Contact lenses, like eyeglasses, belong to the visual aids and correct visual defects. They are placed with the help of the fingertips on the eye or on the tear film on it and can thus compensate for all common refractive errors. Wearing glasses can be avoided in this way, which also gives contact lenses a … Contact Lenses: Applications & Health Benefits
Definition Visual acuity (visual acuity, visual acuity, minimum separable) indicates the measurable degree of ability to recognize patterns and contours in the outside world as such. Minimum visibile Minimum visibile is the limit of visibility. This is reached when objects that are viewed and imaged on the retina can no longer be distinguished as contour … The visual acuity
Physiology of visual acuity Human visual acuity depends on several sizes: Physically the size of the pupil limits the resolution of the eyeball, physiologically the resolution is determined by the density of the receptors (rods and cones) and the signal processing of the receptive fields of the retina. The resolution reaches its maximum value when … Physiology of visual acuity | The visual acuity
The optic nerve is formed by approximately one million nerve fibers. These nerve fibers are grouped into bundles and meet about 10 to 15 millimeters behind the eyeball with the central artery of the retina and the vein. Together, the vessels then move forward in the interior of the nerves to the optic nerve head … Causes of optic atrophy
Many people need to wear glasses. A congenital visual impairment, advancing age or intensive work on the computer are most of the reasons for having to wear glasses. While the visual aid used to be a necessary evil, modern glasses today definitely add striking accents to the wearer’s face. What is a pair of glasses? … Glasses: Applications & Health Benefits
Introduction Nearly everyone can recognize small black dots, fluff or threads when they look at a white wall, the sky or white paper, which other people present cannot see. These spots in the field of vision move flittingly together with the line of sight. They are called “flying mosquitoes” (Mouches volantes). They are caused by … Vitreous body turbidity
As early as around the year 1000, an Arab scholar came up with the idea of supporting the eye by means of optical lenses. Around 1240, monks put this idea into practice – the birth of eyeglasses. For centuries, they were the only way to correct defective vision. But in recent years, they have had … Eye Laser and Other Modern Methods
Risks and complications The most frequent complication after Lasik surgery manifests itself in the form of dry eyes. This disorder manifests itself as a deterioration of vision, but a feeling of dryness tends to recede into the background. This is due to the destruction of the nerve fibers supplying the cornea (denervation) during Lasik surgery. … Complications with Lasik
If you have blurred vision both at a distance and at close range, the cause may be a so-called astigmatism. The eye is no longer able to focus the incident light on an exact point on the retina and thus to bring it into focus, but the affected persons see points as blurred lines. Normally, … Astigmatism: Blurred Vision
Symptoms The symptoms of astigmatism (astigmatism, astigmatism) depend on the severity of the curvature of the cornea, since this results in refractive errors of varying degrees. A slight astigmatism is often not noticed by those affected. However, if the astigmatism is more pronounced, the clear astigmatism is noticeable due to blurred vision at near and … Symptoms | Astigmatism: Blurred Vision
History While regular astigmatism (astigmatism, astigmatism) does not normally change over the course of life, irregular astigmatism can progress steadily. This is especially the case when there is a permanent malformation of the cornea, in which the center of the cornea grows conically forward (so-called keratoconus). If the astigmatism is not corrected, severe headaches must … History | Astigmatism: Blurred Vision
Glasses are a visual aid that consists of a frame and two individual lenses. With the help of glasses or reading glasses, a certain refractive error such as farsightedness, shortsightedness or astigmatism can be corrected in a simple way. What are reading glasses? Reading glasses are mostly used to correct presbyopia. However, more and more … Reading Glasses: Applications & Health Benefits
