Accommodation and comfort in head-mounted displays

Abstract

Head-mounted displays (HMDs) often cause discomfort and even nausea. Improving comfort is therefore one of the most significant challenges for the design of such systems. In this paper, we evaluate the effect of different HMD display configurations on discomfort. We do this by designing a device to measure human visual behavior and evaluate viewer comfort. In particular, we focus on one known source of discomfort: the vergence-accommodation (VA) conflict. The VA conflict is the difference between accommodative and vergence response. In HMDs the eyes accommodate to a fixed screen distance while they converge to the simulated distance of the object of interest, requiring the viewer to undo the neural coupling between the two responses. Several methods have been proposed to alleviate the VA conflict, including Depth-of-Field (DoF) rendering, focus-adjustable lenses, and monovision. However, no previous work has investigated whether these solutions actually drive accommodation to the distance of the simulated object. If they did, the VA conflict would disappear, and we expect comfort to improve. We design the first device that allows us to measure accommodation in HMDs, and we use it to obtain accommodation measurements and to conduct a discomfort study. The results of the first experiment demonstrate that only the focus-adjustable-lens design drives accommodation effectively, while other solutions do not drive accommodation to the simulated distance and thus do not resolve the VA conflict. The second experiment measures discomfort. The results validate that the focus-adjustable-lens design improves comfort significantly more than the other solutions.

Chromablur

“…But the coupling is broken by conventional stereoscopic displays because such displays require the viewer to converge to one distance (that of the virtual object) while accommodating to another (the display screen). e resulting vergence-accommodation con ict causes visual discomfort [Ho man et al 2008;Koulieris et al 2017;Lambooij et al 2009;Shibata et al 2011], reductions in performance [Akeley et al 2004;Johnson et al 2016;Konrad et al 2016;Maiello et al 2014], and distortions of perceived depth [Wa et al 2005]. Our work provides an opportunity to control accommodation more e ectively and thereby minimize the vergence-accommodation con ict.…”

“…One can couple the ChromaBlur rendering technique and focusadjustable lenses [Johnson et al 2016;Konrad et al 2016;Koulieris et al 2017] to create a display in which accommodation can be driven reliably to the intended distance. Eye tracking could be used to estimate the viewer's xation distance from moment to moment.…”

Review of the Augmented Reality Systems for Shoulder Rehabilitation

“…The vergence-accommodation conflict [43], and the mismatched accommodation between virtual content and real-world scene for optical see-through (OST) HMDs [44].…”

A QoE and Simulator Sickness Evaluation of a Smart-Exercise-Bike Virtual Reality System via User Feedback and Physiological Signals

“…With VR in such increasingly high demand across a broad spectrum of industries and with a large variety of uses, it becomes necessary to have a better understanding of how the quality of VR content can directly affect user experience. It is well documented that HMDs often provoke discomfort and even nausea [19], a condition known as simulator sickness. Being a sub-category of motion-sickness, simulator sickness arises due to sensory conflict between what the users see and what they feel [20].…”