Creating a Spline Mask/Mask Effect for a Spline Path

Hey Everyone,

I am trying to make the appearance of a laser coming down and bouncing off a surface. In the attached file, I created a single "V-shaped" path from a spline. Is there a way to mask this single path or is there a more efficient to make two spline paths and time them just right?

C4D File
http://f1.creativecow.net/7533/vshaped-path?uploaded=file

Thanks in Advance!