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What is Blindness is defined at: and explain in detail?
(3/60): Ref: (349-Park 20th)WHO defined blindness: - "Inability to count fingers in day light at distance of 3 meters" to indicate less than 3/60 or its equivalent.Categories of visual impairmentCategories of visual impairmentVisual acuity Maximum less thanMinimum equal to or better thanLow vision1 6/186/60 2 6/603/60Blindness3 3/60 (finger counting at 3 meters)4 1/60 (finger counting at 1 meter)5 No light perception1/60 (finger counting at 1 meter)Light perception* Cataract: is the most common cause of the blindness in India* Refractive error: is the most common cause of ocular morbidity in India* Vision 2020: The right to sight, a global initiative to eliminate avoidable blindness was launched by WHO on 18 Feb. 1999.* Target diseases are cataract, refractive errors, childhood blindness, corneal blindness, glaucoma, diabetic retinopathy.* Four tier structure include(I) Centers of excellence 20 -Tertiary(II) Tertiary centers 200 - Tertiary(III) Service centers 2000 - Secondary(IV) Vision centers 20000 - Primary