Low Vision FAQ
Case Study | FAQ | Resources
Q. TERMINOLOGY: What are the differences between "low vision," "visual impairment," and "blindness?"
A. Standard vision is measured as 20/20. A person is considered "visually impaired" if she can see no better than 20/70 with correction in her better eye. This means she can see at 20 feet what people with standard vision see at 70 feet. If an individual's vision is no better than 20/200, she is considered legally blind. A person is also considered "legally blind" if his central vision is no greater than 12 degrees (i.e., he has limited peripheral vision and appears to be seeing things as if looking through a tube or straw). A person is typically referred to as "totally blind" or "black blind" if he has no visible sight. "Low vision" or "limited vision" usually refers to someone who has a visual impairment but is not totally blind.
Q. TEXT ENLARGEMENT: How much do I need to enlarge handouts or reading material for someone with low vision?
A. Print size will depend upon the needs of the individual. However, large print is usually defined as 16 to 18 point bold type depending on the typeface used. A standard Roman typeface, using upper and lower cases, is more readable than italicized, oblique, or condensed fonts. To enlarge print from standard 12 point original text to 16-18 point, use a 150-165% enlargement setting on a photocopier. For documents in electronic form, it is best to enlarge the font size before printing. The student is the best source of information regarding preferred print size.
Q. TEXT: Other than enlarging the size, how should I adapt text or handouts to accommodate students with low vision?
A. There are several ways:
- Use a Roman type standard serif or sans-serif font, size 16- or 18-point. These fonts tend to have more space between letters (i.e., non-condensed).
- Print text using the highest contrast possible. Light or white letters printed on a dark background are more readable than dark letters on a white background. High contrast can be difficult to achieve with colored type on a colored background. It is important to check with the student to see what type of contrast he prefers.
- Allow extra line space between the lines of text. The spacing should be at least 25-30% of the point size. For example, when using a 16-point font, there should be at least four spaces between the lines of text.
- Extra-wide margins and the ability to open a printed document flat are helpful if the document is bound.
- Use paper with matte finish, which is easier to read than a glossy finish.
Remember, the student is the best source of information about preferred text characteristics.
Q. LITERATURE SEARCHES: How does a student with low vision conduct a literature search and access the literature in preparation for a writing assignment?
A. Many students with low vision are able to access library catalogs and other databases on the Internet to search for relevant articles and books as long as computers are equipped to enlarge text on the screen and/or read the screen with speech output software. Students may also work with library staff or the disability services office to request a library assistant.
Q. LIBRARY MATERIALS: What are strategies that can be used by students with low vision to access library materials?
A. There are several alternative methods that someone who has low vision can use when reading a printed article. Pages can be enlarged with a photocopier for a student able to read large print. The article can be scanned and accessed by a computer with speech and/or large-print output. A closed circuit television (CCTV) can enlarge the printed material for the student. A reader may read the article aloud to the student. The disabled student services office may be asked to prepare printed articles in an alternative format or provide a reader.
Q. COMPUTER ACCESS: How do people with visual impairments use computers?
A. For an overview of how individuals with visual impairments can use computers, consult the publication and video entitled Working Together: Computers and People with Sensory Impairments.
For answers to more questions, search the Knowledge Base.