Pixels don't have contrast or well-defined edges. Vision RX20 Review They are bright at the center and diminish in intensity toward their edges, which makes it very difficult for the eyes to maintain focus and remain fixed onto these images. Printed materials are typically dense black characters with well-defined edges against a white background and our eyes can easily maintain focus on these.
Our eyes tend to stay open for long periods of time when focusing on a computer monitor, they can dry out quickly, causing damage. Our eyes also strain to regain focus. This continuous flexing of the eyes' focusing muscles creates fatigue and the burning, tired-eyes feeling that is so common after spending time in front of the computer. We tend to blink less often than normal while viewing a computer monitor or concentrating on near objects. Staring and decreased frequency of blinking can cause the eyes to dry out leading to redness, burning sensation, soreness, stinging, itchiness, and dryness. Focusing the eyes on a computer monitor for uninterrupted periods of time causes CVS (Computer Vision Syndrome).
CVS refers to the visual problems experienced by computer use. CVS encompasses different symptoms, and treatments. In addition to the eye problems mentioned earlier there are also vision problems including blurred vision (both near and far), difficulty changing focus, double vision, glare, flickering sensations, and temporary changes in color perception. And there is general discomfort including headaches, neck tension or pain, shoulder tension or pain, back pain, excessive fatigue, irritability, and drowsiness.
https://letsfireurbossnow.com/vision-rx20-review/