Functional Eye Test Issues
Most eye tests are done with a chart on the far wall. However, some people have difficulty with convergence of their eyes on close objects. You can test for this by getting the learner to read a series of random number sequences in descending font size, starting at around 40pt font.
What to do if small font is harder
If they struggle as the font size gets smaller, down to about 15pt or below, then it is likely that reading will be difficult.
We recommend the following eye-tracking exercises completed at high frequency over 10 days.
What to do if white background font is harder
If they struggle more when the numbers are on a white background, then they may have some visual stress (also known as Irlen Syndrome or contrast sensitivity). This can cause visual distortions of text, like shimmering, movement or wavy letters.
If this is the case, then using a tinted overlay will make a night-and-day difference to their reading.