If i look at a clock and blink a few times, the numbers look like they actually jump with my blinks, a lot, unless i deliberately focus and blink slow?

Normal : When you blink, your eyeballs actually rotate upward (in most people with an intact Bell's phenomenon) so as to protect the cornea. As you blink very fast, as in fluttering your eyelids, it's very possible that an l.e.d light source would appear to be moving up & down. In normal situations, you would not usually pay attention to this subtlety. When blinking slowly, eyes already back in normal posi