A NEW HOPE
(1977)

Here is a concept of the hero (looking a lot like Lucas) holding the earliest idea of the lightsaber.
Then McQuarrie's vision of that same character.

...

Originally George Lucas envisioned the lightsaber to be a widely used weapon on the Star Wars universe.
Below are Ralph McQuarrie pre-production paintings. Stormtroopers & hero's patrol the hallways of the Death Star with lightsabers in hand.

Here is a close-up of a hero battling Darth Vader. The "McQuarrie Concept Lightsaber" in hand.

Next are pre-production publicity photos of Vader.
The first pic is how the public saw the release.

Next are pre-production publicity photos of Vader.
The first pic is how the public saw the release.

The Linhof was painted over with another version of McQuarrie's lightsaber.

An article published in the late 70's shows the public a glimpse, although highly inaccurate, at a lightsaber chart.
An amusing note listed under Luke's version, "...an augmented Graflex flashgun...". That is EXACTLY what it turned out to be.

The Final Versions Of "A New Hope" Lightsabers