Reply To: Set up a holding company
The Focus Fusion Society › Forums › Story, Art, Song, Self Expression › Plasma sabers › Reply To: Set up a holding company
Ivy MattIf it does a good job of duplicating the look of the movie prop and special effect, presumably that would qualify as similar enough for marketing copy. There are other lightsabers out there that look closer to the “real thing”, and have more authentic sound effects as well. They are licensed by Lucasfilm, of course. The more expensive are only half the cost as well, but I don’t believe they have a real plasma “blade”.
The Real Thing
As for the Real Thing, there are somewhat conflicting ideas out there about how a lightsaber works. The Star Wars novelization doesn’t offer much except that it has switches on the handle, a metal disk above the handle that is polished to a mirror brightness, and that there are several small, jewellike components built into both the handle and disk, including a power cell with a surprisingly high energy rating. This is supposedly a description of the Skywalker lightsaber, but I wonder if Alan Dean Foster (Lucas’ ghost writer) was using that prop or the Obi-Wan lightsaber prop for reference.
Lasers
The Star Wars Technical Journal is cautiously terse as well, but gives a little more detail. The handle is “durasteel”, and it contains a power cell, faceted crystallite lenses, and a focusing core. The lightsaber blade is described as a “coherent beam” that bends back upon itself. This is consistent with the idea that the lightsaber blade is a laser beam, as are the frequent references to lightsaber crystals in Star Wars lore. (Also, the young Anakin refers to the lightsaber as a “laser sword”, but there’s no guarantee that the term used by a slave boy on Tatooine has any more scientific precision than the preferred, but more ambiguous term “lightsaber”.) The problem with lasers is that they go on for a lot more than a meter unless absorbed or reflected by a solid object. How a laser beam can be made to curve back on itself nearly 180° is a mystery to me. If I had to devise a concept, I’d say the lightsaber levitates a small mirror when activated, although I’m not sure how it would hold it in place.
“Energy”
I believe I’ve seen the lightsaber blade described as being composed of “pure energy”. According to my current understanding of physics, that is like saying something is composed of “pure movement”. Wookieepedia reaches a compromise by saying the lightsaber blade is composed of “pure plasma energy”.
Plasma
I think a meter-long plasma torch makes more sense than a laser beam, but it still has problems, as the torch will have trouble holding its shape in the lightest breeze, not to mention when it’s being swung about. Some sort of magnetic confinement may work, and Wookieepedia does mention that the lightsaber generates a “strong gyroscopic effect”. However, I have trouble seeing what magnetic geometry would allow the blade to be magnetically confined from the handle. Another possibility is that the lightsaber blade generates its own magnetic field like a Z-pinch device, but it’s still missing an electrode at the tip, and I think a vacuum tube would be necessary as well.
Wookieepedia’s compromise on the blade containment issue is that the plasma blade is confined by a “force containment field”, and that the field forces the blade to curve back on itself “to a negatively charged fissure ringing the emitter”. I’m not sure if that’s a Force containment field, but if it is it presumably doesn’t require operation by an able Force user, or Han Solo would have had a bit of trouble slicing that Tauntaun open.
Filaments?
Now, gradually getting back to reality, for some reason I’m starting to see some kind of a relationship between how the Star Wars lightsaber supposedly works and the plasma sheath produced in a plasma focus device. Of course, the curvature is not nearly as extreme as what you’d need for a lightsaber, but perhaps it’s a start.
More Realistic Schemes
Michio Kaku in Physics of the Impossible has his own idea for a lightsaber. His idea is that the lighsaber handle contains a narrow telescoping tube perforated with holes. When the lightsaber is activated the tube telescopes out and releases plasma through the holes.
Viewed from the present perspective, the lightsaber seems like an impractical weapon, as missile weapons have far outpaced advances in armor, and it doesn’t look like armor will ever get the advantage back. Should advances in armor increase the importance of melee weapons, however, there is a more practical design for a plasma sword, with the hilt and the flat of the blade being composed of solid material, and plasma forming only the cutting edge. The lightsaber has the advantage that its cutting edge is at all angles, although the plasma sword could perhaps be several blades intersecting along the axis to achieve the same advantage. The plasma sword, however, has the advantage that it pretty much already exists, albeit in a smaller form: the plasma scalpel.