Luke didn't use his lightsaber

So, something strange I noticed in the original Star Wars film (Episode IV)- something that totally goes against the conventions of most movies. In the beginning of the film, Luke receives his father's lightsaber from Ben Kenobi. Later, we see him practicing with it onboard the Millennium Falcon. And then... well, that's pretty much it. He does not use it for the rest of the movie. In fact, I'm not sure you even SEE the thing after that scene on the Falcon. He doesn't have it with him on the Death Star, or when he gets to the rebel base or... even at the awards ceremony.

I never really noticed this before. But in retrospect, it is very odd. Especially when you consider the fact that Lucas had no idea if Star Wars was ever going to HAVE a sequel. Normally, when a hero in a movie gets a 'cool legendary weapon', he damn well uses it. But not here. So, is that bad writing? or Forethought? or... what? I'd like to chalk it up to the latter—that Lucas knew that Luke would slowly build up to using his lightsaber. But... well, I just don't know. Either way, I don't recall it ever mattering that much to me. In fact, I thought the blasters were cooler anyway.