Ключевые слова: 30s, caucasian, checking, checkup, clinic, diopter, discover, doctor, examination room, examine, examining, expertise, eye care, eyesight, frame, holding, indoors, job, laboratory coat, lens, male, man, measurement, medical, messbrille, mid adult, oculist, ophthalmologist, ophthalmology, optician, optometric, optometrist, profession, research, showing, specialist, test, testing, trial frame, vision,