What is the name of this?

I received a pass-a-long plant from a quilt friend a few years ago. She didn't know the name of this plant but said it would bloom with lovely flowers. She was certainly right! It's growing as a house plant and looks like it belongs to the Iris family. I can't find the name of it but I don't mind...it is so lovely. The bloom only lasts for about 8 hours and only blooms in the daylight. I placed the bloom on a pink towel so you could see it better.  Do you know the name?