In 1965, a large study was conducted in the United States that examined the amount and type of lighting required for visually impaired people.
It is known that, in general, a visually impaired person needs three times the amount of light to perform an action (such as reading) that a person with normal vision needs.
A person with normal vision who wants to read will need a 50-watt bulb. A person with poor vision will need 150 watts (excluding people suffering from Retinitis Pigmentosa, albinism, achromatopsia, and photophobia).
A study that examined the ability to manage in room lighting found that a person with normal vision can manage well in standard room lighting using two 40-watt (fluorescent) lamps.
A visually impaired person will need 6 40-watt lamps (fluorescent) to be able to manage in a standard room.
So, all that's needed is to increase the lighting?
There is a thorn in her side. People with various pathologies can be sensitive to strong light from certain types of lighting, such as fluorescent.
Fluorescent lighting, which has short, blue wavelengths that focus in front of the retina (while green and yellow light waves focus directly on the retina and some red light waves focus behind it). In addition to being unhealthy for the skin and eyes, blue light contributes only slightly to visual acuity and visual perception but places a great deal of strain on the visual system in trying to focus the blue light.
There are several possibilities for improving the quality of life regarding lighting.
You should try to reduce sources of short-wavelength blue light, such as fluorescent lights, by changing the type of lighting to LED lighting. There are also special glasses that have built-in LED lighting that provides focused lighting on the reading material and prevents glare.
Another option is sunscreens that block short light waves to a desired level, causing a feeling of relaxation and comfort in the eyes on the one hand and increasing the sense of contrast on the other.
Therefore, when you want to create a more comfortable and safer work environment for people with visual impairments, you should reduce blue light and use appropriate sun filters.
