Samsung and LG recently secured patents on new dual-screen smartphone designs featuring displays on both their front and back panels. The concepts were awarded by the United States Patent and Trademark Office earlier this year, with Samsung's solution seemingly being envisioned as a more technologically advanced device; while LG's design includes a traditional fingerprint reader mounted on the back of the concept phone, below its secondary screen, Samsung appears to have opted for an in-display scanner.
Even though Samsung's vision also includes significantly smaller bezels, the patent documentation states that the borders surrounding the screen aren't part of the filing, whereas LG's design is more defined and realistic. Neither South Korean tech giant mentioned the type of panels it would use in such a dual-screen device, though at least one module would likely be of the OLED variety should such devices ever be commercialized. Having two screens could significantly impact the battery life of a device, making the choice of OLED more obvious as such panels are able to conserve energy by only lighting up individual pixels that are needed, i.e. leaving the black ones turned off, which also delivers more accurate colors. Both Samsung and LG have been committing significant resources to OLED manufacturing in recent years, though the former is still the undisputed industry leader in terms of output capacity.
OLEDs are also believed to be the crucial component of foldable smartphones, the first major form factor change in the mobile industry in over a decade. Samsung is already set to release its first bendable handset in the first half of 2019, whereas LG is expected to procure display panels for that category of devices from other manufacturers such as Xiaomi and OPPO. It's presently unclear whether either company has any immediate plans to commercialize dual-screen devices, though such offerings have already been delivered by the likes of Meizu and YotaPhone.