system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5 Why our eyes get "cloudy" when we are waking up. What physically is the "cloud" in our eyes?

I'm talking perfectly healthy eyes, when I'm still waking up they get cloudy every few blinks.
gpt
Your tear film has three layers: mucous, water, then a lipid layer on top. The lipid layer keeps the water from evaporating off your eyes too quickly. As you sleep, if your eyes are open even a little bit, that water layer can evaporate so when you wake up, all that is really left is mucous and the lipid layer. Without the water layer, your tear film is thicker and is more difficult to see through, hence that cloudiness. But when you blink a few times, it clears up as the lacrimal gland releases tears to add to the water layer.