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Date: 9-11-2020
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Nearsightedness and Farsightedness
Not all of us have the so called normal eyes described by Figure (1). There is increasing evidence that those who do a lot of close work as children end up with a condition called nearsightedness or myopia where the eye is elongated and light from infinity focuses inside the eye as shown in Figure (2a). This can be corrected by placing a diverging lens in front of the eye to move the focus back to the retina as shown in Figure (2b).
The opposite problem, farsightedness, where light focuses behind the retina as shown in Figure (3a) is corrected by a converging lens as shown in Figure (3b).
Figure 1: Parallel light rays from a distant object are focuses on the retina when the ciliary muscles are in the resting position.
Figure 2: Nearsightedness can be corrected by a convex lens..
Figure 3: Farsightedness can be corrected by a convex lens
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حمية العقل.. نظام صحي لإطالة شباب دماغك
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إيرباص تكشف عن نموذج تجريبي من نصف طائرة ونصف هليكوبتر
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شعبة مدارس الكفيل النسوية تطلق فعّاليات مخيم (بنات العقيدة) العشرين
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قسم التربية والتعليم يعقد اجتماعاً تحضيرياً لملاكاته استعداداً لانطلاق برنامجه التأهيلي
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متحف الكفيل يعقد أولى اجتماعاته التحضيرية لمؤتمره الدوليّ الخامس
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وفد قسم الشؤون الفكرية وسفير العراق في فرنسا يبحثان سبل تعزيز التعاون المشترك
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