01274nas a2200265   4500000000100000000000100001008004100002653001300043653002400056653003600080653002500116653001500141100002100156700001500177700002600192700002300218700002000241700002200261700002700283245005800310856007100368300001200439490000700451520055000458       2010                            d10aanidolic10aforward ray tracing10anon-imaging daylight collectors10aperformance criteria10aphotometry1 aStephen Wittkopf1 aLars Grobe1 aDavid Geisler-Moroder1 aRaphaël Compagnon1 aJérôme Kämpf1 aFriedrich Linhart1 aJean-Louis Scartezzini00aRay tracing study for non-imaging daylight collectors  uhttp://www.sciencedirect.com/science/article/pii/S0038092X1000112X  a986-9960 v843 aThis paper presents a novel method to study how well non-imaging daylight collectors pipe diffuse daylight into long horizontal funnels for illuminating deep buildings. Forward ray tracing is used to derive luminous intensity distributions curves (LIDC) of such collectors centered in an arc-shaped light source representing daylight. New photometric characteristics such as 2D flux, angular spread and horizontal offset are introduced as a function of such LIDC. They are applied for quantifying and thus comparing different collector contours.