Some people with visual impairments experience "night blindness," whereby travel at night or in poorly lit areas is either impossible or greatly hampered, unless they use strong lighting. This is especially true of persons with retinitis pigmentosa (RP), an inherited condition that affects the rods, the specialized cells in the retina of the eye that assist in night vision. As a low vision therapist at five ophthalmology practices in Utah (low vision rehabilitation services), over the years I have helped scores of persons with RP get lighting devices for night travel or even for use in dark auditoriums, hallways, and stairways. There are many kinds of lights that people who are visually impaired can use for night travel. First, there are conventional halogen or krypton bulb flashlights. Second, there are dual "sport lights" with a combination fluorescent tube for general travel, illuminating a wide path, and a spot krypton bulb for checking a specific area or item. However, many persons with RP or other conditions that lead to night blindness often find that these first two categories of lights are just not bright enough for mobility purposes.
Among the most useful lighting devices for people with night blindness are three other categories of lights for night travel. First, there are high-power, adjustable beam flashlights that are rechargeable. Police officers often use this powerful type of bright light for work at night. Next, high-power headlamps have recently become available for night travel and other uses. They allow the traveler to be hands-free while seeing the path ahead at night. Finally, there is the extremely wide-beam Wide-Angle Mobility Light, whose features put it in a category by itself. This article discusses and recommends the best lamp in each of these three categories. (High-tech night vision aids, which amplify existing light, are also available, but they are not covered here because the products that are sophisticated enough to be useful are prohibitively expensive.)
High-Power, Rechargeable Lights
The Streamlight brand of flashlights is my choice for a high-power, adjustable-beam rechargeable light. Streamlight flashlights are available in a variety of models and with a variety of features. The PolyStinger (8.7 oz., 7.4 inches long), made of supertough nylon, is available in a polymer cover that is either solid black, yellow and black, or olive and black. The Stinger model (10 oz., 7.4 inches long) is made of machined aluminum and is black. The PolyStinger and Stinger models deliver up to 15,000 candlepower for one hour between charges. Both units have a brilliant xenon bulb and come with a spare bulb in the tail cap. Both units have a push-button switch and a snap-on charger. For their size, they are the most powerful rechargeable flashlights ever built. The PolyStinger, in a yellow-and-black nylon case, has been the favorite of people visiting our clinic because of its compact size; its bright light output; and its comfortable, easily visible, yellow-and-black case.
Streamlight also makes several even more powerful lights, which were originally designed for police work. These models have an intense light output, ranging from 25,000 to 75,000 candlepower. The new UltraStinger delivers up to 75,000 candlepower for one hour between charges. However, it weighs 1.1 pound, so is almost double the weight of the PolyStinger, and is 11.75 inches long. Other bright units by Streamlight weigh up to 2.8 pounds and are bulkier, measuring from 13 inches to 17.5 inches. I have found that for most persons with low vision, these models are too heavy and bulky to carry. Despite their higher light output, most people generally prefer the lighter, more compact, PolyStinger or Stinger models that fit into a pocket.
A number of other models by Streamlight are even smaller and more lightweight than the PolyStinger or Stinger. However, these models may not deliver enough light for most persons with low vision for use in night travel.
I prefer the Streamlight flashlights to the competing MagLite brand of flashlights because of their limited lifetime warranty, excluding the bulb, battery, and charger holder. Also, parts and repairs for the Streamlight can generally be obtained and done locally, as opposed to the MagLite. In addition, the level of brightness, polymer coating, and quality seem much better in the Streamlight units.
Many of the headlamps that are on the market are intended merely for reading in bed or for doing crafts. My brother, who has done volunteer dental work in rural areas of Peru, recently took a headlamp with him to help provide sufficient illumination while performing surgeries. A headlamp used for night travel by a person with RP or a similar visual impairment must be very bright, yet have sufficient battery life to be practical. After careful comparisons, I found the Vor Tec Headlamp, by Princeton Tec, to be the brightest unit available. It offers the highest power-to-weight ratio of any headlamp in its class.
