The Lang-Stereotest® II-R is a revised version of the Lang-Stereotest® II. This revised version has improved optical and printing quality compared to the previous version and, when used correctly, shows no monocular clues. Also new is a brief instruction manual in English on the back of the test card, with a schematic diagram for correct use, a mirror-image arrangement of the stereo objects, and typical eye movement patterns in stereopositive subjects.
The Lang-Stereotest® II-R is a supplement to the proven Lang-Stereotest® I-R (Star, Cat, Car) and is also used to test binocular vision according to the same principle. In addition to three figures visible only binocularly (crescent moon, car, and elephant), it also features a contoured star visible to monocular vision. Many users requested another stereoscopic examination card as an alternative to the Lang-Stereotest® I-R. In the Lang Stereotest II-R, the random dots are smaller and less dense. The disparities are somewhat finer: 200 arcseconds for the moon, 400 for the car, and 600 for the elephant, for an observation distance of 40 cm (10-15 inches). The monocularly visible star with a disparity of 200 is intended to improve diagnostics in young children by increasing attention and reaction. Furthermore, subjects without binocular vision are less disappointed.
