Telescopes and binoculars are multi-lens devices that are used primarily for viewing the distance, but can be adapted for use at closer distances. While most of us are familiar with the common celestial telescopes and bird-watching binoculars, the systems for use by those with low vision are miniaturized. Continue reading Telescopes as Distance, Intermediate, and Near Low Vision Aids
Adapting to low vision should start with a comprehensive eye examination to optimize your vision with the best eyeglass prescription. This prescription is for distance and near viewing. What defines those with low vision is that even with the best prescription, they are unable to get perfect vision. More is needed. Continue reading Eyeglasses Used for Magnification
Hand-held magnifiers can be found almost anywhere. These magnifiers come in many styles, sizes, and magnification powers. Commonly, they are sold as either round or rectangular clear lenses, with a handle. Other types include small pocket magnifiers and a plastic ‘card’ style.
The actual amount of magnification that you get form a hand-held magnifier is variable and dependent on how you use it. Optical lenses have an optical property called focal length. If the lens is held above the page, at the focal length, you will get the magnification indicated by the manufacturer. If you hold it closer to the page, at a distance less than the focal length, you will get less magnification. Magnification is also dependent on whether you wear your distance glasses, your bifocals, or no glasses at all. Continue reading Hand-held Magnifiers
Video Magnifiers and CCTVs
Video magnifiers and CCTvs vary in size, but are basically a camera, a screen to view what the camera ‘sees’, and a light source. The size will determine its usefulness for various reading tasks. While most video magnifiers are hand-held and portable, most CCTV units requires its own space on a desktop.
Both have some of the same features:
- More than one magnifying level;
- True color mode is seeing the colors on the screen as they appear on the page;
- Inverse mode is the capability to reverse print to white on a black background; and
- Other color modes, such as yellow print on either a blue or black background, or the reverse which would be blue or black print on a yellow background.
Those are the similarities. Here are the differences: Continue reading Electronic Low Vision Aids: