Types of Low Vision Filters

For sufferers of low vision caused by glaucoma, macular degeneration, cataracts, diabetes and other disorders of the eye, bright light and glare can cause discomfort, decrease visual acuity and compromise independent living. Prescription eyeglass filters in colors ranging from red to gray offer protection from harmful UV and blue light, increase contrast and reduce the discomfort caused by bright outdoor light and certain kinds of indoor light.

Filters for Contrast

• Perceiving contrast in the visual field is essential to distinguish foreground objects from the background, crucial for everyday tasks such as negotiating stairs or picking up items from a desk. Low vision sufferers may have difficulty making this distinction, especially in bright light. Prescription eyeglass filters in yellow, red, orange and amber increase contrast vision, allowing greater distinction between foreground and background.

Filters for Glare

• Colored filters reduce glare and improve contrast

  Glare from a variety of sources, such as bright sunlight, indoor fluorescent lighting, or the "veiling" glare caused by cataracts, not only compromises vision but also causes pain and discomfort. Filters in cooler colors such as plum, gray, green and blue help to block harmful blue wavelengths and UV light and reduce glare, and can be worn inside and outside for maximum comfort.

Polarizing Filters

• Polarizing filters aid in reducing glare by reflecting concentrated sunlight. Also available in combination with colored filters, polarizing lenses sharpen the visual field and reduce the discomfort associated with bright outdoor light. These filters also help to minimize the discomfort of bright indoor lighting, especially from concentrated sources.

Photochromic Filters

• Prescription filters and lenses reduce harmful UV rays

  Photochromic lenses, known best under the trademark Transitions, darken in the presence of UV rays and lighten when indoors. According to optometrist Gary Heiting, photochromic filters offer nearly complete protection against UV light. Photochromic filtering is available in gray, brown and green and red for the reduction of glare and discomfort associated with low vision conditions, and can eliminate the inconvenience of switching glasses in different lighting situations.