One of my hobby projects while in University was to do OCR on book scans. Doing character recognition was solved, but finding the relationship between character

One of my hobby projects while in University was to do OCR on book scans. Doing character recognition was solved, but finding the relationship between characters was very difficult. I tried "primitive" neural nets, but edge cases would often break what I built. Super cool to me to see such an order of magnitude in improvement here. Does it do hand written notes and annotations? What about meta information like highlighting? I am also curious if LLMs will get better because more access to information if it can be effectively extracted from PDFs.