Thanks so much for bringing this subject up lisasays! It's something I've been thinking about lately -- and thanks to deliquesce for the very useful info -- especially the names. Now I have a name for it. Yea!
I have this a lot. Now I know they are hypnopompic, as all the times I remember are in waking. I will wake, see something strange, even get out of bed and still see it until I get closer or try to touch to verify the visuals (*That's* the part that had me worried. I clearly am not sleeping at that point.) Most recent one was seeing big pipes on the ceiling, like 4" PVC pipe. Had a really long series of related ones years ago where I'd be thinking something was wrong with the roof. It was blown off and there were the stars, there were huge leaks, you name it, all kinds of variations on the theme. Would open eyes, and still see it. We had these slanting ceilings there, and my husband kept waking up to see me standing on the bed with my hands touching the ceiling. Yeah, you can imagine what he thought(!)...
Good to know they are so common and not to worry.