Excuse me, what is the technical term for the photo frame in the photo studio?

This is the name given by the studio itself. Not all studios are unified. You can go to your consulting studio and ask them to send you pictures. For example, your Korean three-dimensional frameless prints of 12X 12 may be called Milla prints in other studios, or Greek prints and Sophia prints. Anyway, all your posts are made by the studios themselves, and not all studios are unified at all.