, as specified in the Analysis|Candela Options dialog box. The )Q JUUn# normal vector specifies the axis of the candela plot and the up vector specifies 1=v*O.XW` “which way is up.”