A plot point in the 1986 film Star Trek IV: The Voyage Home features the fictional material transparent aluminium. Around the same time, actual transparent aluminium was patented.
Last week I wrote about the proposal that ideas from science fiction could be patented provisionally until they became technically feasible. Well, that led me down a research rabbit hole to a list of real technologies originally suggested in fiction. And one entry in that list surprised me: transparent aluminium.
If you’ve seen the fourth Star Trek film you’ll know what this is all about. In the film, the heroes take a stolen Klingon ship back in time to 1986 to kidnap some whales. They need them alive, so one of the challenges they face is retrofitting the Klingon ship with a gigantic holding tank. Scotty the engineer builds one out of transparent aluminium, trading the formula for this fictional material for a few free panels. It is not apparent to me why the tanks needed to be transparent, but no matter. Transparent aluminium is another piece of Star Trek technobabble designed to give the screenplay a futuristic edge (one of many). Except that, around the same time, someone actually patented it.
Technically speaking, aluminium oxynitride is a ceramic. It is made by taking a powder and compressing it into the desired shape, baking it, and then polishing it to a lovely smooth finish. In addition to aluminium the powder has oxygen and nitrogen, but it has aluminium and it’s transparent enough to function as a window… so it’s transparent aluminium.
This material is officially called ALON after its three elements (Al, O, and N). It’s bullet-proof – as long as the bullets aren’t too large – and when Elon Musk’s cybertruck was demonstrated there was a popular theory that the windows were made out of transparent aluminium. He was going for the Blade Runner aesthetic, but – as always – Star Trek was there first.
The Generalist Academy 
Phil on Facebook observed that, in the Star Trek movie, they don’t actually build the tank out of transparent aluminium, they just trade the formula for some other materials because they have no money. The finished tank does have windows, but according to the shooting script they’re made out of six-inch-thick plexiglass.