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Due to the additive light model employed by current optical see-through head-mounted displays (OST-HMDs), the perceived contrast of displayed imagery is reduced with increased environment luminance, often to the point where it becomes difficult for the user to accurately distinguish the presence of visual imagery. While existing contrast models, such as Weber contrast and Michelson contrast, can be used to predict when the observer will experience difficulty distinguishing and interpreting stimuli on traditional dis-plays, these models must be adapted for use with additive displays. In this paper, we present a simplified model of luminance contrast for optical see-through displays derived from Michelson's contrast equation and demonstrate two applications of the model: informing design decisions involving the color of virtual imagery and optimizing environment light attenuation through the use of neutral density filters.
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Analysis of the Saliency of Color-Based Dichoptic Cues in Optical See-Through Augmented Reality
In a future of pervasive augmented reality (AR), AR systems will need to be able to efficiently draw or guide the attention of the user to visual points of interest in their physical-virtual environment. Since AR imagery is overlaid on top of the user's view of their physical environment, these attention guidance techniques must not only compete with other virtual imagery, but also with distracting or attention-grabbing features in the user's physical environment. Because of the wide range of physical-virtual environments that pervasive AR users will find themselves in, it is difficult to design visual cues that “pop out” to the user without performing a visual analysis of the user's environment, and changing the appearance of the cue to stand out from its surroundings. In this paper, we present an initial investigation into the potential uses of dichoptic visual cues for optical see-through AR displays, specifically cues that involve having a difference in hue, saturation, or value between the user's eyes. These types of cues have been shown to be preattentively processed by the user when presented on other stereoscopic displays, and may also be an effective method of drawing user attention on optical see-through AR displays. We present two user studies: one that evaluates the saliency of dichoptic visual cues on optical see-through displays, and one that evaluates their subjective qualities. Our results suggest that hue-based dichoptic cues or “Forbidden Colors” may be particularly effective for these purposes, achieving significantly lower error rates in a pop out task compared to value-based and saturation-based cues.
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- Award ID(s):
- 1800961
- PAR ID:
- 10442385
- Date Published:
- Journal Name:
- IEEE Transactions on Visualization and Computer Graphics
- ISSN:
- 1077-2626
- Page Range / eLocation ID:
- 1 to 16
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1109/TVCG.2022.3195111
