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Auteur Gang Luo
Documents disponibles écrits par cet auteur
Ajouter le résultat dans votre panier Affiner la rechercheEffects of Perceptual-motor Training on Collision Judgments with Peripheral Prism Expanded Vision / Kevin E. Houston in OVS : Optometry & Vision Science, vol. 99, 12 (Décembre 2022)
[article]
in OVS : Optometry & Vision Science > vol. 99, 12 (Décembre 2022)
Titre : Effects of Perceptual-motor Training on Collision Judgments with Peripheral Prism Expanded Vision Type de document : article de périodique Auteurs : Kevin E. Houston ; Eli Peli ; Gang Luo ; Alex R. Bowers ; Russell L. Woods Année de publication : 2022 Langues : Français (fre) Descripteurs (mots clés) : [Thésaurus Mesh]:H:Hémianopsie:Hémianopsie / thérapie
[Thésaurus Mesh]Hémianopsie
[Thésaurus Mesh]Orthoptie
[Thésaurus HELB]:Optique:PrismeRésumé : SIGNIFICANCE: Peripheral prisms (p-prisms) improve blind-side detection of hazards in hemianopia by shifting the image of the hazard into the intact visual field. Collision judgments can be made accurately after detection by using a gaze shift to fixate the hazard in the prism-free portion of the lens, but this is slow relative to normal peripheral vision. A prior study found that prism adaptation for visual direction did not occur with general wear. We developed a perceptual-motor training regimen that resulted in accurate pointing at p-prism targets after six 1-hour sessions. PURPOSE: This study aimed to determine if improvements in pointing accuracy from perceptual-motor training generalized to collision judgments during simulated walking. METHODS: Participants with hemianopia (n = 13) made collision judgments in virtual reality for a person appearing 0.4 to 13.5° from the walking path. Judgments were measured under fixed gaze, requiring collision judgments via the p-prism image only, and free gaze, representing a more natural scenario. Measurements were made without and with p-prisms immediately after fitting, after a 2-week acclimation, after training, and 3 months later. Controls (n = 13) did one visit without p-prisms. RESULTS: Controls had 100% detection and symmetrically distributed collision judgments for the central 33 and 36% of hazards under fixed gaze and free gaze, respectively. In hemianopia, the seeing side was not different from controls. Blind-side detection was reduced without p-prisms to 40% fixed gaze and 82% free gaze and improved with p-prisms to 99% fixed gaze and 97% free gaze (P < .001). When first worn, fixed-gaze prism side collisions were 63 versus 37% on the seeing side and 41 versus 39% for free gaze (P < .001). There was a small improvement for fixed gaze after the 2-week acclimation (53%, P < .001), but no improvements from training or an additional 3 months of use. CONCLUSIONS: P-prisms improved detection, but collision judgments were inaccurate when seen only via the p-prisms and did not improve with perceptual-motor training. Patients should continue to be advised to turn their head and eyes to fixate the hazard after detection. Permalink : https://bibliotheque.helb-prigogine.be/opac_css/index.php?lvl=notice_display&id= [article]Exemplaires
Cote Support Localisation Section Disponibilité aucun exemplaire Measuring Virtual Reality Headset Resolution and Field of View: Implications for Vision Care Applications / Marissa Howard Lynn in OVS : Optometry & Vision Science, vol. 97, 08 (Aout 2020)
[article]
in OVS : Optometry & Vision Science > vol. 97, 08 (Aout 2020)
Titre : Measuring Virtual Reality Headset Resolution and Field of View: Implications for Vision Care Applications Type de document : article de périodique Auteurs : Marissa Howard Lynn ; Gang Luo ; Matteo Tomasi ; Shrinivas Pundlik ; Kevin E. Houston Année de publication : 2020 Langues : Français (fre) Descripteurs (mots clés) : [Thésaurus HELB]:Cinématographie:casque de réalité virtuelle
[Thésaurus HELB]:Optique:basse vision
[Thésaurus Mesh]Champs visuels
[Thésaurus Mesh]Collecte de données
[Thésaurus Mesh]Poids et mesures
[Thésaurus Mesh]Tests de vision
[Thésaurus Mesh]Thérapeutique
[Thésaurus Mesh]Troubles de la visionRésumé : SIGNIFICANCE: To judge the feasibility of virtual reality (VR) headsets for vision testing and treatment of binocular
vision disorders and low vision, angular resolution (logMAR) and field of view must be known and may not be reliably provided. This is the first study to measure the limitations of VR systems for eye care applications.
PURPOSE: This study aimed to measure, in a sample of VR headsets, eye-to-screen distance and other physical
and optical characteristics needed to calculate minimum angular resolution in logMAR and field of view in determining feasibility for vision applications.
METHODS: Eye-to-screen distance was measured, and logMAR, field of view, and maximum convergence demand
were calculated for two standalone VR devices, Oculus Rift DK2 and HTC Vive, and, for four smartphone VR headsets, Zeiss VR1, Samsung Gear VR, VR Box, and SunnyPeak, each paired with four high-resolution smartphones,
Samsung Galaxy S7/S8, iPhone X, and LG VR30.
RESULTS: On average, the smallest letter that could be displayed in VR was 0.41 ± 0.09 (20/51), ranging from
0.59 (20/78) in the DK2 to 0.28 (20/39) in VR Box with S7. Mean field of view was 50.2 ± 4.8°, ranging from
39.6° in the VR Box with S7 to 55° in the HTC Vive. The mean field of view when used as a low vision aid was
23.0° and 12.7° for 2.2 and 4, respectively. The mean maximum near convergence demand produced for a
60-mm interpupillary distance was 38.6 ± 10.1Δ.
CONCLUSIONS: The minimum angular resolution in logMAR of current VR technology is insufficient for visual acuity
testing and may be insufficient for standalone treatment of amblyopia. Field of view during movie watching or gaming
is about half that reported by manufacturers but adequate for some types of visual field testing. Use for vergence testing and training is a concern for headsets with long eye-to-screen distance or interpupillary distances <60 mm.Permalink : https://bibliotheque.helb-prigogine.be/opac_css/index.php?lvl=notice_display&id= [article]Exemplaires
Cote Support Localisation Section Disponibilité aucun exemplaire