Heads-Up Display: Mostly replaced by Augmented Reality, although they still fit them to vehicles (from individual flitters through starships) as a backup system just in case the AR – or, more likely, the underlying networking – is out for some reason. These days they use smartglass rather than reflection, though.
This is a companion discussion topic for the original entry at https://eldraeverse.com/2014/06/27/trope-a-day-heads-up-display