Akai is right!!
Akai has found the easiest way to defeat him. I tried all the methods on this post, and his is the easiest. Just remember to swing the your saber at the shield when he pauses in his firing. Just holding the saber on the sheild does not work. After the sheild goes down, just start swinging away. It helps if you use a strafe/swing method. That way you never stop moving, and he can't take a swing at you.
Thanks Akai! It took me more than a dozen tries using the other methods, (all of them failing), before I tried yours. The first time I used your method, it worked like a charm.