Description
The Lang Stereotest was created to simplify stereopsis screening in children. It is based on two principles: random dots and cylindrical gratings. Lang Stereotest II measures disparities: Moon and Star are 200, car 400 and elephant 600 seconds of arc plus monocularly visible star. In the new Lang II test, the random dots are smaller and less dense. This disparity is finer, namely 200 seconds of arc for the moon and the star, 400 for the car, and 600 for the elephant when viewed at a distance of 40cm. The monocularly visible star helps attract and maintain the interest of small children. It also gives the patient without binocular vision the satisfaction of having seen something at all.