How does screen magnification software work?

The term “Low Vision” refers to a wide range of vision issues. Not just clarity and range of vision, but can also refer to difficulty with things like brightness and contrast, colour perception, scanning for information, relative size and smoothness of text, and more. “Screen Magnification”, and its related features are used to provide a range of solutions to help these individuals access information. With the increasing aging population in today’s society, age-related low vision is also on the rise.

Illustration: Profile shot of user with headphones

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“… they allow people with vision issues to access information, make choices and conduct their lives, education and business needs in a barrier-free manner.”

Screen magnification users rely on features and adjustments in their chosen products in order to complete tasks like finding and consuming information, conducting business, viewing videos and presentations, participating in educational opportunities, and more. Screen magnification software allows the user to increase and decrease the magnification of text and images to varying degrees. With some magnification software allowing the user to increase magnification on the screen in increments from 1x magnification all the way up to 36x magnification. Many screen magnification software programs also have features that allow users to adjust for other components affected by low vision.  

Common screen magnification features

In addition to the common magnification adjustments, here are some other features that are common with screen magnification software that allow users to adjust based on their specific needs.

  • Mouse pointer: It is common to provide ways to mark the mouse pointer location, such as with large crosshairs or a surrounding circle as well as the pointer’s size, and color.
  • Typing cursor: The typing cursor can be very difficult to find, so a feature to mark the typing “I beam” with adjustable size and color marks helps to provide ease in location and contrast.
  • Adjustable indicators: Adjustable indication for focus of on-screen objects, like a frame around active controls, or areas of content that may be read by a computer’s speech synthesizer. This helps with orientation, especially when a combination of screen magnification and screen reader software are being used. 
  • Brightness and contrast: Some users need the ability to control brightness and contrast. For example, viewing black text on white, and then being able to switch to yellow on black can be helpful. This is especially helpful as eyes become fatigued toward the later part of the work day.
  • Flexible use: Some users will magnify, explore, and use the full screen of content.  Some will opt for a magnified bar that extends the full width of the window and only magnifies a certain portion of the screen, others may opt for a square magnified rectangle that moves with the mouse pointer (kind of like a magnifying glass on-screen).
  • Speech synthesis: Some magnification products also provide speech synthesis to allow the user to “read” portions of text.  However, keep in mind that “pictures” of text are pictures, and not actually text.
  • Hot keys: Most screen magnification software packages have a series of hot keys that allow the user to make adjustments and navigate the screen quickly and easily.

Web accessibility considerations for screen magnification users

  • Descriptive text: Pictures typically do not magnify well with higher magnification, and so descriptive text should be provided.  But in addition, a good magnification software will recognize images as different from text, and treat them differently for people using high-contrast and reverse video features so that a screen magnification user can see them on screen. 
  • Font Clarity: Font clarity is critical.  Some fonts, when magnified are pixelated and become impossible to read.  Using a good font to begin with is crucial of course, but the magnification software will need to smooth and bold the font on the fly as the user adjusts magnification. 
  • Content layout: In a magnified view, not all of the content will fit on the screen at one time, so the user must pan smoothly.  For example, on a web page using 4x magnification, one sees only one fourth of the screen view and so will need to slide the mouse up, down, and sideways to explore the content and to find and use all the off-screen content, use drop boxes, edit fields, checkboxes,  “OK”, “Next”, “Checkout”, etc. buttons. Screen magnifier software will redraw so that panning around the screen provides smooth text. 

Things screen magnification software have in common

There are many forms of “low vision” and today, there are a variety of magnification products available with various features. What they all have in common is that, most importantly, they allow people with vision issues to access information, make choices and conduct their lives, education and business needs in a barrier-free manner. 

Websites, web pages, documents, and presentations should be constructed and maintained in ways that make sense structurally as well as functionally. For example, mouse-over fly-out menus and pop-ups can seriously interfere with a magnifier user’s experience.  

Several of the greatest difficulties in relying on magnification software are related to: finding information, links, buttons, etc.; gathering clear information without having to traverse large non-content areas, and navigating through a lot of advertisements and clutter. Listing items by left justifying them is very helpful for the screen magnification user as it cuts down on the need for panning around the screen and hunting for the next item. 

Popular screen magnification software

  • ZoomText: This is a popular screen magnification software program for the PC that combines several alternative features for easier viewing of the screen with low vision, along with a wide range of screen magnification, from 1x through 36x magnification, adjustable in increments.  
  • ZoomText Fusion: This is a newer screen magnification software program for the PC that combines ZoomText with a popular screen reader software called JAWS. The two software programs work in tandem with a series of key commands to control its features. 
  • MAGic: This stands for magnification-in colour. This has similar functions as ZoomText. It is available for PC users. 
  • Magnifier: Microsoft screen magnifier that is built into Windows 10, available through its accessibility features on a PC. This screen magnifier is not as robust, or as well organized as the  products mentioned above, but it comes free with Windows 10, where the other screen magnification programs need to be purchased separately.  
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