Ключевые слова: background, care, clinic, closeup, concave, concept, convex, correction, cylinder, defect, device, diagnosis, diagnostic, diopter, doctor, examination, eyes, farsightedness, frame, health, holder, instrument, lenses, measurement, medic, medical, medicine, nearsightedness, object, ophthalmic, ophthalmological, ophthalmologist, ophthalmology, optic, optical, optician, optometric, optometrist, optometry, patient, prisms, red, service, set, spectacles, sphere, test, trial, vision, visual,