This comes from the latest research results from the European funded project LOMID (Large cost-effective OLED microdisplays and their applications).
Large-area OLED microdisplays, combined with advanced free-form optics provide an ergonomic and lightweight solution for the design of VR glasses, and higher frame-rates will reduce the motion sickness for users.
Ultra-compact optics, designed by project partner LIMBAK, seamlessly combine two display chips per eye, making four in total for the entire headset. With two WUXGA microdisplays per eye, the headset has a total resolution of 4800 × 1920 pixels, which is close to 5k. This design facilitates very highly effective display resolutions and a wide field of view (>100°) for an excellent immersive VR sensation.
Moreover, the optics scientists of LIMBAK have been able to decrease the display-to-eye distance needed in the headset, lowering it to only 37 mm (compared to 60-75 mm in most conventional headsets). This ultra-compact optical design reduces the headset size to about a quarter of the volume and half the weight of a conventional headset while maintaining the same field of view.
“To offer such high framerates of 120 Hz and thus high data rates, we have extended the parallel interface of the OLED microdisplays. The display mode can be configured flexible from hold-type to impulse-type. The latter allows the elimination of motion artifacts and flicker with a special rolling emission mode,” said Judith Baumgarten, scientist in the IC and System Design department at Fraunhofer FEP. “The chip also provides special look-up-tables for gamma correction – each channel (red, green, blue, and white) can be calibrated individually. We achieved a superior image quality with a very high contrast ratio of >100'000: 1 at extraordinary low power consumption.”
The tiling of multiple OLED-on-silicon microdisplays inside the system has helped to reduce its form factor and weight while increasing resolution to a level not easily achieved by conventional TFT-based AMOLED displays in VR headsets currently due to their typical pixel density limits.
LOMID project partner X-FAB developed economical processes at the CMOS silicon foundry, paying special attention to the interface between the top metal electrode of the CMOS backplane and the subsequent OLED layers. Partner Microoled S.A.S. is responsible for the fabrication of the whole OLED microdisplays – the key component for these kinds of VR glasses using those CMOS backplane wafers.
Scientists from Fraunhofer FEP will present a LOMID headset prototype as well as research results at booth No. 322 during the AWE Europe 2018, which takes place Oct.18-19, 2018 at MOC Exhibition Center Munich, Germany.