Importance of Light
• Ceiling lights
• Task lights
• Glare
• Daylight 
• U.V. light

A 50 year old with normal vision is said to require about twice as much light as a child for reading, rising to about ten times for someone in their 80s or older.

Conditions that affect the retina and opacities in the cornea or lens of the eye will create changes in the amount of light required for efficient and comfortable vision, and the amount of glare produced.

Poor lighting in hallways, on stairs or pathways, can significantly increase the risk of falls in older people, and increase risk of burns and cuts in kitchens and workshops, as well as making reading and other tasks requiring detailed vision difficult.

Ceiling lights

Lights attached to ceilings or walls are good for general lighting, moving around and conversation, watching TV or computer, and security.

These lights are not sufficient for task lighting, as by the time the light reaches the eye it is so diluted and weak that it is barely sufficient for good vision.

Ceiling lights may be incandescent, fluorescent or halogen. Energy efficient CFL (Coiled Fluorescent Lamp) bulbs are generally best
suited to light living spaces where lights are left on for long periods of time, as they may take a long time to warm up to their full brightness and frequently turning on and off may shorten the life of the bulb. These bulbs throw light sideways rather than downwards like an incandescent bulb with a filament, and are often heavier than incandescent bulbs, therefore they should be used in fittings made for such bulbs and are not always suitable to substitute into fittings made to take the older style incandescent bulbs. Manufacturers are working on these issues.

Portable desk light, mains or
battery powered, cool white light.
.

Task lighting

Task lighting is required for any detailed tasks such as reading, writing, sewing, workshop, crafts, applying makeup and shaving.

The best task lights are on a flexible arm to allow positioning close to and at the correct angle to light the task, without reflecting glare from background surfaces directly into the eyes. The light should be angled to minimize shadows falling on the task, which also reduces effectiveness of light.

Placing the light closer to the task increases the intensity of light. This is particularly necessary in conditions affecting the macula or central, light sensitive part of the retina such as Macular Degeneration.

• Incandescent – yellow to pink colour, may throw shadows or patchy light. Bulbs are easy to change, but may get uncomfortably hot.
• Fluorescent – energy efficient, does not heat up and comes in a range of colours from cool white, “daylight” and shades of pink/yellow. “Daylight” is best for colour matching.
• Halogen - strong pure light but gets hot quickly. Fittings may get hot to touch. Bulbs may be expensive and difficult to replace
• LED – economical long-lasting bulbs. Cool white light, often used in torches or illuminated magnifiers .

Portable lights such as torches are particularly useful for a person with low vision, as they allow control of local lighting in public areas such as restaurants, shops and public transport. They are also useful for dark cupboards and recessed plugs or key holes.

 

Discomfort Glare  +  Disability Glare

Discomfort glare occurs when too much light enters the eye creating hot, dry or excessive tearing, tired eyes, or headaches from squinting.

The use of tinted lenses or sunglasses will usually alleviate discomfort glare. The darkness of the lens is a personal choice depending on the individual’s degree of sensitivity, environmental factors such as reflected light from water, sand or concrete, eye conditions and focusing, and pupil size.

The pupil of the eye is the hole in the iris which controls entry of light into the eye. It also assists with focusing. A small pupil helps with focusing more than a large pupil, so for some people a dark sunglass lens which allows little light through creates a larger pupil and makes it harder to see.

Disability glare occurs when light entering the eye is scattered either by reflection or by opacities in the pathway of light through the eye such as from cataracts or corneal scars. This type of glare causes vision to be poorer than normal.

Conditions which affect peripheral retina such as glaucoma, retinitis pigmentosa or pigment deficiencies cause problems with disability glare, night vision and/or reduced ability to adjust to changing levels or direction of light. The balance between sufficient light to see well and reducing glare is very delicate and individual, but becomes more important with age and eye health.

Tinted lenses come in different colours as well as different levels of darkness:
• GREY – most common sunglass. Best for maintaining natural colours. Soothing for some people, too dull for others.
• BROWN – maintains brighter appearance.
• AMBER/YELLOW – cuts out haze and increases contrast. Used to enhance vision without reducing light such as in cloudy conditions, night driving and for people with opacities such as cataract and some retinal conditions. May also be used for some head injuries.
• PINK or LIGHT BROWN – often used for softening glare indoors such as from computers or overhead fluorescent lighting.
• LIGHT BLUE – sometimes used as above, or to reduce glare from page and shimmering for some reading disabilities.

DAYLIGHT

Many people prefer to read by daylight. In our climate daylight varies not only with seasonal change but almost minute by minute even if reading is done outside in an area free of shadows.

A reading light should be used indoors even during the day to give better vision, particularly for a person with low vision.


ULTRA-VIOLET (UV)

Daylight contains UV light. The light reflected from low clouds, water or concrete buildings can be particularly high in UV content.
Just as UV light causes premature aging of the skin, it also ages the structures of the eyes such as the lens (cataracts) and can damage the sensitive retinal cells.

Spectacle lenses made from plastic materials will absorb much more UV than glass lenses even if not tinted. Unfortunately the smaller spectacle frames do not protect the eyes from UV light entering around the lens, therefore additional cover from a hat or larger sunglasses will improve protection

 

Adjustable reading lamp, cool white light, floor standing.

Combination lamp & magnifier on separate adjustable arms, base on wheels.

Slimline table lamp on clamp or base. Produces white shadow free light

Lamps above are Available from Sight Loss Services, send your request to This email address is being protected from spambots. You need JavaScript enabled to view it. for more information.