Enhancing visual inspection with binocular rivalry: Integrating three studies

The phenomenon of binocular rivalry occurs in stereoscopic viewing where the images presented to the two eyes contain small areas which resist stereoscopic fusion. In industrial inspection, this could help locate defects if a perfect item is presented to one eye and a potentially-defective item to the other eye. Any defect will show a sparkling visual effect. A sequence of three circuit board inspection experiments was used to determine whether this system is practical. An initial experiment using board images showed only a small effect of binocular fusion. A second experiment using symbol stimuli with excellent registration showed binocular rivalry to increase performance considerably, and to remove any effect of inspecting for multiple defects simultaneously. The third experiment returned to realistic inspected items, but ensured good registration by placing images on a computer screen. This experiment again showed the superiority of binocular rivalry, and also no unusual visual strain from stereo viewing. These experiments allow us to delineate the conditions under which the benefits of binocular rivalry can be exploited in quality control practice.