I honestly don't know, but I think I can make an educated guess.
It seems like it's one of those instruments that we put our eyes on and inside there are some images that we can pass from one side to the other. Did I get it right?
If not, I would bet that it would be an instrument for testing vision. LOL
It had small images on the "disc" that when you clicks the button, it moved to the next one.
I've had contact with some things similar to this, but not like the photo. You could see animals, for example, from inside.
Yes. That is what it was. It was a fun toy for the kids.