Simply using a larger monitor won't help you see the information on the screen any better. However, if you need to magnify that information significantly, you'll reduce the amount of visible information on the screen; in that case, having a larger monitor can be a good alternative. Keep in mind that large monitors are usually expensive, very heavy to carry, and use up a great deal of space on a desk or tabletop.
Having a 20" monitor or larger will definitely affect the overall look and size of the material on the page you are viewing. For some people this may be enough. However, people with a severe vision loss will most likely change the font size of printed material to enhance reading comfort, or use a software program which magnifies the printed material comparable to that of an electronic video magnifier (or closed circuit television "CCTV") which can magnify print up to 70 times.
Here is an illustration of normal size font displayed on your computer:
And here is how a screen magnification software program may render the computer screen with enlarged font:
If a larger monitor and the use of a software enlargement (screen magnification) program are not working for you, you might want to consider using a screen reader software program that has speech output.
Before making this investment, we suggest you try some of the easy-to-implement strategies discussed on our site [1] and/or the magnification software programs listed below.
Visit a computer store and try different size monitors and see for yourself whether size makes a difference for you. Remember, everyone's vision is different and what works for one person may not be the solution for another.
Links:
[1] http://www.visionaware.org/accessibility_help