Astigmatism is a deformation of cornea which is the reason why light does not focus on one point of the retina. You can see it as a distortion or blurness of a text or an object's image. You are always checked for astigmatism in an eye examination and it is corrected if necessary with a suitable spectacle lens. The surface of an astigmatic eye is different in different directions and so is the need for the optical strength of the lens. In this case the lenses are ground cylindrical (shortened syl or cyl or c.) which means that the lenses have two different strengths (e.g. in vertical and horizontal direction) and the strength of the lenses is shown for example this way: sf +1,0 cyl -0,25 ax 90°.
Eyesight has weakened if, for instance, watching TV or reading a text has become difficult or you do not see traffic signs or bus numbers well. Headaches can also be a sign of a weakened eyesight, especially if they appear at the end of the day or after a lot of intensive near vision work.
The result of the eye examination will be the knowledge of your refraction according to which the far vision strength is determined. The checkup will also show if you have astigmatism and the need to correct it. Far vision strength is the basis for a possible need to prescribe near vision spectacles, the close add for which is shown separately.
The size of the close add is affected by your usual working range and the adaptability of your eyes to see at a closer distance. The need for the close add changes with age. The overview of the eye examination also shows the sharpness of your vision with spectacles and without.
The elasticity of the eye lens deteriorates with age – you notice this when reading as the text gets hazy. Reading spectacles with necessary strength help to make the text clear again.
Vision is the reflection of the visible object on the retina of the fundus of the eye. Light rays entering the eye are focused by the cornea and lens to form an image on the retina. The retina contains millions of light-sensitive cells which convert the image into a pattern of nerve impulses. These impulses are transmitted along the optic nerve to the brain. Information from the two optic nerves is processed in the brain to produce a single coordinated image.
Eyes should be examined at least once in two years. Eye examination is a simple and quick procedure at Instrumentarium stores. In addition to the eyesight, our optometrists also take care of the wellbeing of your eyes. If necessary, we will make an appointment with an ophthalmologist for you. It is advisable to visit an ophthalmologist at the age of 40 at the latest and then once in every 3 years.
During the eye examination different tests are performed depending on how you see and which spectacles or contact lenses you will probably need to correct your eyesight.
Eye examination determines how well you see with your eyes and to what extent spectacles improve the eyesight. First of all, eye refraction is checked which determines the strength of far vision spectacles. Then your near vision ability is tested.
The eye examination takes about 15-30 minutes.