OLEDON announced that it has developed a plane-source evaporation shadow mask process that can achieve a shadow distance of 0.38um - which can enable OLED display resolution to reach 2,250 PPI. The company says it technology will be able to achieve 3,300 PPI in the future.
OLEDON is not alone in the development of plane-source evaporation technology. In November 2016 Sunic Systems announced that it developed a similar AMOLED production process - that can also achieve 2,250 PPI. It may be that Sunic and OLEDON are collaborating on this, it is not clear.
A good VR experience requires very high resolutions - which is driving the need towards high pixel-density AMOLED displays. In May 2016 Samsung demonstrated a 5.5" 3840x2160 - which reaches 806 PPI, and according to reports Samsung were able to produce a 1,200 PPI AMOLED in March 2017.
Google is also reportedly developing a high-density OLED displays for VR headsets. Last week Google revealed that the company has partnered with "one of the leading OLED makers" on a secret project to develop a high-end VR display that will have a resolution of 20 million pixels per eye.