You wear night lenses when you sleep.  While you sleep, the lenses correct your eyes.                                                                                                                            The lenses do not touch your cornea, but float on your tear film.                                                                                                                                                                    Due to pressure difference, the front of your eye takes on a different shape, that difference in shape ensures that you can see sharply during the day without glasses or lenses.                                                                                                                                               

A good solution if you often suffer from dry eyes! But also ideal for exercising freely or if you simply do not want glasses.           

Night lenses give you comfort and freedom when this is most important, namely when you are awake.