Bifocals are special multi-focal glasses. They are suitable for people who have two refractive errors. What are bifocals? Bifocals eliminate the need to switch between distance and reading glasses. With the help of bifocals, two different refractive errors can be corrected at the same time. The Latin term ‘bifocal’ means ‘two’ (‘bi’) and ‘focal point’ … Bifocals: Applications & Health Benefits
Secondary directions are always oriented to a main direction (fixation). They differ from each other by respectively different spatial values and are significant for the emergence of the spatial sense. A rearrangement of the secondary directions always causes a change in the perception in space. What is the secondary direction? A secondary sense of direction … Secondary Direction: Function, Tasks, Role & Diseases
The first process of perception is sensation at the sensory cells of the perceptual structures. To the recognition of a perception, a comparison is made in the brain between currently perceived stimuli and stimuli from the perceptual memory. Only this matching enables the human being to interpret. What is recognition? Recognition takes place on the … Recognize: Function, Task & Diseases
The pupillometer is a pupillometry instrument that determines the width and light responsiveness of the pupils. Pupillometers are especially important before eye refractive surgery because they can determine the laser range on the cornea. Because pupil width is also relevant from neurological and psychological perspectives, pupillometry also helps these disciplines. What is a pupillometer? A … Pupillometer: Application & Health Benefits
An ocular prosthesis is an artificial eye. It is used as a cosmetic replacement for a lost eye. What is an ocular prosthesis? In Germany, eye prostheses have existed since the 19th century, and their manufacture is purely manual. An ocular prosthesis is understood to be an artificial eye. It is also commonly known as … Ocular Prosthesis: Applications & Health Benefits
In acoustics, localization is the recognition of the direction from which a sound comes in three-dimensional space and the recognition of the distance of the sound source. Localization is based on directional hearing with both ears (binaural) and distance hearing, which is also possible by hearing with one ear (monaural). Localization is a passive process … Localization: Function, Tasks, Role & Diseases
What are the characteristics of medical safety glasses, what distinguishes them from occupational safety glasses? Are there different forms of medical safety glasses? What is the structure of medical safety glasses? What are their benefits? This article deals with all these questions. What is medical safety eyewear? Medical safety glasses are used to protect the … Medical Safety Goggles: Applications & Health Benefits
Magnifiers are not only used for reading, but also in personal care and medicine. There are different types of magnifiers, which are used differently, depending on the area of application. They are primarily used to better detect possible changes or help to work more precisely by seeing in greater detail. What is a magnifying glass? … Magnifying Glass: Applications & Health Benefits
The autokinetic effect corresponds to an optical illusion. When a static light stimulus is delivered in an otherwise monochromatically dark environment, humans lack reference points for judging the localization and motion of the light spot. This creates the impression that the static stimulus is moving in the environment. What is the autokinetic effect? Human visual … Autokinetic Effect: Function, Tasks, Role & Diseases
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
