LG's "Project B" rollable phone may have surfaced in a leaked patent document
The blog LetsGoDigital claims to have gotten hold of an application made by the OEM LG to the USPTO. Its diagrams may show that it pertains to Project B, a new kind of phone with what is called a rollable display that may or may not succeed the innovative Wing. The new document may demonstrate how the company intends to make this use of flexible AMOLED work in real life.
A different manufacturer, TCL, is known to have a similar concept device. However, unlike that prototype, LG's apparent new IP allows the user to pull the display outward on either side, thus giving a screen of a potentially very variable length compared to its "collapsed" mode. It apparently does so through relatively simple spring-loaded mechanisms...which are hopefully very robust in practice.
LG also seems to indicate that the display "extensions" can be put to different uses relative to the "main screen" contents, similar to Samsung's Flex Mode on the Galaxy Z Fold2. They might include a frame-by-frame view or scrubber while watching videos, or switching between different camera views in cases of multi-angle coverage.
LetsGoDigital has also generated some high-quality renders based on LG's diagrams, although they cannot offer an insight as to dimensions for the device in the image, the size of its extended or collapsed screen included. However, as the application in question is listed as filed in March 2019, it may still be some time before consumers get to find this information out for themselves.