What tests are available for the blind spot?
The blind spot is usually not noticed in everyday life due to a compensatory reaction of the body. However, it can be made visible by a simple test. To do this, an X and an O are written on a white sheet of paper at a distance of about 10 cm from each other. If you now cover your right eye and fix the right letter at a distance of about 30 cm, the left letter disappears. If you keep your left eye closed, the right letter disappears.
What is the difference between blind spot and yellow spot?
The yellow spot is also called macula lutea. This is a special area on the retina through which the visual axis runs. The visual axis means that this is where the point with the greatest density of cones, the colour-sensitive sensory cells, is located.
When fixing an object to the eye, the eye automatically bundles incident light rays in such a way that they always hit the exact spot of the yellow spot. As a result, this point is also responsible for focusing on the surroundings. The size is about 3-5 mm.
It is called a yellow spot because it appears yellow when the background of the eye is reflected. The colour is caused by pigments (lutein) stored there. The blind spot practically lacks a piece of the retina, which means that no visual performance is achieved here. It is therefore exactly the opposite of the yellow spot, where the centre of vision with the point of sharpest vision is located and where the finest spatial perception takes place.
History
The blind spot was already discovered in 1660 by the French physicist and clergyman Edme Mariotte.
