Thread by @benridout

Did #Disney invent a real working #lightsaber?

Yes they did.

It won't melt through metal blast doors, or cut off your hand, but it does feature an illuminated blade that will extend and retract at the push of a button.

This animation shows the concept behind the tech.

At a recent virtual press conference, Disney Parks chairman Josh D'amaro briefly revealed what onlookers have called a "real" lightsaber.

After studying the patent (see image), here's how it seems to work...

It's based on a familiar concept - the Tape Measure. A steel tape measure is somewhat sturdy when extended short distances. The curve in the steel provides strength and the mostly flat tape can still be wound up on a reel inside the body of the tape measure. That's important.

Disney's lightsaber design extends (get it?) the basic tape measure design. Imagine connecting two tape measures together so each tape faces in on each other when they are extended. Connect the ends of the tapes with a circular cap.

Next, widen the tapes and increase the curve, allowing them to partially wrap around each other and form a complete cylinder. Drive this system with a motor so both reels can be extended and retracted in synch at the push of a button. Now, you've got a lightsaber!

With the two blades wrapped around each other, each forming slightly more than a semi-circle, you've got a cylindrical "blade". In Disney's design, the tape/blade material is a semi-transparent flexible plastic.

It can be deformed into-a semi-circle when the tape is extended, but it can be rolled flat when it is wound on the spool. Imagine cutting a paper towel cardboard cylinder along its length. You can flatten it, but it will spring back to its round shape. Same idea.

The cap at the end of the blade maintains the curved profiles at the top of the blade, a guide form at the top of the hilt maintains the curved profile as each tape exits the hilt.

The blade material also serves to diffuse the light, which is provided by a strand of flexible LED tape. The LEDs are contained inside the hilt on a 3rd spool. The LEDs are attached to the end cap so they can be pulled up when the blade extends.

As the blade extends, the LEDs unwind off their spool and are pulled up inside the hollow core of the blade providing internal illumination.

The hilt holds the 3 spools (2 for the blade tapes and 1 for the LEDs), a small motor driven system that powers the extension/retraction, a battery, and the electronics to make it all work.

Don’t be fooled by the slow animation.

The patent claims the blade will fully extend (24+ inches) in less than 1 second.

Blade diameter is constrained by the hilt size, but said to be 0.5-2 inches wide with no taper (parallel sides).