>>379894476
Ok I found it. It wasn't a paper or patent (although one might exist).
It was from a presentation by formerly Facebook Reality Labs at Display Week 2021.
Imagine related. Not much info is available about the presentation other than this one article: 

https://www.dday.it/redazione/39556/visore-vr-grande-come-un-paio-di-occhiali-i-facebook-reality-labs-mostrano-gli-ultimi-progressi