Any good suggestions on control time of TV or iPad video for kids around 5y?

My son loves watching kids video and series like super wing or others. I try to make sure he watched under 1hr most per day. But somehow I still feel it is a bit more, maybe I should reduce it under 45mins. Another question is how to best protect his eyes. I played with some video games around 12, as far as I remember that was when my sights got impacted and need to wear glasses. For now I cast the video to TV. Any good suggestions to make sure that it won’t impact eye sight at this little age?