Abstract
In order to investigate depth perception in the situations, in which real objects and virtual objects coexist (i.e., Mixed Reality), we examine depth perception of the real objects and the virtual objects when they are presented at the same depth defined by binocular retinal disparity. Experiment was conducted in a lit room. A white plate (16 cm of width, 16 cm of height) was located in front of an observer whose head was fixed by a chinrest. The observation distance was 90, 100, or 110 cm. (The distance to the plate defined by binocular retinal disparity was the same as the observation distance.) A virtual object was generated with a workstation. A stereogram was displayed on a rear projection screen (81 cm of width, 61 cm of height) with a DLP projector. The image for the left eye and that for the right eye appeared alternatively with 120 Hz of temporal frequency, and were given to the suitable eyes with a pair of LCD shutter glasses. The screen was located to the left of the observer. By placing a beam splitter (20 cm of width, 20 cm of height) in front of the observer, the stereogram was projected onto the observer's eyes. The distance from the observer to the screen via the beam splitter was 100 cm. A white rectangle (17 cm of width on the screen, 13 cm of height on the screen) was presented to the left of the plate. The distance to the rectangle defined by binocular retinal disparity was 90, 100, or 110 cm. The observers estimated the amount of depth between the plate and the rectangle. The results showed that the rectangle was perceived slightly closer than the plate when they were presented at the same distance defined by binocular retinal disparity.
The authors are grateful to Hitoshi Sakai who helped to make the apparatus.