Part of the reason for this superior brightness may be that the dimpled reflector used by Princeton Tec with its halogen bulb helps to concentrate the halogen light beam. Other headlamps use a standard flat or smooth reflector, which generally produces a more scattered or diffuse light. Also, other comparable headlamps (like the Petzl or the Streamlight) generally use only a krypton bulb. Although they have an adjustable beam, which illuminates either a broad area or focuses on a specific spot, they do not have nearly the same bright output of the Vor Tec Headlamp because of the type of reflector and bulb they use. The Vor Tec can use either a halogen or a krypton bulb with a corresponding reflector.
The Vor Tec Headlamp has an adjustable headpiece, which can tilt to almost any angle desired while walking, that helps to illuminate curbs, stairs, and drop-offs in the path of travel. Three straps secure the headlamp to your forehead and minimize the already light weight. The unit uses four AA batteries, which are included.
Sealed O-rings prevent water from getting into the bulb and batteries, and the entire unit is rated waterproof to a depth of 2,000 feet. The headlamp has a lifetime warranty, yet is extremely affordable, at only about $40.
As noted, two types of bulbs and two types of reflectors are included with the Vor Tech headlamp. The halogen bulb, when used, provides a narrow beam but with a very bright light. The krypton bulb allows a wider beam, but with a more diffuse and less-bright light. When using the krypton bulb, you also insert the standard flat reflector in place of the dimpled reflector (which concentrates the light). The bulbs and reflectors are easy to interchange. However, most users with low vision would likely prefer to use only the halogen bulb with the dimpled reflector because of its much higher intensity and focused light.
The Wide-Angle Mobility Light
The Wide-Angle Mobility Light (WAML), made by Innovations, is a heavier light, but its extremely wide beam is not available in any other unit. It comes with a shoulder strap for more convenient carrying and is rechargeable. It is so bright that a person with low vision who uses this light may feel like he or she is carrying a halogen headlight from a car. A full charge takes approximately 14 hours and lasts about 1.5 hours. The biggest drawback of this unit is its size and weight, which may be a deterrent for older persons who cannot handle the heft or younger people who do not want to stand out by using a larger light.
A competing light in this category is the LiteBox, by Streamlight, which has an extremely powerful, 70,000 candlepower lamp and can run up to 8 hours between charges (much longer than the WAML). It can be used in a spot or flood mode, on either DC rechargeable or AC. Its weight, 7.4 lbs., is comparable to that of the WAML. The WAML is slightly brighter than the LiteBox, and has a much wider beam, which is very helpful for a visually impaired person who travels at night.
Over the years, I have dispensed many WAMLs to persons with RP, who have difficulty with night travel. The WAML has been the brightest wide-angle light on the market.
Within the three main categories of lights for visually impaired persons who have difficulty with night travel, the three lamps highlighted here are my top picks. The PolyStinger or Stinger is my choice for a high-powered, rechargeable flashlight with an adjustable beam. It is lightweight and compact, yet has a bright light output. The Vor Tec Headlamp is my recommendation for a headlamp. It provides a bright light, while allowing the traveler to be "hands free" when walking. Its lamp can tilt to almost any desired angle, and it has a lifetime warranty. The WAML has an extremely wide beam and is almost equivalent to carrying around your own headlight. Its main drawback is its weight and size. The final choice among these three lights will depend on your specific needs and personal preferences.
Product: Streamlight PolyStinger or Stinger rechargeable flashlights
Manufacturer: Streamlight, 1030 West Germantown Pike, Norristown, PA 19403; phone: 800-523-7488; fax 800-220-7007; web site: <www.streamlight.com>. Price: $80 to $100 at hardware, lighting, or police supply stores.
Product: Vor Tec Headlamp
Manufacturer: Princeton Tec, P.O. Box 8057, Trenton, NJ 08650; phone: 609-298-9331; fax: 609-298-9601; web site: <www.ptsportlights.com>. Price: $40 at many sporting goods stores.
Product: Wide-Angle Mobility Light
Distributor: Maxi-Aids, 42 Executive Boulevard, P.O. Box 32009, Farmingdale, NY 11735; phone: 800-522-6294; web site: <www.maxiaids.com>. Price: $165.
The following ratings chart of accessible voting machines was printed incorrectly in the November 2002 issue of AccessWorld. The correct version appears here and in the online version of the November issue, available to subscribers at http://www.afb.org/ accessworld.asp. Because the Help America Vote Act of 2002 (H.R. 3295), which was signed into law by President Bush on October 29, 2002, makes this article so timely, the online version of this article is available to nonsubscribers as well.