What do you do with a light saber that you don't do with a sword? It can cut through armor but if their wearing armor it is a full out war in which case they are using missile weapons. For mayhem a regular sword is better as it has a non-lethal option simply by using the flat.
So, what I'd like to suggest is that we brainstorm what properties a Lightsaber must have, based on what we know from the Star Wars films. I'm sure there's some contradictory information within that universe, so let's look to give an account of what properties a lightsaber must have in order to 1) block laser-shots and other lightsabers as well as 2) cut through just about anything in the manner in which it does, akin to a welding torch, and 3) have a fixed height which is triggered by turning it on, 4) all contained within the portable blade-hilt. Let's ignore the fictional tech-specs of lightsabers, such as the crystals and whatnot, and first just try and figure out what the heck must be happening.
Edited by rthomas2
My guess goes like this: The saber is a laser within an electromagnetic field. Laser weapons in fact fire miniature self-contained electromagnetic fields which trap lasers, and thus they're blocked by the repulsion of the fields. In the same manner, the fields of two sabers rebound against each other; this would mean that the fields of all laser weapons have the same charge. The laser provides the cutting force; somehow the laser extends just beyond the field; in fact, perhaps the laser emanates from outside the field, and is attracted by it so strongly that it covers the field. This would mean that the field is the center of the laser column, and the laser is an electron-thick coating of this center. The only real problem, apart from how this would be managed, is what stops the hilt from being cut open when the blade activates. The end of the hilt would have to somehow be protected. In that case, the field has its base at the top of the hilt, and is emanated in such a way as to block the laser from sliding down the hilt; of course this is not present in the laser shots.
I cut the wicked laser example entirely. Not only is it wildly irresponsible (even with the disclaimer below), but it flat out doesn't fit this trope.
Save for the 'laser' part, those aren't in any respect a laser sword. They're just a plain, ordinary laser, albeit an unusually powerful one for hobbyists.