And is artificial lighting always useful? “Mandry” asked a specialist
There is a stereotype that excellent students at school are easily recognized by their glasses. They are said to be constantly sitting behind books, which spoils their eyesight. A high visual load can indeed lead to the development of myopia, but it is only one of the risk factors for the disease. Genetic predisposition should not be discounted.
However, reading in dim light is harmful. That’s because in low light conditions, it’s hard for the eye to focus, and the eye muscles get overstretched. However, myopia will not develop overnight. It’s just that, most likely, when you close the book, you will feel discomfort in your eyes and a headache. For a while, your visual acuity may even decrease. When your eyes rest, the symptoms will go away.
If reading in low light becomes a habit, you will most likely need to make an appointment with an ophthalmologist soon. Prolonged visual strain can cause false myopia at first and then lead to overt myopia. And you should definitely not experiment if you already have glaucoma, retinitis pigmentosa, age-related macular degeneration, cataracts, complicated high myopia, or other eye pathologies.
You shouldn’t go to extremes either. Excessively bright artificial lighting damages the photoreceptors in the retina, the eye muscles become overstretched, and the body begins to defend itself. As a result, symptoms such as temporary decreased vision, fatigue, watery eyes, and redness of the eyes may appear.
A sharp “jump” in contrast causes the same symptoms. Therefore, you should not read an e-book, work on a computer, or watch TV in pitch black. In addition, the screens of electronic devices emit blue-violet light, which is dangerous to the retina. That is why it is recommended to wear glasses with special lenses that block harmful blue-violet light and transmit beneficial blue-blue light.
What is the minimum temperature a person can tolerate?
It’s easy to solve the lighting issue. There is a standard: 200 lumens per 1 m². One conventional 60-watt incandescent light bulb provides approximately 730 lumens. To have enough light in a 10 m² office, you need at least 2000 lumens, or three such bulbs. However, natural daylight is still better. In childhood, it plays a key role in the physiological development of the retina.