Apple's foldable iPhone could use a hybrid OLED panel in the future, with Apple putting a focus on avoiding the crease seen on some foldable smartphones.
The key element of devices like Apple's rumored "iPhone Fold," a potential folding iPad, and Samsung's Galaxy Fold lineup is that they either have or will get folding displays. However, that very feature could cause problems that can spoil the appearance of the device.
Small crumples can appear in highly flexible displays when they are folded. According to sources of The Elec, Apple is working to avoid this from happening, by demanding display suppliers LG and Samsung develop hybrid OLED panels.
A typical rigid OLED panel uses glass as a substrate, which is usually fairly inflexible. The flexible OLED panels tend to use a plastic substrate, which is also encased for added protection.
The hybrid panel would use both glass and plastic for the OLED panel, which also uses the thin-film encapsulation method.
Another part of the problem is in production, as Polyimide varnishes are put onto a glass substrate, with the glass later removed using lasers to create the plastic layer. That plastic layer can be warped by the laser's heat, creating the crumples.
In answer to Apple's urging, Samsung Display and LG are working on an ultra-thin glass substrate that could be used in a hybrid OLED panel. The substrate would be 2mm thin, rather than the typical 5mm, making it easier to flex.
As it is under development and not at a stage where its ready for commercialization, the display technology may not reach Apple's supply chain for a few years. As for what it could be used for, a source says that the crumples aren't that noticeable on a smaller display, but are on a larger version, making a hybrid OLED panel more suitable for a foldable iPad.
This hybrid approach isn't the only way Apple is trying to tackle foldable display issues. In may, itw as reported that Apple was keen on an OLED panel that was made thinner due to not requiringa polarizing layer.