Effect of the field of view and semantic content of the stimulus on accommodation stimulated with a volumetric Badal optometer

The capability of the human eye to focus near targets is the so-called concept of Accommodation. This concept has been comprehensively studied since the last century, however, there are still many issues related to it that are not fully clear. Additionally, since the apparition of virtual reality (VR) technologies accommodation has been given an increasing relevance since it is thought to be one of the key points for the success in VR development and implementation. In other words, an appropriate representation of focus cues (i.e., accommodation and peripheral depth cues) i Purpose: To investigate the effects of different field of view (FOV) and semantic content of the stimulus on accommodation stimulated with a volumetric Badal optometer and to compare these results with natural-viewing condition. Methods: Accommodation was objectively measured with the PowerRef II at 0.17 and 5.00 D of accommodation stimulation (AS) on 17 young healthy patients. For both Badal targets and real free space targets (natural-viewing condition), at each AS, the FOV was discretely changed from 10º to 30º (10º-step). The volumetric system comprised the fixation stimulus and two fix planes at 0.17 D and 5.00D where besides the central stimulus, there are peripheral stimulus. Results: The accommodative response obtained in a volumetric Badal system is more lead at far distance and more lagged at near distance than the natural-viewing condition. However, the repeated measures ANOVA did not show significant statistical differences among all the configurations at both far and near distance (p>0.05). Conclusions: Accommodation stimulated in a volumetric Badal system is clinically comparable to accommodation stimulated using real targets in free space. Accommodation is not significantly affected by the semantic content of the scene nor the size of the field of view in a volumetric Badal system.