eggplant problem

[framer]

Somthing is happening to my eggplants. Suddenly the leaves have tiny pin holes in them which makes the leaves look like fine lace. I have looked at the leaves, both top & bottom & I can't see any kind of insect. Possibly they do their dasterdly deed at night & then leave during the day. Most of the leaves look like this. The plants are over six feet tall & still setting fruit with a good many blooms still coming on. Does anyone have a clue?
Thanks
framer. zone 8a