Serious question - is semen introduced to the eye harmful to good ocular health?

Depends on the acidity (and saltiness) and if the semen-er has ANY diseases. Avoid if at all possible... it's easy, just don't look.

I already have bad ocular health, so bring it on!
you tell me it appears that you've been hit in the eye a couple of times
anything is bad when your eye is stuck shut!
There are others holes on the women's body that are meant to be enjoyed. Go ahead, be crazy, experiment. Next time try the vagina for a change!
Well it's not meant to be used to lubricate the eye. Semen's goal is to invade cells, so there are millions of tiny sperm invading eye cells. Doesn't sound pleasant. Probably best to wash it out after with eyedrops or to blink before it hits the eyes.
Yes, it is harmful and should be checked out by a doctor. There are actual cases of STDs ending up in people's eyes, not to mention basic eye infections that this can cause.