Ключевые слова: acuity, adult, age, aging, blur, blurred, concept, defocused, disorder, disorders, eye, eyesight, focus, focused, glasses, illness, medical, medicine, message, old, ophthalmology, page, paper, presbyopia, presbyopia word, problem, reading, senior, single word, text, tired eyesight, title, typewriter, unfocused, vintage, visual, word, write, writing,