Search results for "Volumetric display"
showing 9 items of 9 documents
Impact of viewing distance on relative depth judgements for stimuli in physical space
2019
In natural viewing, numerous depth cues are available to the visual system, but their significance varies considerably depending on the viewing distance. How is it reflected in the outcome of depth judgements? We have designed a psychophysical experiment with a limited number of depth cues to examine distance-related changes in the correct response rate and time. Twenty young adults evaluated relative depth of stimuli in physical space. Each time four constant angular size achromatic stimuli were presented on a volumetric multi-planar display. One of these stimuli was demonstrated closer to the observer comparing to others. The experiment followed the four-interval forced-choice procedure. …
Focusing in Depth: Post-Task Accommodation Shifts After Sustained Near Work with Volumetric Multi-Planar Display
2018
Post-task refraction shifts were evaluated with eccentric photorefraction technique to better understand response of visual system and eye accommodation to sustained near work with 3D image formed by volumetric display.
Assessment of spatial perception for a multi-layer volumetric display: the effect of exocentric and egocentric distance on relative depth judgements
2020
Three-dimensional images on multiple depth layers of the volumetric display provide the physiological depth cues which ensure the high precision of depth judgements at close viewing distances and enhance the user experience. However, the contribution of physiological cues declines with an increase of viewing distance (egocentric distance), and the human spatial perception varies depending on the inter-stimuli distance (exocentric distance). We conducted a psychophysical experiment to test the perception of three-dimensional images rendered on the volumetric display depending on exocentric and egocentric stimuli distance. The constant angular size visual stimuli were displayed on different d…
Visual Search Performance Depending on Target-Distractor Difference on Volumetric Display and Flat Panel Display
2019
The search items were demonstrated on the volumetric display and flat panel display. In contrast to the correct response rate, the search time and number of interactions were considerably affected by the type of visualization.
Visual search in three-dimensional non-medical images: visual-motor performance of radiologists
2019
The visual search abilities of radiologists are systematically trained due to the specifics of their professional tasks. We investigated whether the visual-motor performance of radiologists, residents and students varied when searching non-medical targets on the volumetric display. As a result, no significant differences were found in the correct response rate among three groups. However, the total number of interactions was considerably higher for the resident radiologists and medical students comparing to the experienced radiologists. Our results suggest that the radiological experience does not interfere with the outcome in the developed visual search task, but may be reflected in motor …
EEG smadzeņu aktivitātes novērtējums trīs-dimensiju attēlu uztverē
2021
Darbs ir uzrakstīts angļu valodā uz 30 lapaspusēm. Tas satur 9 attēlus, 1 tabula un 26 atsauces uz literatūras avotiem. Tā kā trīsdimensiju tehnoloģijas strauji attīstās, pētījumos nepieciešams izvērtēt iekārtas un to mijiedarbību ar cilvēku. Pētījuma mērķis ir novērtēt uzvedības un neirofizioloģiskās iezīmes cilvēkiem, kuri veic uzdevumu izmantojot divas dažādas vizualizācijas: volumetrisko un stereoskopisko. Izmantojot elektroencefalogrāfiju tika reģistrēta smadzeņu aktivitāte un analizēti iegūtie potenciāli un neirālās svārstības. Spēcīgu dziļuma uztveres ietekmi ar abām vizualizācijas tehnoloģijām novēroja tikai vēlīnos uztveres procesos paura garozas reģionā. Turklāt ātrāks reakcijas l…
Smadzeņu aktivitāte un volumetriskais ekrāns
2020
Maģistra darbs uzrakstīts angļu valodā uz 32 lappusēm. Tas satur 15 attēlus un ir atsauces uz 37 literatūras avotiem. Strauji attīstoties trīsdimensiju (3D) vizualizācijas tehnoloģijai ir nepieciešams precīzi novērtēt cilvēka spēju pielāgoties tai. Šādos pētījumos plaši tiek izmantots EEG. Pētījuma mērķis bija izpētīt smadzeņu aktivitātes īslaicīgās izmaiņas, skatoties uz volumetriskiem attēliem un salīdzinot ar anaglifa 3D attēlu aplūkošanu. Uzdevums bija noteikt tuvāk esošo apli starp četriem projicētiem apļiem. Smadzeņu aktivitātes signālu reģistrēšanai tika izmantots EEG. Izsaukto potenciālu P300 komponentē darba slodzes ietekmē netika novērotas būtiskas izmaiņas. Būtiskas izmaiņas tika…
Ocular performance evaluation
2019
Real and virtual three-dimensional (3D) imaging has found useful applications across different areas of health sciences and with the current rapidly progressive development stage we can expect that the use of 3D imaging soon will be a part of a daily visual load for medical personnel. To better understand the possible impact of prolonged work with 3D content on eye accommodative response and pupil size we compared two 3D imaging techniques - volumetric display that is real voxel-based system and anaglyph technique that is virtual pixel-based system. We have investigated accommodative lag and pupil responses in 38 emmetropic young adult after prolonged visual task with volumetric 3D display …
Comparative assessment of brain activity during depth perception of stereoscopic and volumetric images
2020
Recent advancements in visualization systems have triggered a growing demand for the objective and accurate comparison of user cognitive requirements when perceiving three-dimensional images demonstrated in different ways. In this work, we present the first comparative assessment of brain activity in subjects viewing stereoscopic images and volumetric images. Electroencephalography was employed to assess the short-term changes in event related potentials and neural oscillations which were further interpreted in terms of cognitive requirements for relative depth judgments. As a result, considerably higher activity have been registered in the beta band and gamma band in case of judging relati…