Lightlike Rectilinear Congruence in Three Dimensional Minkowski Space 三维Minkowski空间中的类光线汇
Finally, we discuss the main surface of the lightlike rectilinear congruence, and prove what condition should be satisfied by the lightlike rectilinear congruence when B-scroll is just main surface. 最后,讨论类光线汇的主要曲面,且证明了B-scroll恰好为主要曲面时线汇需要满足的条件。