temporary damage to the surface of the cornea can cause eyes to water and feel like you’ve got sand or grit in them so you tend to blink a lot more. you may have a bit of a headache as well.
how does the sun damage our eyes?
with long exposure to excessive amounts of sun, particularly in a dry climate, the cornea, which is the transparent tissue that protects the iris and pupil, can actually start to scar. the lens absorbs most of the ultraviolet rays that enter the eye and, over time, repeated exposure to those rays can accelerate the development of cataracts.
most of the damaging rays, though, are removed by the time the light gets to the lens and passes down to the retinas, so there isn’t as big an issue in terms of damage to the retina with sun exposure. [research hasn’t] really been able to correlate an increased risk of conditions like macular degeneration with sun exposure over the years, but there is a clear association with the development of cataracts.
how do our eyes adjust going from bright to dim light?
the chief mechanism we have to regulate the amount of light going in the eye is the iris, which gets bigger and smaller depending on the amount of light that we’re exposed to. [we have an] aversion reflex, in that it’s just uncomfortable enough to look into bright light that we look away or close our eyes to protect them.
why do we see spots in our eyes after looking at a bright light?
when we look into a bright light, [the eye’s] pigments are bleached and you can no longer react to light or realize light is there until they’re regenerated. if it’s a short exposure, like a flash bulb going off, it takes a matter of a few seconds. but with longer periods of exposure to brighter light, that whole process takes much longer.
how extra careful should you be after cataract or laser surgery?
in terms of light exposure, not so much. cataract develops very slowly; it actually lets less and less light through the lens of the eye. so when the lens is removed and an artificial lens is placed in cataract surgery, the vision is much brighter, the colour perception changes immediately. so from a light point of view, there really isn’t a particular concern.