OKO - Eye chart

An eye chart is a diagnostic tool used by ophthalmologists and optometrists to assess a patient's visual acuity. There are advanced electronic eye charts and standard paper charts that contain various combinations of letters, numbers, or other symbols in different sizes and levels of detail.

During the eye test, the patient is asked to read or recognize symbols on the chart from a certain distance. This test allows the ophthalmologist to assess the patient's ability to read or recognize certain letters or symbols. The result of the test is expressed in terms of a coefficient that determines visual acuity.

Eye charts are used in a variety of contexts, including during standard eye examinations, during vision screening, and to monitor the progress of treatment or correction of vision problems with eyeglasses or contact lenses. The best known ophthalmic chart is the Snellen chart, but there are many other variations, including children's charts, "E" shaped charts (Snellen hooks), and charts with symbols for patients who do not know the alphabet.

Hermann Snellen, a Dutch ophthalmologist, introduced his eye test in 1862, and his method is still used today. He created special vision test boards on which optotypes of different sizes are placed. The symbols allow one to determine visual acuity at a certain distance. Acuity is measured by the ratio of the distance from which the patient can see the optotype to the distance from which it should be visible. It is also worth noting that the Snellen test appeared 10 years before the optometrist Ferdinand Monoyer introduced the concept of diop

It is also interesting to note that the optotypes developed by Snellen are commonly used on road signs, advertisements and outdoor signs, where the size of the symbols is adjusted to the distance from which they should be read. It's a simple yet effective way to test and measure visual acuity.

While the classic eye chart contains standard letters, numbers or symbols in various sizes and levels of detail, the "OKO" eye chart offers a greater variety of optotypes and allows for quick optotype changes, which can be useful for examinations for different age groups or specific patient needs. In addition, the Meden-Inmed eye chart is equipped with a modern light source - light-emitting diodes (LEDs).