We know about sound-on-display technology for quite some time. LG introduced it on its TVs and other manufacturers followed suit. At this year’s MWC 2019, LG introduced the G8 ThinQ with a Crystal Sound OLED display, basically turning part of the phone’s screen into a speaker, eliminating the need for an earpiece.
A recently uncovered patent filing reveals that Apple might be working on something similar. The patent describes the pistonic motion (referring to the diaphragm movement) of the speaker and how the entire display can be turned into such a hardware component.