Types of Disabilities: Blindness Flashcards
Blindness
May refer to a total loss of vision or to partial blindness, where sight may be extremely limited (low vision).
Causes of Blindness
Some causes:
- Diabetes
- Macular Degeneration
- Glaucoma
- Accidents or traumatic injuries to the eye
- Stroke
- Retinitis Pigmentosa
Legal Definition of Blindness
Visual acuity of 20/200 with corrective lenses or a field of vision that is 20 degrees in the eye that has the best vision.
ICT Challenge: Cannot see digital or electronic interfaces (computers, ATMs, mobile devices, airport kiosks, TVs, printers, copiers, phones, GPS devices, etc.)
Solutions:
1. Screen readers can read interfaces and content out loud but only if they have been designed to be accessible. Screen readers do not announce text styles such as font, color, size, bold, and italic.
2. Self-voicing interfaces and applications can communicate to users without the need for a screen reader, but these are mostly good for broadcasting information because they usually do not interact with the interface or content like screen readers do.
3. Refreshable braille output devices use screen readers to convert digital text to braille. Typically expensive and only a minority of blind people know how to read braille.
ICT Challenge: Cannot use screen readers on digital content not designed with accessibility in mind.
Solution: Interface designers and content authors can edit the markup to make it compatible with the assistive technologies used by blind people.
ICT definition
Information and Communication Technology
Architecture and Built Environment Challenge: Cannot see when walking.
Solutions:
1. Canes help blind people feel their surroundings as they walk.
2. Service animals trained to assist blind people help them navigate their surroundings.
3. GPS-based walking instructions with an audio interface, either automated or via a remote human navigator.
4. Raised tiles on the ground to indicate the edge of a platform, a pathway along a sidewalk, the beginning of a staircase, etc.
5. Eliminate low-hanging architectural features that a blind person could bump into.
6. Clear pathways without obstructions in hallways and sidewalks.
Architecture and Built Environment Challenge: Cannot see signs or other text on buildings or other areas in the built environment.
Solutions:
1. Map and geolocation apps on mobile devices can announce the names and descriptions of buildings and other location-related information.
2. Braille labels and descriptions on entrances, rooms, bathrooms, historical markers; labels must be easy to find. Only a minority of blind people can read braille though.
3. Tactile models of the exterior of buildings, or of floorplans of the interior of buildings, help blind people form a mental map of their surroundings.
Consumer and Industrial Products Challenge: Cannot see or feel the controls on flat interfaces on consumer devices such as microwaves, ovens, dishwashers, etc.
Solutions:
1. Alternative interfaces with knobs or other tactile controls
2. Audio interfaces
3. Remote control through mobile apps
Consumer and Industrial Products Challenge: Cannot read the text on the containers or packaging for consumer items such as medicine, toothpaste, shampoo, sunscreen, hand cream, personal care products, foods, drinks, or candy.
Solution: Embossed braille (or braille stickers) on packaging and product containers help consumers identify items both in the store and after purchase.
Consumer and Industrial Products Challenge: Cannot read money to determine its value.
Solutions:
1. Apps on mobile devices can photograph the money and read the value to blind people.
2. Paper bills and coins could be manufactured in different sizes, shapes, or textures.
3. Non-cash systems of payment can allow blind people to make financial transactions via computers, mobile devices, or on-site payment hardware with screen readers or self-voicing output.
Consumer and Industrial Products Challenge: Cannot read books, magazines, posters, postal mail, or other printed materials.
Solutions:
1. Optical character recognition software can convert scanned images of text into digital text readable by screen readers.
2. Information can be placed online or in other digital formats to allow blind people to read the materials using their own assistive technologies.
ICT Challenge: In websites and other technologies, images, controls, and other meaningful elements that do not have text alternatives.
Solution: Provide text alternatives for non-text information.
ICT Challenge: Videos without text or audio alternatives, or an audio description track.
Solution: Provide audio alternatives for video content.
ICT Challenge: Websites, web browsers, and authoring tools that are not fully keyboard accessible.
Solution: Ensure that all website functionality can be performed with a keyboard and does not rely solely on the mouse.
