SEOUL, South Korea (AP) — LG Display Co., a supplier of Apple's iPhone screens, said Wednesday that it will invest 1.99 trillion won ($1.75 billion) to produce flexible displays for smartphones, in a sign that more high-end smartphone makers may adopt flexible screens in the near future.

The South Korean company said mass production of flexible displays will start in late 2018, at a scale that will supply enough 5.7-inch sized flexible screens for 3 million handsets per month.

The flexible displays will be made of advanced materials called OLEDs, or organic light emitting diodes, which display more saturated colors, such as a darker black, than LCDs.

While Apple still uses LCD screens for its iPhones, a growing number of mobile phone makers have adopted OLED screens for their flagship phones as they have resolved battery-draining and heat problems associated with the technology. Market watchers say even Apple might use the OLED screens for its iPhones as early as next year.

The OLED screen is lighter and thinner than other display screens and has more design flexibility. It can be folded and bended.

LG Display focused initially on investing in large-sized OLED screens for televisions while its small-sized screens were mostly made of LCDs to meet demand from its key clients, including Apple and its affiliated company LG Electronics.

With the latest investment, LG is trying to catch up with its rival Samsung Display in the small-sized OLED screens. Samsung dominates the supply of OLED screens for mobile phones. For years, Samsung Electronics used the OLED screens for its flagship Galaxy smartphones and recently it has adopted curved OLED screens for its Galaxy Edge series smartphones that feature displays that wrap around corners of the devices.

LG Display's biggest client for mobile phones is Apple.

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