I'm really not worried, I was just curious if it was a thing or not. Like if it had a name. But thank you very much!
This is a very interesting symptom, and I am not sure what is causing it. As a guess, it is possible that there is a change in the astigmatism of your corneas with lid closure, which then changes your vision. I truly don't think you have a serious problem. However, if you're worried, see an ophthalmologist for a comprehensive exam.