Colloquia & Guest Speakers

Optics for wearable displays and sensors: VR, AR, Smart Eyewear and beyond

Bernard Kress, Google [X] Labs, Mountain View, CA

Wednesday, April 29, 2015
2 p.m.–3 p.m.

Goergen 109


Helmet Mounted Displays (HMDs) and Head Up Displays (HUDs) have been used extensively over the past decades especially within the defense sector. The complexity of the design and the fabrication of high quality see-through combiner optics to achieve high resolution over a large FOV have hindered their use in consumer electronic devices, mainly due to the drastic Industrial Design constrains in size, weight, shape and costs. Non see through VR (Virtual reality) Head Mounted Displays have also been used in the defense sector for simulation and training purposes, over similar large FOV, packed with custom head tracking and eye gesture sensors. Recently, a paradigm shift to consumer electronics has occurred as part of the wider wearable computing effort. Technologies developed for the smart phone industry have been used to build smaller, lower power, cheaper, electronics. Similarly, novel integrated sensors and micro-displays have enabled the development of consumer electronic smart glasses and smart eyewear, professional AR (Augmented Reality) HMDs as well as VR headsets. Reducing the FOV while addressing the needs for an increased exit pupil (thus allowing their use by most people) alongside stringent industrial design constrains have been pushing the limits of the design techniques and technologies available to the optical engineer (refractive, catadioptric, micro-optic, segmented Fresnel, waveguide, diffractive, holographic, …). The integration of the optical combiner within conventional meniscus prescription lenses is a challenge that has yet to be solved for the consumer market. We will review how a broad range of optical design techniques have been applied to fulfill such requirements, as well as the various head-worn devices developed to date. Finally, we will review additional optical technologies applied as input mechanisms (eye and head gesture sensing, gaze tracking and hand gesture sensing).


For over 20 years, Bernard has made significant scientific contributions as a researcher, professor, consultant, advisor, instructor, and author, in the field of micro-optics, diffractive optics and holography for research, industry and consumer electronics. He has been involved in half a dozen start-ups in the Silicon Valley on optical data storage, optical telecom, optical position sensors and display (picos, HUDs and HMDs). Bernard holds 28 international granted patents and 30 patents applications. He has published more than 100 proceeding papers and 18 refereed journal papers. He is a short course instructor for the SPIE on micro-optics, diffractive optics and wafer scale optics. He has published three books edited by John Wiley and Sons “Digital Diffractive Optics” (1999), “Applied Digital Optics” (2007) and Mac Graw Hill “Optical System Design: Diffractive Optics” (2005) and a field guide by SPIE “Digital Micro-Optics” (2014). He has been chairman of the SPIE conference “Photonics for Harsh Environments” for the past three years. He is currently with Google [X] working on the Google Glass project as the Principal Optical Architect.