Abstract
In the volumetric display, multiple planes with light scattering properties can be used to generate three-dimensional images with real volume. This structure of optical element is known to be facilitating depth perception, but at the same time limiting the maximum achievable luminance (Osmanis et al., 2018). Our study has aimed to test whether the structure of optical element affects brightness perception of the maximum luminance stimuli when demonstrated on different depth planes of the volumetric display.
Fifteen young participants with normal vision matched brightness of 6 deg × 6 deg stimuli presented on two displays in accord with the adaptive psychophysical procedure. The participant's task was to compare the brightness of the stimulus on the flat panel display (Samsung Electronics, S24C650) to the one on the volumetric display (LightSpace Technologies, ×1405). The uniform background was ensured by covering the rest of monitors with dark coverage. Both displays were characterized using a Photo Research SpectraScan PR-655 spectroradiometer.
RGB to luminance conversion using gamma function approximation was employed to analyse the results of the psychophysical test. Overall, the average threshold appeared to be independent of stimuli demonstration in varying depth of the optical element, however, significant variation was present among participants. Mostly, the obtained results were slightly lower comparing with the actual luminance of stimuli on different planes (no significant difference was reached). Altogether, these findings indicate that users can perceive the maximum luminance visual stimulus on different depth planes of the volumetric display as equally bright.
The research has been funded by the University of Latvia and LightSpace Technologies Inc., the donation of SIA Miktotikls and the Foundation of the University of Latvia (the project No. 2184).