Assessing Stereo Blindness and Stereo Acuity on Digital Displays

Previous studies on stereoscopic acuity have shown that the percentage of stereo blind subjects is relevant. Moreover, stereoscopic visualization is becoming widely diffused in different fields, like e.g., entertainment, surgery or VR training, where it is necessary an accurate assessment of stereoscopic abilities of the involved subjects. Therefore, there might be the need of performing a stereo blindness and stereo acuity test before each visualization session involving stereoscopic images.
We propose the D_SA method to assess stereo acuity directly on the chosen device, under the same visualization condition and setup adopted for the tasks to perform, in order to have the same perceptual response. The method consists in a sequence of 10 images with a fixed background (a white noise random-dots pattern), and three squares in the foreground. In each image, one of the three squares is randomly presented with varying disparity values, while the others are presented at zero parallax. The considered disparities are 160, 100, 63, 50, 40, 32, 26, 20, 16 and 12.5 seconds of arc.
In each image, the subject must report which square is perceived in front of the others.

A subject during D_SAT stereo acuity assessment

The D_SA test is suitable for a wide range of stereoscopic displays: please fill the following form to download the images matching the resolution and dimension of your display. You will be provided also with indications regarding the viewing distance to set for each tested disparity. To ensure reliability of D_SA test, it is important to perform the assessment using the correct set of images at the correspondent viewing distance.