Which are better optologists or opticians


When it comes to “stereo”, most people think of music first and foremost: In order to create a spatial sound impression, at least two or more speakers are required. The same applies to stereo vision. To one spatial visual impression production requires two or more eyes - most living beings need two. (The New Zealand bridge lizard has a third eye on its head, by means of which it can perceive light-dark differences, but this special equipment makes it an exotic one, at least on this planet.)

However, it is not just the number of eyes that is decisive for the quality of spatial vision. It is crucial that the two eyes approximate the brain equivalent visual impressions deliver.

If this is the case and the retinas of both eyes receive images of the environment that differ only slightly from one another due to the distance between the eyes, the brain can do both Fuse retinal images. The result is a single image of the environment that has a spatial dimension.

How does stereo vision work?

When fixing an object, each eye takes a slightly different angle. The closer the object is, the stronger the inward movement of the eyes towards the nose (convergence) must be. The motor coordinationis done by the eye muscles that sit on the outside of the eyeball and control its alignment. This is already learned in childhood. If this learning process is disturbed, however, this can lead to considerable impairment of spatial vision.

Disturbances in stereo vision

If the eyes of a child have different degrees of ametropia (anisometropia), the brain receives two images of different quality that it can no longer fuse. That's why they are early detection an ametropia and its optical correction are very important. As a rule, the correction is carried out using glasses, but contact lenses may be the better means, especially in the case of higher anisometropia. In contrast to glasses, they do not lead to differently sized retinal images (aniseikonia), which in turn make stereo vision more difficult if the ametropia of the eyes deviates significantly from one another.

At a Squint error three-dimensional vision is also often not possible because the visual impression of the cross-eyed eye is suppressed. Here one can Prism glasses help: The rays are specifically deflected in such a way that, despite the squint, two retinal images of equal quality can be created.

The Time window for such optical interventions, however, is limited. The visual process can be easily restored up to the age of six, up to the age of ten it’s getting more difficult. After that the development is finished.

Test of stereo vision

As part of the determination of the spectacle lens by the optician, stereo vision is usually also checked. You can find out more about lens determination at www.optometrist.de.


  • Stereo vision is the highest form of binocular vision.
  • Due to the distance between the two eyes, slightly different images of a fixed object are created on the respective retinas.
  • The brain determines an impression of the spatial depth from the comparison of the two retinal images.
  • Put simply, stereo vision is synonymous with 3D vision.