Low vision non-optical devices can include adaptations such as reading stands, supplemental lighting, absorptive sunglasses, typoscopes, and locator dots. They are often recommended as part of a low vision examination, and can be used in combination with magnifiers and other low vision optical devices that can help with reading and a variety of tasks.
Some of the most helpful low vision non-optical devices include:
Flexible-Arm Task Lamps
Proper lighting is critical for good vision. As we age, a person age 65 or older probably needs 15 times as much light to read as a 10 year-old. And importantly, a person with low vision may need 3 times as much light to read as a person their age who does not have a vision loss. Flexible-arm desk or floor task lamps are perhaps the most helpful and important non-optical devices for many people.
Some advantages of flexible-arm task lamps are:
- They are easily obtained at a variety of stores, catalogs, or online
- They are generally relatively inexpensive
- Can be adjusted to a variety of settings and tasks
However, some lamps may become hot, so be careful not to touch them. Also, be careful to position the light so that it is not coming right into your eye, and creating glare.
There are many types of lamps—incandescent, halogen, fluorescent, LED, and full spectrum. Try different lamps to see what you prefer. Try to choose one that is a low “Kelvin” rating—under 5,000 Kelvin (K), so that it does not emit ultraviolet or blue light. Perhaps even more important than the type of light is the position of the light—particularly the distance from the lamp to the task you are doing or to your eye. Bring the lamp closer to help maximize the light delivered to the task and your eye.
Reading Stands
Reading stands help facilitate success in both reading and writing. They not only provide beneficial positioning of reading and writing materials, they also:
- Bring reading and writing materials closer to your eye, thus helping to achieve “relative distance” magnification—enlarging things by bringing it closer
- Help you see a wider field of view—more lines and text at a time, because the image is closer to your eye
- Allow better illumination, because you are not as bent over, which blocks out the light
- Provides better posture and ergonomics, which leads to less fatigue and strain on your neck and back
Make sure you use a reading stand when you read or write with your stand magnifier or other optical devices. It will increase your success dramatically.
Absorptive Sunglasses
Glare is a major problem and concern for many persons with low vision. Absorptive sunglasses help filter out bothersome glare and harmful light rays. Most sunglasses now block out ultraviolet light. However, to block out “blue” light, which we are concerned about for macular degeneration and other eye conditions, sunglasses need to have some amount of yellow in them. The colors of sunglasses that contain some yellow and block out “blue” light are: amber, orange, amber/orange combination, plum, and yellow. Grey and green-grey colored sunglasses do not block out any blue light. Grey and green-grey sunglasses interestingly also do not provide as good contrast as amber, orange, plum, and yellow.
Some advantages of absorptive sunglasses are:
- They reduce bothersome glare
- They block out harmful rays of light. Most block out ultraviolet (UV) light, and amber, orange, plum, and yellow colored sunglasses also block out “blue” light
- Amber, orange, plum, and yellow colored sunglasses also help enhance or increase contrast
- Yellow colored sunglasses are fabulous for use indoors when reading, writing, doing hand work, or using a computer, to reduce glare and enhance contrast
- They are generally quite inexpensive and are easily obtained
- They can be fitted over regular glasses, or they are available in a clip-on or insert
Colored Acetate Sheets
When placed on the page, a translucent acetate sheet—especially yellow—can enhance the contrast between the print and background, making words and letters appear darker and easier to read. They are readily available at office supply stores, and are an alternative
Typoscopes
A typoscope looks like a signature guide, but it is not. It is a very inexpensive but helpful black plastic device with a cutout, to assist you when reading. It is a marvelous tool to help a person with low vision keep their place on the line, to track along the line as you read, and to track back to the beginning of the next line. It also helps draw attention of where to look on the page, and provides excellent contrast while reading. A person with a stroke and resultant hemianopia is especially benefitted by a typoscope and these strong features when reading.
Locator or Bump Dots
Locator or “Bump” dots can be used to mark appliances, dials, and other items for a person with low vision. They are not only highly visible, but also have raised dots of various sizes or shapes (usually round or square), which can help locate a certain place on a dial, control, or device. They can be used on ovens and stoves, washer and dryer dials, a thermostat, microwave, phone, calculator, and countless other applications.
Using Optical and Non-Optical Low Vision Devices
Before any low vision device or non-optical aid can be effective and comfortable, you will need to:
- Be motivated to use the device for specific tasks
- Be confident that the device has been appropriately prescribed
- Know how to maximize the use of the device
- Know its potential and limitations
- Supplement your use of optical devices and all tasks with appropriate lighting. To achieve the best results from the use of any low vision optical device, lighting from a flexible-arm task lamp can often prove to be essential
- Use a reading stand to position and hold the reading and writing materials
It’s also important to realize that it often takes time, patience, practice, and much encouragement and support to learn how to use low vision optical devices successfully. Family and friends can play an important role in encouraging you to be patient and to keep trying. They can also help you experiment with various lighting, including different types and positioning, and to use the devices correctly, as you were trained to do with the low vision specialist.