The computer that Scotty uses in the Plexicorp scene appears to be a Macintosh Plus, but its internals were completely changed for filming. Its screen was replaced with one from an IBM PC to make it easier to synchronize its video refresh rate with the film camera's frame rate, and the "transparent aluminum" animation was created on an IBM PC by computer graphics company Video Image.

At one hour and one minute into the film, when Dr. McCoy hands Scotty the computer's mouse, is one of the few times James Doohan's missing right middle finger is visible in the entire franchise. The finger was shot off during the invasion of Juno Beach on D-Day.

The computer that Scotty uses to show transparent aluminum was originally going to be an Amiga, but Commodore would only give permission if they bought their own. Apple Computer was willing to give them a Mac for free.

Conductive transparent materials do exist (see ITO https://en.wikipedia.org/wiki/Indium_tin_oxide), but this is not it.

I found one here: https://makezine.com/article/science/transparent-aluminum/

Also a video of it being used as Armor? https://www.youtube.com/watch?v=RnUszxx2pYc