My team at Meta has spent the last decade advancing solutions for vergence-accommodation conflict (VAC) in virtual reality. This work led to Meta's first public exhibition of VR varifocal displays at SIGGRAPH 2023. However, I often receive questions about how we might similarly solve VAC in glasses-form-factor AR displays.
Nature Communications just published our most recent work on waveguide holography, which is a potential answer to this question.
www.nature.com/articles/s4146...
Within the AR industry, waveguide displays are widely deployed and developed as a potential approach to achieve eyeglasses-form-factor devices. While it's hard enough to deliver a compelling field of view and artifact-free images with waveguides, the question remains how the industry might ultimately solve VAC with such displays - without adding yet more hardware bulk and complexity. To date, designers have added refractive lenses to bias the focus, but there hasn't been a practical way to continuously adjust it, as we do with VR varifocal displays.
Our new publication outlines how to modify the design of existing AR waveguide displays to support natural accommodation depth cues. In fact, this solution goes beyond varifocal, depicting a complete hologram with accurate accommodation and ocular parallax depth cues. Akin to our past work on étendue-expanding holographic displays, our team discovered new methods to accurately calibrate the light transport through pupil-replicating waveguides. In our laboratory experiments, this has allowed for high-quality images to be depicted across multiple planes of focus with a compact hardware prototype.
What does this mean for the industry? There now exists hope that VAC can be resolved with waveguide displays, without adding yet more optical components between the user's eye and the physical world. Technically, the main challenge this work begins to overcome is finding a way to make laser illumination compatible with pupil-replicating waveguides. It's the beginning of the journey, but we're excited to share our approach and current results.
Congrats to Changwon Jang and Kiseung Bang for leading this joint research between Meta and Seoul National University. I'm happy to finally have the beginning of a practical answer to VAC in AR.