And in 20 minutes, hopefully you were asleep. Otherwise, you’d likely be at full dark adaptation and find new light sources. Your pupils take seconds to adjust, but it takes 20 minutes for your eyes to replenish the rhodopsin, the chemical that amplifies your retinas. It gets bleached in seconds, which is why it takes so long to go back to full adaptation. Red light does not bleach rhodopsin, hence it’s use in dark activities. That’s also why “pirates” used eye patches: one eye kept it’s rhodopsin to see below deck.
And in 20 minutes, hopefully you were asleep. Otherwise, you’d likely be at full dark adaptation and find new light sources. Your pupils take seconds to adjust, but it takes 20 minutes for your eyes to replenish the rhodopsin, the chemical that amplifies your retinas. It gets bleached in seconds, which is why it takes so long to go back to full adaptation. Red light does not bleach rhodopsin, hence it’s use in dark activities. That’s also why “pirates” used eye patches: one eye kept it’s rhodopsin to see below deck.