I suggest you never wear it to sleep. It is very harmful to the eyes, compressing the optic nerve and ensuring that the eyes are blurred at night will hurt the eyesight. This is my personal experience. Doctors advocate natural sleep.
What is natural sleep? Generally, it is measured by the decline of physical activity and sensory sensitivity.
In addition, some physiological indexes, especially the awakening threshold, also indicate that the third and fourth stages of slow wave phase are deep sleep. As for the depth of heterogeneous sleep, it is difficult to judge, because it is not only manifested in the relaxation of muscle tension, but also often turns over all over, and the muscles of the face and fingers twitch. In terms of feeling, it is difficult to wake up the sleeper by external stimuli, but it is easy to wake up when the stimuli have special significance or are related to the content of his dreams. These contradictions show that during heterogeneous sleep, an active process in the brain can cut off its connection with external stimuli. If judged by the activity of autonomic nervous system, heterogeneous sleep is closer to awakening state. If the sleeping person is woken up at this time, he will say that he is sleeping. On the other hand, waking him up in the slow wave stage means that he doesn't sleep well. It is speculated that this subjective sleep consciousness may be related to his dreams. To sum up, it is difficult to accurately measure the depth of sleep, and the current trend is to regard out-of-phase and slow-wave phase as two independent States.
Some autonomic nervous activities change with the development of sleep process, and there seems to be little correlation between them. For example, the body temperature gradually drops from sleep, reaches the lowest point in 5-6 hours, and then gradually rises. It has been suggested that oral materials can still be learned during sleep, but the analysis of EEG proves that sleepers are actually in a hazy state. Sleepwalking mostly occurs in the second stage of slow-wave sleep, while sleepwalking occurs in the fourth stage of slow-wave sleep without exception, both of which are generally irrelevant to the content of the dream.
Therefore, it is recommended to go to bed early and get up early when sleeping, which is great in spirit.