Mac OS X includes several technologies to assist you if you have difficulty seeing the computer screen. They include options for magnifying the screen or specific objects on screen,  adjusting the display characteristics to make it easier to read.

Mac OS X Features

VoiceOver

The Universal Access capabilities of Mac OS X are now enhanced with a spoken interface that provides a new way, through speech, audible cues, and keyboard navigation, to access the Macintosh.

Zoom

With Zoom view you can magnify everything on screen making it larger and easier to see. Text and graphics are enlarged for easier reading and QuickTime video plays magnified without any performance degradation, a capability not available on any other operating system. The powerful Quartz rendering and compositing engine makes Zoom view possible, delivering magnification up to 40x, and sophisticated filtering and anti-aliasing to make text and graphics look good at larger sizes.

Zoom includes a number of options like the ability to set maximum and minimum values for rapid zooming in and out, a preview rectangle that outlines the portion of the screen that will be magnified, and the ability to customize how the screen moves as you navigate with the mouse pointer.

Scalable Cursor

Mac OS X enables you to easily increase the size of the mouse cursor so it's easier to find and follow when you move the mouse.  The cursor remains scaled to your preferred size even when the cursor shape changes from an arrow to an I-beam, to cross-hairs, or any other shape.  It remains in effect until you change it, even when you logout, shutdown or restart your computer.  Cursor scaling works together with other screen magnification technologies in Mac OS X, allowing you to combine them in unique ways to suit your needs.

Talking alerts and spoken items

Talking alerts and spoken items provide an audible method for getting feedback from the computer. With talking alerts visual notifications are spoken aloud by the computer providing an audible method that alerts you when the computer needs your attention. Spoken items reads back the text under which you are holding the mouse and can also read back selected text when used with a customizable key combination.

Display Adjustment

Mac OS X includes flexible display adjustments with which you can control contrast by switching the screen to White on Black or using the enhance contrast slider for varying degrees of contrast, and set Mac OS X to display in grayscale, removing all color from the screen.

Safari Cascading Stylesheets (CSS)

The Safari web browser included with Mac OS X features additional Universal Access preferences for web browsing. For example, a checkbox can be set to prevent a web page from being displayed using fonts smaller than the minimum size you set, from 9 to 24 point.  By default, pressing the Tab key in Safari navigates only the toolbar and the form elements on a page. Pressing Option-Tab will navigate every element. If you prefer, you switch this behavior so pressing Tab key by itself will navigate every element and pressing Option-Tab navigates only the toolbar and form elements.

Using the style sheet pop-up preference, you can apply a custom cascading style sheet, called a “css”, that changes the way a web site is displayed without requiring the web site author to make any changes.  This is a great way to customize the appearance of web pages to suit your specific needs.

Third Party Solutions

ARTIS Software

• Screen Loupe
  A desktop utility that displays a magnified view of whatever is underneath your mouse cursor.

Bitstream

• Tiresias Fonts Collection
  A collection of typefaces for the visually impaired.

katieplayer

• Daisy 2
  Playback for Mac OS X.

MacChampion

• PinPoint
  Provides an image around your cursor to make it more identifiable, especially on large monitors.

RJ Cooper

• Biggy
  Gives you hundreds of large, highly-visible cursors, including animated and left-handed versions.

SubRosaSoft

• Macnifier
  A free utility for magnifying part of your screen.