With applications ranging from gaming to professional uses such for assembly, maintenance information supply, and pilot training in flight simulators, virtual reality glasses and their supporting systems are becoming more established. A crucial aspect of virtual reality presentations is the display technology. OLED microdisplays are receiving growing attention due to their technological advantages.
The Fraunhofer FEP has long-term experience with customized OLED microdisplays. Within the EU-funded H2020 project LOMID (Large cost-effective OLED microdisplays and their applications) which is led by scientists at the Fraunhofer FEP, a new generation of large area OLED microdisplays has been developed which focusses on both virtual-reality (VR) and augmented-reality (AR, the latter will be tested within the project in visual prosthetics).
“Economical processes (e.g. based on 0.18 and 0.35 µm lithography) are being developed at the CMOS silicon foundry and special attention will be given to the interface between the top metal electrode of the CMOS backplane and the subsequent OLED layers,” said Mike Thieme, project manager at LOMID contributor X-FAB. “In order to keep the CMOS manufacturing at low cost, numerous design rules have been pushed to their limits.”
Additional challenges such as conformability of the OLED microdisplays will be addressed to allow a bending radius of 50 mm.
X-FAB Dresden GmbH & Co. KG will manufacture the CMOS backplane wafers, which will be used by MicroOLED S.A.S. for OLED microdisplay fabrication. These microdisplays will be applied by Limbak SL for virtual reality glasses. The research organization CEA-Leti develops processes to realize the bendability and an appropriate encapsulation, while Fraunhofer FEP focuses on the IC design of the CMOS wafer. The University of Leipzig works on inorganic transparent FET materials, and the University of Oxford develops prosthetics for people with impaired vision. The company Amanuensis is assisting the consortium with coordination, dissemination and exploitation activities.
The project will run until Dec. 31, 2017 and will provide a high-performance OLED microdisplay with new functionalities addressing a wider range of applications.
First prototypes of the project OLED microdisplays and a presentation on the state-of-the-art of the technology and developments will be given by Dr. Beatrice Beyer (LOMID coordinator, Fraunhofer FEP) on the SID-ME Spring Meeting 2017.