Conflicting ordinal and metric depth information interferes with depth matching

Area of Science:

• Visual perception
• Augmented reality
• Depth perception

Background:

• Depth perception relies on multiple visual cues.
• Conflicting cues can lead to perceptual distortions.
• Augmented reality (AR) presents unique challenges for depth perception.

Purpose of the Study:

• To investigate how conflicting metric (binocular disparity) and ordinal (occlusion) depth information affect perceived depth in AR.
• To quantify the impact of occlusion on distance estimation.
• To model the observed perceptual effects using a Bayesian framework.

Main Methods:

• Virtual letter 'A' presented via HoloLens 2 AR display superimposed on occluding surfaces with variable transparency.
• Observers performed depth matching tasks with and without occluders.
• Retinal size cues were manipulated to assess their influence.

Main Results:

• Accurate depth localization when the virtual letter was in front of the occluder or no occluder was present.
• Systematic underestimation of distance when the virtual letter was rendered behind the occluder.
• Underestimation magnitude correlated with occluder opacity and persisted despite retinal size cues.

Conclusions:

• Incorrect occlusion arrangements strongly influence perceived depth in AR.
• Perceived depth is distorted even when binocular disparity is available.
• A Bayesian cue combination model with specific priors accurately predicts the observed distance underestimation.