Playing with HMDs and VR in the 90s, I came across a book that described the efect as a "virtual hangover" with effects that could last up to 72 hours, which wa

Playing with HMDs and VR in the 90s, I came across a book that described the efect as a "virtual hangover" with effects that could last up to 72 hours, which was why AF pilots using them in training were grounded for that period. It's not an uncomon effect for any close focusing to distort vision temporarily, especially if your eyes are tired. I visited an opthalmologist last year because of persistent ghosting at night, and it turned out to be from reading laying on my side in bed causing one eye to partially cross but not fully uncross until morning.