The heat would come from the phone itself and enter a low-power mode while in the process via an app. The tech could allow the smartphone to analyze the display’s structure, spot anomalies, and effectively fix any problems by remolding itself with heat as close to its original form as possible.
The patent mentions the process is lengthy and could be done overnight in a specifically-designed dock. It’s also worth mentioning that the tech doesn’t apply to cracked screens. Motorola already offers shatterproof displays with its Moto Z Force lineup of phones. LG also made a self-healing smartphone back in 2013 called the LG G Flex, mostly distributed in Korea, although its screen was made of glass.