Display technologies in the fields of virtual and augmented reality affect the appearance of human representations, such as avatars used in telepresence or entertainment applications, based on the user’s current viewing conditions. With changing viewing conditions, it is possible that the perceived appearance of one’s avatar changes in an unexpected or undesired manner, which may change user behavior towards these avatars and cause frustration in using the AR display. In this paper, we describe a user study (N=20) where participants saw themselves in a mirror standing next to their own avatar through use of a HoloLens 2 optical see-through head-mounted display. Participants were tasked to match their avatar’s appearance to their own under two environment lighting conditions (200 lux and 2,000 lux). Our results showed that the intensity of environment lighting had a significant effect on participants selected skin colors for their avatars, where participants with dark skin colors tended to make their avatar’s skin color lighter, nearly to the level of participants with light skin color. Further, in particular female participants made their avatar’s hair color darker for the lighter environment lighting condition. We discuss our results with a view on technological limitations and effects on the diversity of avatar representations on optical see-through displays.
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Adjusting Transparency Toward Optimizing Face Appearance in Optical See-Through Augmented Reality
Augmented reality (AR) combines elements of the real world with additional virtual content, creating a blended viewing environment. Optical see-through AR (OST-AR) accomplishes this by using a transparent beam splitter to overlay virtual elements over a user’s view of the real world. However, the inherent see-through nature of OST-AR carries challenges for color appearance, especially around the appearance of darker and less chromatic objects. When displaying human faces—a promising application of AR technology—these challenges disproportionately affect darker skin tones, making them appear more transparent than lighter skin tones. Still, some transparency in the rendered object may not be entirely negative; people’s evaluations of transparency when interacting with other humans in AR-mediated modalities are not yet fully understood. In this work, two psychophysical experiments were conducted to assess how people evaluate OST-AR transparency across several characteristics including different skin tones, object types, lighting conditions, and display types. The results provide a scale of perceived transparency allowing comparisons to transparency for conventional emissive displays. The results also demonstrate how AR transparency impacts perceptions of object preference and fit within the environment. These results reveal several areas with need for further attention, particularly regarding darker skin tones, lighter ambient lighting, and displaying human faces more generally. This work may be useful in guiding the development of OST-AR technology, and emphasizes the importance of AR design goals, perception of human faces, and optimizing visual appearance in extended reality systems.
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- Award ID(s):
- 1942755
- PAR ID:
- 10615806
- Editor(s):
- Rogowitz, Bernice E; Pappas, Thrasyvoulos N
- Publisher / Repository:
- Society for Imaging Science and Technology
- Date Published:
- Journal Name:
- Journal of Perceptual Imaging
- Volume:
- 7
- Issue:
- 0
- ISSN:
- 2575-8144
- Page Range / eLocation ID:
- 1 to 12
- Subject(s) / Keyword(s):
- augmented reality optical see-through AR transparency perception faces
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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