Star Wars has taken over the galaxy, the box office, and the toy aisles. With regular movie installments planned over the next several years and more series appearing on streaming platforms – there seems to be no end in sight to the universe of Star Wars. So get out your lightsabers, and let’s measure the lasers in these laser swords.
“This is the weapon of a Jedi Knight. Not as clumsy or random as a blaster. An elegant weapon, for a more civilized age.” – Obi-Wan Kenobi, A New Hope, 1977
Unless you’ve been living in the Outer Rim, you know that a Jedi’s weapon is a lightsaber, also known as a laser sword. Good guys tend to have green (Luke Skywalker), blue (Obi-Wan Kenobi), and occasionally other colors like purple, while those who associate with the “Dark Side” of the force have red lightsabers (Darth Vader).
| Lightsaber Color | Wielded by… | Meaning |
| Green | Luke Skywalker | Peace through force, when necessary |
| Blue | Obi-Wan Kenobi | Justice and protection |
| Purple | Mace Windu | Moral ambiguity |
| White | Ahsoka Tano | Calm and clear |
| Red | Darth Vader, and most Sith |
Evil and power |
| Yellow | Jedi Temple Guards | Strength on the Light side |
What gives a lightsaber its color? The color of the lightsaber, according to Jedi lore, is derived from the color of the kyber saber crystal, which is at the heart of the lightsaber. Except, of course, for the case of the red lightsabers, which have been turned red from the dark side.
What about your young Padawan’s lightsaber? Any trip to a store that sells toys will yield the opportunity to purchase and own your very own lightsaber. There are those that collapse and extend, and those which just stay extended, but from our use of the force (and the StellarRAD Handheld SpectroRadiometer), none seem to actually be laser weapons. How do we know? We sensed it using the force, and also by taking spectra.
Below is a spectra taken of a red laser, using a common red laser pointer. Expectedly, the single wavelength of the solid-state coherent emission is evident in the singular peak.
The next spectra below, taken from a red lightsaber, borrowed from a resident Sith-Lord-in-Training, emits a very different spectrum. Noting that the spectrum is broader, clearly, this padawan is not yet truly taken to the dark side… the plastic casing diffuses its LED sufficiently.
For the young Jedi wielding a green lightsaber in the house, the video below shows the real-time capture of the spectra when the lightsaber is engaged and disengaged. From viewing the spectra we can see that although the saber looks green, it does reveal a tail into the red range. Does this mean our young padawan learner is conflicted, possibly leaning to the Dark Side? Only time will tell.
So if Kyber crystals were made of laser diodes, could the table above be their laser heritage?
View Application Note PDF: Lightsaber Technology, Fact or Fiction
