Trope-a-Day: Hologram

Hologram: This future does have these (and uses them an awful lot for user interfaces, it must be said, since dynamically reconfigurable interfaces are (a) shiny, and (b) easy to implement this way); however, as the trope points out, there are properly not “holograms”, but really “volumetric displays”, even though the former is easier to say.  Which is why the future calls them “trigraphics”.

On the trait list: not opaque, do require an emitter and indeed line-of-sight to it (which means, yes, stick your hand into it and it will clip; mitigated in some circumstances by using lots of emitters at different positions/angles; also, things like trivision viewers and hololiths solve the problem by projecting the trigraphic inside a transparent solid block), have deliberate glamor failure to ensure no-one confuses them for real objects, and do need a camera to see things.