[5] KongLB,Cheung C F,Jiang J B,et al. Characterization of free form optics in automotive lighting systems using an Optical-Geometrical Feature Base Method[J]. Optik,2011,122(4):358-363.
[8] Yang B,Wang Y T. Efficient ray-tracing for free-form re.flectors[J]. Optik,2009,120(1):40-44.