In June 2017 JOLED announced that it started to sample 21.6" 4K OLED panels, with plans to initiate low volume production at its 4.5-Gen pilot inkjet production line. JOLED announced today that it has began commercial shipments of these panels. We do not know JOLED's first customer but it is likely to be Sony.
JOLED says that it has now achieved the necessary product quality and production yields. The product was already selected for use in medical monitors (again, we believe this is Sony, who we know received JOLED's first samples and already has its own 25" OLED medical monitor that uses Sony's own OLEDs). JOLED also aims to ship these panes to other OLED monitors applications.