Can you have regular contacts with astigmatism

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Nerves, senses and hormones Curvature of the cornea also leads to ametropia. In so-called astigmatism (curvature of the cornea), the cornea has irregularities, which means that the images appear distorted. Glasses or contact lenses also help with astigmatism. Diseases of the eye: cataracts and glaucoma Age-related, but also as a result of diseases, the lens of the eye can become cloudy. This is known as a cataract. Those affected see through a pane of frosted glass. Vision can be restored through an operation that removes the clouded lens and replaces it with an artificial lens. In glaucoma, the pressure in the eyeball is so strong that the light-sensing cells are damaged. In extreme cases this can lead to blindness. To prevent this, eye pressure must be checked regularly and, if necessary, reduced with medication. 120 Contact lens… 121… or glasses as visual aid 1. Check for yourself how clearly you can see an object in different lighting conditions. Do the experiment with a second person. Follow the following experimental set-up: You are sitting on an armchair in a well-lit room. The second person now places an object on a table approx. 3 m away from you. Fixate the object and describe how clearly you can see it. Now the person darkens the room (lights off, the room should be minimally lit). After a short pause (your eyes should have got used to the darkness) fixate on the object again and now describe how well you can see it. Compare the two results and explain the cause of your observation. 2. Explain why in Task 1 your eye only gradually got used to the darkness. To clarify, have the second person look first into the dark and then into the light and describe how their pupil changes. It's your turn! a e b c d 3. Look at Figure 117. Not all rays are refracted. Which not? If you already got to know their name in physics class earlier this year, use the correct physical term. 4. Hold your book in front of you with your arms outstretched. Close the right eye and fix the black point with the left eye. Pay attention to the black star to the left of the point without moving your eye. Describe your observation and explain it. 5. Enter the terms you are looking for in the grid on the right. Umlauts are to be written as umlauts. Read wrong shows you the red gridded loading attacked the prerequisite for vision. a) Adjustment of the eye to different object widths b) innermost eye layer c) light-sensing cells that enable light-dark vision d) eye hole e) visual aids 71 ​​For testing purposes only - property of the publisher öbv

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