Introduction Retinitis pigmentosa is an umbrella term for a group of diseases of the eye which in their course lead to destruction of the retina (retina). The retina is, so to speak, the visual layer of our eye, the destruction of which leads to loss of vision or blindness. The term “retinitis” is rather misleading, … Retinitis pigmentosa
What forms of retinitis pigmentosa are there? As already mentioned at the beginning, retinitis pigmentosa is basically a collective term for a variety of diseases in which similar processes occur. The classification is sometimes different in different works of technical literature, but basically one can distinguish between three groups of Retinitis pigmentosa: In addition to … What forms of retinitis pigmentosa are there? | Retinitis pigmentosa
Synonyms in a broader sense Medical: Achromatopsia, Achromasia Introduction With total color blindness, no colors at all can be perceived, only contrasts (i.e. light or dark). Often red-green blindness is also erroneously called color blindness, although it is a color blindness (color anomaly). A distinction is made between two forms: congenital color blindness and acquired … Color blindness
Symptoms The cones are not only important for color vision, but especially for sharp vision, since the retina contains only cones at the point of sharpest vision, the yellow spot, with which we usually fixate points. The rods do not offer by far the same resolution as the cones, but they are more sensitive to … Symptoms | Color blindness
How do you test children? In order to diagnose color blindness (achromasia) in children, tests can be used for examination from about the age of three years. However, the tests are not very different from those used for adults. A typical test is the Ishihara Color Chart. It is used to test whether the children … How do you test children? | Color blindness
Relevance for the driver’s license In fact, a color sense disorder rarely leads to a restriction of participation in traffic. Color-blind people are allowed to obtain a driver’s license and drive a car. Color blindness primarily comprises red-green vision deficiencies. Only a complete loss of color sense (achromatopsia) leads to restrictions. In this case there … Relevance for the driver’s license | Color blindness
Definition The human eye has two types of photoreceptors that enable us to see. On the one hand there are the rod receptors and on the other hand the cone receptors, which are subdivided again: blue, green and red receptors. These photoreceptors represent a layer of the retina and send a signal to the cells … Rods and cones in the eye
Function The photoreceptors of the human eye are used to detect incident light. The eye is sensitive to light rays with wavelengths between 400 and 750 nm. This corresponds to the colors from blue to green to red. Light rays below this spectrum are referred to as ultraviolet and above as infrared. Both are no … Function | Rods and cones in the eye
Tasks As described above, the cone receptors serve for daytime vision. Through the three types of cones (blue, red and green) and a process of additive color mixing, the colors we see can be seen. This process is different from physical, subtractive color mixing, which is the case, for example, when mixing painter’s colors. In … Tasks | Rods and cones in the eye
Distribution Due to their different tasks, the cones and rods in the eye are also distributed differently in their density. The cones serve for sharp vision with color differentiation during the day. They are therefore most common in the center of the retina (yellow spot – macula lutea) and are the only receptors present in … Distribution | Rods and cones in the eye
Yellow dot The macula lutea, also called the yellow dot, is the place on the retina with which people primarily see. It was named after the yellowish coloration of this spot when the back of the eye is mirrored. The yellow spot is the place on the retina with the most photoreceptors. Outside the macula, … Yellow dot | Rods and cones in the eye
Visual dye The human visual pigment consists of a glycoprotein called opsin and the so-called 11-cis-retinal, which is a chemical modification of vitamin A1. This is also the reason why vitamin A is so important for visual acuity. Severe deficiency symptoms can lead to night blindness and in extreme cases to blindness.Together with the 11-cis … Visual dye | Rods and cones in the eye
