According to a report from Korea, Facebook recently hired a large number of OLED engineers, in Korea, through Facebook's Reality Lab. The company is now hiring more OLED experts to work at its Reality Lab US offices.
Facebook new job openings includes many roles in OLED display technologies. The company does not aim to start producing OLED, of course, but to secure technology to develop innovative OLED displays and applications in VR and AR devices.
Many recent VR devices, based on mobile display architectures, adopted LCD over OLED display due to the lower cost of the LCDs (coupled with high performance). But according to the report Facebook's view is that next-generation devices will adopt OLED displays, as performance increases and the price gap with LCD gets lower.
We recently ran a story that speculated on Facebook's adoption of OLED microdisplays (specifically from eMagin) in future VR headsets.