Lang stereoacuity test does not require glasses and relies on what to create retinal disparity?

Lang stereoacuity test does not require glasses and relies on what to create retinal disparity?

• A. It uses red-green filters
• B. It requires polarized lenses
• C. It uses random dot patterns
• D. Does not require glasses and uses ridged disparity

Answer: (D)

Stereo tests can measure depth perception without any eyewear by using images that embed disparity directly in their shapes. The Lang stereoacuity test does this with ridged, contour-based pictures: the raised, ridge-like features create subtle horizontal disparities that the brain fuses into a sense of depth, even though both eyes view the same image. Because the depth cues come from the pattern itself and don’t require separating the images for each eye, no glasses are needed. This is different from tests that rely on red-green or polarized glasses to split what each eye sees, or from tests that use random-dot patterns which need special viewing aids to reveal disparity.

Stereo tests can measure depth perception without any eyewear by using images that embed disparity directly in their shapes. The Lang stereoacuity test does this with ridged, contour-based pictures: the raised, ridge-like features create subtle horizontal disparities that the brain fuses into a sense of depth, even though both eyes view the same image. Because the depth cues come from the pattern itself and don’t require separating the images for each eye, no glasses are needed. This is different from tests that rely on red-green or polarized glasses to split what each eye sees, or from tests that use random-dot patterns which need special viewing aids to reveal disparity.