Around age 40, the lens becomes thicker and flatter and the pupil becomes less able to change diameter, reducing the amount of light that reaches the retina. Sensitivity to glare appears to increase with age. Individuals may be less able to discriminate between certain colors, and sensitivity to contrast may be reduced. There is generally reduction in the size of the visual field. A reduction in eye lubrication is also associated with age, particularly for menopausal and post-menopausal women.
Age also appears to play a role, with reported problems increasing among older individuals.
These movements stress the visual system, particularly the musculature. Computer Design Considerations Facilitate adjustability of monitors . An adjustability range between 5 degrees towards the user and 20 degrees away from the user may be necessary to avoid glare. Monitors that could easily be adjusted with, for example, the push of a button could accommodate manual disabilities and increase the likelihood that users would adjust their monitors properly. Maximize the ability to adjust luminance .