Blindfolds have been used for centuries to prevent sight, usually during
kidnappings but really in any situation where you don't want someone to see
something or somebody or someplace.
It's 2018, let's get creative. Imagine a blindfold-like device that went around your
head (that also corrected
that I-can-kind -of-see-in-that-crack- by-my-nose
problem) and, for the most part, allowed regular sight. Using cameras and
receiving digital information via wifi, the digital blindfold would see QR codes (or
something similar) to automatically "blindfold" computer screens, rooms,
faces(think digital camera facial recognition) and would even redact writing on
pages (blocking classified information, etc.). Also, through wifi or some other
medium, the blindfold would turn into a deaf-fold, using speakers to play white
noise when signaled to do so. The nose-fold could be an option for super-secret
chef locations, but I do not see this becoming a popular option (sprays vinegar to
mask scents?) nor would the hand-fold (a glove-like device that inflates upon
signal, depriving the user of any fine motor skills).
To prevent users from hiding codes or otherwise circumventing the system, it
would be made with security in mind. The blindfold, using motion sensors,
would also generally know where it is, and looks for certain visual markers to
verify locations. If it does not see them, it will automatically alarm. The wifi
would also require some kind of constant signal so that this cannot be
circumvented. If no signal is established and constantly received, white noise
will automatically play.