THE BEST TYPE OF LIGHT FOR LOW VISION

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The partially sighted learn very quickly that light is extremely important to the ‘seeing process’.
While many low vision patients experience photophobia or are very glare sensitive, they also require a tremendous amount of light to perform tasks with their low vision aids or reading glasses. The correct use of lighting is just as important as using the correct low vision aid. If a person is able to read outside with their back to the sun or can read by a sunny window but cannot read in their home, they most likely do not have the correct lighting.
The Best Type of Light For Low Vision
1. Why is light so important?
It is essential that the visually impaired ensure they create optimum lighting conditions wherever they are in order to maximise their vision.
Lighting is a crucial issue if you experience sight loss, at home and away. A good light source can make a dramatic difference to everyday tasks such as reading, writing, food preparation and choosing clothes. Good quality light will help you improve your independence and maintain your personal safety.
The partially sighted learn very quickly that light is extremely important to the ‘seeing process’.
How we see

• Seeing can be likened to the process of taking pictures on a film with a camera which you then get developed. The retina is like a camera film which stores an image of what we are looking at. The image directed onto the retina is then sent along to the brain where it is processed, like developing a camera film. Therefore we actually ‘see’ in our brain with the light information sent to it from our eyes. This whole process happens very quickly so that everything we see is in focus.

• Why is light important to vision?
  • Our eyes need light to work. Light entering the eye is collected by the retina and processed by the brain to obtain the pictures that we need to see. Light is an essential part of this process, for example it is difficult to read when light levels are low. Sometimes light can cause problems for our vision.

• What are the problems with light that can occur?
  • There are times when the amount of light or the quality of that light can affect our ability to see. Many people with low vision need more light than usual to read. However, too much light can cause problems from glare.

• To summarise – there are many products to help overcome partial sight loss from contact lenses to massive magnification instruments. However, experts are in agreement that the easiest and most effective aid to improving sight for all of us is simply good quality light.

2. What is the best type of light?
There are two types of artificial light:

A. Traditional artificial light
The most commonly used bulbs are filament light bulbs. These are usually balloon-shaped with wires inside. The brightness of these bulbs depends on the number of watts they have. The higher the number of watts, the brighter the bulb will be. This type of widely used light has a yellow tinge which can distort contrast and colors and produce glare. This light source is not recommended for partially sighted people.
B. Simulated daylight light
This recreated clean crisp light provides relaxing and healthy lighting conditions for your eyes. It increases contrast and clarity and reduces glare. This type of light delivers all the high quality lighting options needed by partially sighted people.

Lighting technology explained
The best way to explain in technical terms the differences in light is with the light measurement ‘Temperature Kelvin’ (°K) – which is, in a nutshell, the color of the light. The color variation is referred to as the color temperature and is measured in degrees Kelvin. The scale ranges from the color of a candle flame at around 2000°K to a deep blue sky color at around 10,000°K. The color of ‘average noon light’ (5,000°K – 6,500 °K) is white and under this white colored light white objects appear whiter and all other colors appear most natural. This is the case for every day objects and images and so helps those with low vision to see more clearly.
The following diagram shows the differences between simulated daylight and normal artificial light:

Advantages of simulated daylight bulbs and tubes:
1. Increases contrast
2. Increases clarity
3. Reduces glare
4. Most environmentally friendly (low energy)
5. Safest light for partially sighted people (low heat)
6. Most comfortable light for your eyes

Not all standard lamps are the best option for low vision lighting requirements.
3. Using adjustable task lamps

• According to the Royal National Institute for the Blind (RNIB) as well as having good general lighting in the room, it is important to have a second light source, for example a task light that can shine directly onto what you need to see.
• If you are near a window you can sit down so that you have your back to the window. This will mean that the light comes over your shoulder and shines on what you want to see. However, there are problems in using external light as it is inconsistent, can be glary and the direction can’t be changed. It is often easier to use a lamp that shines light onto the activity, often referred to as task lighting.
• Adjustable lamps are particularly useful because you can point them to make the light fall directly onto what you want to see. Adjustable task lamps can be floor or desk standing. They have a base or bracket to which an adjustable arm and a flexible head are attached. The best position for an adjustable lamp is between you and what you want to look at, directed at the task, below eye level.
• Not all standard lamps are the best option for low vision lighting requirements.
• In fact, only very few companies design and manufacture lamps specifically for the low vision sector. One such company is The Daylight Company which works in close cooperation with the Royal National Institute for the Blind (RNIB) in the UK and has done so for a number of years. The RNIB provides valuable advice to the company’s in-house design team on the research and development of innovative new lamps and accessories for the low vision sector.

All Daylight™ lamps are fitted with natural Daylight™ bulbs or tubes. Therefore every single person who uses a Daylight™ lamp benefits from the unique features of this innovative form of light – all of which are particularly important to people who are experiencing sight loss or are visually impaired.
Daylight™ lamps have been designed to combine form with function. These innovative lamps are practical and life enhancing pieces of equipment while at the same time their stylish design will grace any home or work place.


http://www.lowvision.com/products/lighting