Narrator: Screen magnification software allows the user to enlarge the image of text and graphics being displayed on their computer screens. It does this by intercepting the video signal gong to the monitor, then magnifying and enhancing it, before sending it on to the display. Both Macintosh and Windows-based computers offer a basic magnification feature with their operating systems.

While some users find these adequate, most people with low vision, like the user shown here, experience frustration with the limitations of these programs.

Some programs are available as Freeware, but they also have limited features and a restricted range of magnification. Shareware programs can be downloaded from the Internet for as little as $50, but they also offer only minimal features. Users who find low-cost and free programs inadequate need the more sophisticated features offered by commercial programs.

This user is working with a commercial magnification program. By pressing a keyboard command, he has increased the size of the image on the screen to 16 times its normal size. In using this type of software, most users settle on a magnification level between twice as large and five times as large. More advanced users quickly learn to adjust the magnification level to suit the type of information they’re viewing and the amount of detail they want to see. In this example, the user increases magnification to view a graphical image on a web page, and then decreases it to continue reading text on the same page.

Although users can move the magnifier to enlarge a different part of the image, they can still be confused about the location of that part in relation to the image as a whole. To help users maintain their orientation, screen magnification programs provide a feature that enables them to locate their position on the original, unmagnified screen. When the user executes this command, the screen displays an inverse or a shadowed rectangle as shown here. This shadowed rectangle appears on an unmagnified view of the display, and shows which area of the screen is viewable in the enlarged mode. This feature allows users to determine which area of the image they are viewing, such as the middle, upper left or lower right section of the original, unmagnified screen.

This software also enables viewers, to issue specific viewing commands. The user shown here has chosen a viewing or window mode that determines what portion of the unmagnified image will be displayed on the magnified screen. In this mode, only a small portion of the screen is magnified, which simulates the effect of viewing the screen with a hand-held magnifier. As users move the magnifier around, using keyboard commands or the mouse, the information under the lens is enlarged. Users such as the one shown here can then adjust the lens to zoom in or enlarge specific information, such as street names. While it’s useful for graphical information, the lens mode is less efficient for viewing a web page or reading a word processing document. As shown here, the user is only able to view a small amount of text before having to move the lens. This can lead to inefficient and labored reading.

In those cases, the line viewing mode offers a better option. As the user changes to this viewing mode, only the line containing the cursor is magnified. Many users with low vision can see the unmagnified display well enough to maintain their orientation to the screen, and they use the magnified portion just to access specific information.

Some users with low vision find it difficult to read black text on a bright white background. Commercial magnification programs allow this type of user to choose from different combinations of text and background color. The most efficient way of interacting with screen magnification programs is through keyboard commands. This user prefers to use the mouse, but he’s having difficulty seeing the icon that represents the pointer or cursor on the screen.

For that reason, manufacturers have included the enhancement features shown in this scene. This feature allow users to select the size and color, and other visual aspects of the mouse pointer and the cursor which makes them easier to locate.

Commercial screen magnification programs have an added feature that can greatly assist users with low vision, like the one shown here, when reading lengthy passages on screen.

Manufacturers have either included synthesized speech output features, or made their programs integrate seamlessly with screen reading programs. These features allow users to hear text spoken through synthesized speech generated by the computer’s sound card.

Sample of synthesized speech: “…cade communications, BRCD, up 0 dollars and 37 cents to four dollars and 41 cents…”

This feature also allows users to see the text highlighted, while simultaneously hearing it spoken. Users find this feature extremely helpful when reading large word processing documents, or lengthy passages from the Internet.

Whichever type of program is chosen, screen magnification software enables users with low vision to access a tremendous amount of electronic information that was previously not available to them.