Just some ideas out of my head. Use lattice on the cylinder, select the lattice point on on end and create a cluster, then do the same on the other end. Finally apply the motion path to one of the clusters. You can even make the cylinder as softbody for better looking motion!
But... why do you just using "lightning" to create it?
first, thank you for your reply
may i try yr method then reply again
i search websites for animate laser beam this two nights
found below linked method
http://forums.cgsociety.org/archive/index.php/t-260897.html wonder which real method is better?
Wo, stantang Thank you very much
I found yr method suit my requirements
however still need to reduce the divisions to 2 ( one head and tail)aviod the laser to be break
Finally,
I only use the glow material for cylinder pretending laser but not lightning
u got any idea?
Lightning is a quick setup for creating laser effects, not a shader. Just create two locators, put them away from each other select them, and use dynamics-->effects-->lightning. You use see what I mean.