The Dr. Bill Takeshita Foundation

Last Modified: Fri, 17 Aug 2007

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Light is the most fundamental element of vision. It provides contrast between the object and the background, enabling the eyes to send signals to the brain to be perceived. When there is not sufficient light, there is no contrast between the object and the background. For example, in total darkness, everything appears black and there is no contrast. Conversely, when there is too much light, such as looking at stars in the sky during a bright sunny day, the stars cannot be seen because there is insufficient contrast. Patients with low vision can improve their functional vision by modifying the lighting levels to help them in their daily lives. For example, the use of desk lamps can increase the contrast level to make reading print written in pencil easier. Similarly, the use of sunglasses can reduce the lighting levels to improve the contrast that allows patients to see concrete steps and curbs.

Sensitivity to glare and bright light are common complaints of patients with low vision. Their eyes are not able to adapt to high levels of illumination and they are often “blinded by the light.” Many patients with low vision have difficulty using over the counter sunglasses because they are often too dark or not dark enough. Low vision specialists can customize filters to maximize contrast and not reduce vision. Specialized filters such as multiple pinhole glasses, Corning CPF, Melanin, and NoIR lenses are designed to reduce glare and improve eye comfort without reducing vision. These specialized sunglasses are not available “over the counter,” but may be the most effective optical treatment to improve visual function when outdoors. They also protect the eyes from the harmful rays of the sun.

Interior lighting conditions can be customized to improve visual function of children and adults at home, work, and at school. Paint and wall coverings are one of the most effective treatments to alter the ambient lighting of a room. The use of dark colors will reduce the overall ambient lighting while lighter colors will brighten the room. Ceilings painted with an off white paint will increase the brightness of the room and will increase the perceived size of the room, especially when table and floor lamps shine light towards the ceiling. Light colored paints should be used on walls and ceilings for patients who require higher illumination. Base moldings, door jams, and crown moldings made of dark woods such as mahogany will provide contrasting visual clues to help patients with low vision to navigate more easily and accent the features of the room. Conversely, patients who are bothered by light will benefit from using darker paints, floors, and window coverings to reduce the room illumination.

Lamps and lights can significantly improve visual unction of patient with low vision. The first step is to obtain the appropriate ambient illumination. This is the amount of light that fills the room and illuminates the ceilings, walls, floors, and furniture. It is important to note that ambient lighting is not designed to provide lighting for reading, cooking, or performing specific tasks. Patients who are bothered by glare and bright light will benefit from using 45-watt incandescent bulbs placed in table and floor lamps with opaque fixtures to provide diffuse light on the walls, floors, and ceilings. The opaque shades will eliminate glare and the incandescent light bulbs will provide minimal light. Conversely, patients who require high levels of illumination will benefit from using table and floor lamps with translucent shades that will allow light to pass through the shades and reflect off the light colored walls, ceilings, and floors. Fluorescent 15-watt spiral bulbs will provide high levels of light in a cost-effective manner, allowing patients to use more lamps as necessary. Do not use 300-watt halogen floor lamps because they use too much energy, generate too much heat, and can cause fires if they tip over.

One of the best methods to modify ambient lighting for patients with low vision is the use of recessed lighting. Recessed lights are cylindrical cans that are inserted into the ceilings. They are generally installed by electricians and can be placed strategically to illuminate hallways, kitchens, bedrooms and study rooms. Recessed lights can use incandescent flood or spot bulbs to provide ambient or task lightings. They are dimmable and provide high levels of flexibility for patients. The use of 85-watt incandescent flood bulbs in an R-40 can provide excellent ambient illumination while the use of halogen spot bulbs will illuminate specific work areas such as desks, stoves, and eating areas without causing glare. Recessed lights are available in a large variety of sizes and styles. Fluorescent ceiling light fixtures provide very high levels of illumination in kitchens, dinettes, bathrooms, and bedrooms at a very affordable price. Four-foot fluorescent light fixtures can hold 4 four-foot tubes and cost approximately $100.00. They also provide the highest amount of lighting at the most affordable cost. Fluorescent light bulbs do not generate much heat, they use very little energy, and they provide high levels of light. However, fluorescent light bulbs may distort the appearance of colors, they sometimes flicker, and they also produce glare for some patients. Purchasing full spectrum light bulbs, which generate light that is most similar to the sun, can eliminate many of these complaints. While the use of plastic coverings will reduce glare, the mixture of various types of fluorescent tubes can provide different colors of ambient illumination.

Many patients with low vision attempt to increase the lighting in their homes or work areas by replacing their table lamps with more powerful light bulbs. In most cases, this does not help significantly because most of the light shines on the ceilings and walls or is absorbed by the lampshade. The use of desk and floor lamps that direct light specifically on the work areas are the best solutions to help patients to read, write, play cards, see their food, and perform their hobbies. Desk lamps generally consist of a silvered or white reflective surface that directs all of the light on the reading material. Because light is directed in a precise manner, all of the light illuminates the reading material and stray light does not cause glare. Desk and floor lamps are available in various styles and they use a variety of light bulbs. Halogen light bulbs are very bright but they tend to generate a lot of heat. Incandescent light bulbs generate a moderate amount of heat but the light often has a reddish or yellow hue that is bothersome to some people. Fluorescent bulbs do not generate much heat but some will cast a bluish color on the paper and some patients do not like to read under such lighting. Thus, it is important to actually compare the visual comfort with each type of light bulb before purchasing a desk lamp. Many patients with low vision prefer the OTT full spectrum fluorescent desk lamp or a desk lamp that uses a 60-watt incandescent General Electric Reveal bulb.

Track lighting provides excellent task lighting for patients with low vision who require very high levels of illumination for reading, writing, cooking, and eating. It is an affordable alternative to recessed lighting. Track lighting consists of a rail or track that is mounted to the ceiling and small light fixtures are attached to the track. The lights can be directed in any direction and are very effective at illuminating desks, dining areas, and other work areas. Track lights use both incandescent and low voltage halogen bulbs. The beam emitted from the bulbs tends to be narrower than the beam from recessed lights. However, because they use less energy, more fixtures can be used to illuminate areas where patients need more light.

When choosing light fixtures, it is very important to learn about the type of bulb that the fixtures use. Halogen and incandescent spot lights are excellent for spot lighting while fluorescent, incandescent flood lamps, and conventional incandescent light bulbs are best for ambient illumination. The wattage of the bulbs only tells how much energy the bulbs use while the lumens describe how much light the bulbs emit. Fluorescent bulbs are the most efficient bulbs and produce the most light for ambient purposes but they tend to create glare and distort colors. Halogen bulbs are available in a variety of styles and they produce a very white light but they also emit a lot of heat and use more energy. Thus, they are best when used in recessed and track lighting.