Depth Perception in Vision Testing

Depth perception is the ability of the eye to tell the distance between objects, also known as stereopsis. There are two standard tests that optometrists use to determine if your depth perception is adequate.

Titmus Fly Stereotest

• The Titmus Fly Stereotest is a three-dimensional image of a fly in which the wings appear to be sitting closer to the viewer. Some tests also use a butterfly or other winged bug. Optometrists often use this test on young children by asking them to try to grab the wings.

Random Dot Stereotest

• A random dot stereotest, also called a Frisby Stereotest or Lang Stereotest, uses a sheet of dots in which one or more of the dots appears to stand out from the others. The optometrists asks the patient to point out which dot appears closer.

Test Results

• Depth perception tests are often used in young children to determine if both eyes have strong vision or if the child might have vision problems in the future. If depth perception is determined to be substandard, there are therapies and exercises that can improve it.