Recognition of stereoscopic images among elderly people

We tested 130 subjects including elderly people using two types of stereogram. One was a 3D image of a repeating parallel pattern showing balloons, from a software program called Stretch Eye. This program adopts a shift method in which the balloons diverge just at the point that causes a single shift between the right and left eyes, so that they appear to be more distant than the monitor screen. The Stretch Eye image was shown on a color LCD. The other image was a paper stereogram. Both used the same image of balloons. Using these 2 types of 3D image, we analyzed the recognition of stereoscopic images among elderly people. The subjects were 130 people aged 18 to 86 years, including 60 people over 60 years of age. The subjects' visual functions of cataract cloudiness (CC) and pupil distance were measured. Comparisons were carried out for the two targets of the paper stereograms and color LCDs. Subjects were divided into four groups according to the severity of CC. Two-way ANOVA was used for the statistical analysis in order to compare the influence of the target types, age and cataract cloudiness on the ability, distance and time of stereoscopic recognition. In a two-way ANOVA, two kinds of dependant variables, recognized speed (RS) and recognized distance (RD) were used for the subjects' stereoscopic recognition performance.