The stereo test LANG 1 is User for testing 3D vision without polarized glasses.

This test was invented by the Swiss eye doctor Joseph Lang, and it is used for testing the stereo vision. The Chart has the size of a postcard and shows three pictures with different disparities from 1.200, 600 and 550 arch seconds. The LANG 1 test (as well as LANG 2) is a quick screening method for 3D vision, also to distinguish pseudo strabism from real strabism.

Special surface (no polarized glasses needed)

Postcard sized chart with 3 images

Test images with 1200, 600 and 550 arch seconds

The stereo test LANG 2 (Art.-Nr.: 81175) has a a fourth image (star), that can be seen without stereo vision.