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Chapter 4: Teaching People Who are Blind or Low Vision

Reading Information—the linear aspect

Teaching Blind People

Teaching Low Vision People

Reading Information—the linear aspect

When sighted computer users view the screen, they immediately see everything that is currently displayed. For instance, they may see several windows open and position themselves side by side; the time, usually displayed on the bottom right corner of the screen, may appear; the green START button may appear in the lower left corner of the screen. When low vision or blind people look at the same screen, and they use any type of assistive device, i.e. screen readers, magnification software, or Braille displays, they can see the same information, but in smaller portions. They cannot get the view of the full screen; rather, they need to focus on its separate parts. In other words, no matter how many pieces of information are visible on the screen for sighted users, blind people will not read or view all of these pieces simultaneously, even with assistive technology. If there is a window on the left and another window on the right side of the screen, assistive technology will focus first on one window, then on the other. All the information from the screen, regardless of its position, is read in a linear form. Having the opportunity to view the whole screen versus having to read or view it linearly is one of the major differences between the way sighted people and people who have to rely on assistive technology receive the information on the screen.

When people browse the Internet with a screen reader, for instance, they will not be able to see the screen in the same way sighted people will. Sighted people are able to see the following elements at once: blue title bar on the top of the screen, with the name of their Internet browser; a menu bar, which contains items such as “file,” “edit,” “view,” “favorites,” etc; toolbars with pictures of various options; a browser window where web sites are displayed; a status bar, which often says “ready” or “done” or shows a picture of how much of a page still has to be downloaded; and a bar at the bottom of the screen, which is there most of the time no matter which program is opened. This bar usually has the START button, small icons that represent volume and other options and, finally, the time on the right side of the screen. The view may slightly vary, depending on user preferences. What is important in this example is how many elements sighted computer users see as soon as they open a program, in this case, Internet Explorer.

It is important to keep in mind that screen reader users can get access to the same information. They can read the title bar, go to the different menu options, read the content of web pages, see the status bar, etc. They can tell their screen reader to focus these elements and read them, one at a time.

Braille display users have to read in the same manner. They can see only a single line of text on the screen. There have been attempts to design a Braille display with multiple lines, i.e. to have as many lines as a standard page seen on the computer screen. It is true that this would give Braille display users a chance to quickly browse through the contents of the screen, but they still have to use their ten fingers to read the information, and thus they will not be able to do it in the same amount of time that it would take sighted users.

The aspect of linear reading is also present in assistive technology designed for low vision people. CCTVs and the magnification software deal with the same issue, although to a different degree, depending on the level of magnification. The more magnification is used, the smaller portion of the screen can be viewed. For instance, while those who use Internet Explorer with magnification 2x will be able to see the whole name of the browser they are using, all the menu items on the menu bar, most of the tools on the toolbars, and a part of the Internet Explorer window, users with magnification 6x will see only a part of the name of the browser, only several menu options, and a few tools on the toolbar.

As was the case with screen readers and Braille displays, the magnification software or the CCTV users are able to view the whole screen, but only in parts. They can tell their magnification software to focus on a given element or they can move around the screen with a mouse. CCTV users have to move the text they are reading to the right, left, up or down.

Teaching Blind People

Below I will describe concepts related specifically to teaching computers to blind people, I will discuss concepts related to teaching people who are low vision. Even though I am referring to screen reader users as “blind people” in the first two sections, and magnification software users as “people who are low vision,” I do not want to imply that these are the only possibilities. There are low vision people who like to use a screen reader instead of a magnification program or a screen reader in conjunction with the magnification program. Since I am discussing the concepts, and not all possible ways of using assistive technology, I have decided to use these terms depending on for whom the software was originally designed: blind or low vision computer users.

The Importance of Using Shortcut Keys

While it is not possible to read the information on the screen all at once, it is still possible to view it. Imagine how much time it would take for a blind user to learn what the time was, if he had to start reading the screen from the top left corner and had to go through the contents of the entire screen to get to the far right corner of the screen. It is technically possible, but I do not know a single blind user who would take the time to do it that way. What could be used instead is a shortcut key that brings the user directly to the clock.

Just to clarify, a shortcut key is a key or a combination of several keys that, when pressed, execute a certain function, i.e. focus on a certain location of the screen, like the title bar, the menu bar, etc, or perform a task: copy, paste, open a file. They are designed, as their name suggests, to provide a short way of executing a function. To narrow down the definition of shortcuts, it is necessary to distinguish between the categories: Windows shortcuts and screen reader-specific shortcuts.

Windows shortcut keys have been designed by Microsoft developers. They are shortcuts that allow sighted or blind users to perform the same action by using the keyboard as they would a mouse. It is possible, for instance, to press the Windows key, and that will bring up the START menu. Since the Windows shortcut keys can be used by both sighted and non-sighted users, they can be used without any assistive technology running. A list of such shortcut keys can be found in Windows Help.

Screen reader-specific shortcut keys can be used only when a screen reader is in operation. They are also specifically designed to accommodate the needs of blind users. A shortcut to find out what the time is, for instance, is one designed by developers of screen readers, rather than Windows developers. Sighted people can see the time without using any shortcuts, so it is not necessary to provide this option to them.

Presentation of Visual Concepts

Since blind people cannot see the screen, it is recommended that they are shown various computer-related concepts on diagrams or in any other form that will help them imagine what is occurring on the screen. I will describe how a computer concept can be presented to blind people and point out how closely it should resemble the image that sighted people see by using the example of several windows open on the screen. The idea, however, is applicable to any visual content of any given program.

The concept of having several windows open on the screen may be portrayed as several pieces of paper on top of or beside one another, where each sheet of paper would represent a different window. Sighted people notice immediately if there are several windows open on the screen; blind people will not see that right away, since their screen reader is focused on one element of the screen at a time. Only if they press a key combination (a Windows shortcut) will they know whether one or more windows are open.

It is not necessary to try to describe exactly how the screen looks, because sometimes it may not make a difference for the screen readers. In our windows example, for instance, it is not necessary to explain whether the windows are of an equal size, because the screen reader will treat them with equal respect. What is important to explain is that there can be several windows open on the screen and that there is a way, a shortcut key, to switch between them.

Teaching Low Vision People

Mouse & Color Enhancements

Since magnification software is designed for people who have enough vision to see what is on the screen, the programs come with easily customizable mouse and color enhancements, which may help low vision people to view the screen. Mouse enhancements allow low vision users to change the color and size of the mouse pointer, so that it can be easily found on the screen. Various color enhancements allow users to choose colors with which it is easier for them to view the screen. They may, for instance, find that the contrast is better when they choose black background and white or pastel colors.

Viewing the Screen

Naturally, when a higher magnification is used, a smaller area of the screen can be viewed. There are various viewing options from which low vision people may choose. This does not mean that they cannot view the magnified screen in pieces, i.e. by scrolling the mouse up, down, to the left and to the right; it simply means that there are more efficient ways of getting an idea what is happening on the screen.

Many magnification software programs come with several viewing options. The most common are: full screen (a default view, where the whole screen is magnified, and therefore only its small part is visible without scrolling), split screen (where the screen is divided into two parts: one magnified and one unmagnified), a lens (which looks exactly like a magnifying glass. It magnifies whatever it focuses on), and overlay (only a part of the screen is magnified, while the rest of the screen is not).

Chapter 1: Introduction to Assistive Technology

Chapter 2: Various Assistive Technologies

Chapter 3: Basic Principles and Ergonomics

Chapter 5: How do Blind/Vision Impaired Users Benefit from the internet

Chapter 6: Accessible Web Design

Chapter 7: Overbrook Resources

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