Landolt Ring

**Landolt ring** is a special device that is used to study the functions of the human retina. It was invented in the 19th century by Swiss ophthalmologist Ernest Landolt. The device consists of a round metal plate, in the center of which there is a hole with a diameter of about 1 mm. Two lenses are attached to the ring - a small one and a large one - which are mounted on a tripod. The patient looks into a small lens through a hole in the ring, and the doctor observes the reaction of the eyeball. If the patient sees a point of light during the test, this means that the retinal function is normal, but if not, the doctor can diagnose various eye diseases. Today, this test is widely used in ophthalmology to diagnose glaucoma, retinal dystrophy and other diseases.

Landolt ring is a pattern used in ophthalmology to test patients' vision. It was invented in 1862 by Swiss ophthalmologist Eduard Landolt.

The Landolt ring is a circle divided into 24 sectors, each of which has its own color. The patient must name all the colors that he sees on the ring. If the patient cannot name all the colors on the ring, this may indicate a vision problem.

The Landolt ring is used to determine visual acuity, evaluate color vision, and check for the presence of cataracts. It is also used to diagnose visual impairment due to various diseases such as glaucoma, retinal detachment and others.

Using a Landolt ring is a simple and effective method of testing vision. It allows you to quickly and accurately determine visual acuity and identify possible visual impairments.