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Ask Slashdot: How to Exploit Post-Cataract Ultraviolet Vision?

xmas2003 writes "I recently had cataract surgery with a Crystalens implant. With my cloudy yellowing (UV-filtering) natural lens removed, I see the world in a new light (more on that in a moment) as everything is brighter and colors are more vivid ... plus in focus. As a typical Slashdot reader, I've been myopic since childhood, so it's wonderful not to have to wear glasses/contacts for distance. One interesting oddity is that I can now see ultraviolet light — it seems that there are a few people who have photoreceptors sensitive below 400nm into the UV spectrum. I've done some testing with a Black Light and UV filter to confirm this but would love to do more conclusive testing such as using a Monochromator — anyone in the Boulder, Colorado area have access to one? And any suggestions from Slashdot readers on how I can further explore this phenomenon? While I can't see dead people, I guess I have a 'superpower' ... although I'm not sure a middle-aged suburbanite dad should don purple tights and cape to become a crime-fighter!"

6 of 350 comments (clear)

  1. Re:Is there anything.. by nickersonm · · Score: 5, Informative

    Flowers are often more varied in the UV than in the standard visible light range.

  2. Re:First step (or post) by Manos_Of_Fate · · Score: 5, Informative

    Ultragirl. I didn't even click the links yet, because I already know that only females are gifted with vision in or near the ultraviolet part of the spectrum.

    although I'm not sure a middle-aged suburbanite dad should don purple tights and cape to become a crime-fighter!"

    You need to take some remedial biology lessons, I think.

    --
    Isn't enough that I ruined a pony, making a gift for you?
  3. Re:Dangerous by subreality · · Score: 5, Informative

    UV is a very wide spectrum. Near-UV isn't too scary.

    UV-A (400-315 nm) is OK for short-term exposure. Your pupils won't constrict like they do for visible light, so keep the intensity low. Plain old blacklights are 350-400nm with the peak at 365nm, plus a small peak in the very bottom of the visible spectrum (which is the purple glow).

    UV-B (315-280 nm) will probably be invisible, and it will do bad things to your eyes, so please stick to very low intensities if you want to fool with this. Read up on the risks first.

    UV-C (280-100 nm) is utterly hostile to biology - the upper atmosphere filters this range out so life never evolved mechanisms to deal with it. Actually, UV-C is hostile to damn near everything: just from my own experience, it bleaches everything, and most plastics will degrade and become brittle with mere hours of exposure. I've test-fired a 185nm lamp in the open for a few seconds (wearing goggles!) and even across the room you can instantly smell ozone forming as it starts ripping oxygen apart. Stay away!

  4. Re:First step (or post) by JWSmythe · · Score: 4, Informative

    Before you go off calling someone a liar, maybe you should check up on it first. Google "see ultravilot". I just replied to another of your messages. I have a replacement lens in one eye, so I see both ways (normal and altered vision).

    The following are quotes from http://www.guardian.co.uk/science/2002/may/30/medicalscience.research

    These harmful effects are reduced by the lens, which absorbs UV and prevents it entering the eye. When the lens becomes opaque due to cataracts, it may be surgically removed, and can be replaced with an artificial lens. Even with the lens removed (a condition known as aphakia) the patient can still see, as the lens is only responsible for about 30% of the eyes' focusing power.

    However, aphakic patients report that the process has an unusual side effect: they can see ultraviolet light. It is not normally visible because the lens blocks it. Some artificial lenses are also transparent to UV with the same effect. The receptors in the eye for blue light can actually see ultraviolet better than blue. Military intelligence is said to have used this talent in the second world war, recruiting aphakic observers to watch the coastline for German U-boats signalling to agents on the shore with UV lamps. ...

    An illustration of how ultraviolet appears is provided by the Impressionist painter Claude Monet. Following cataract surgery in 1923, his colour palette changed significantly; after the operation he painted water lilies with more blue than before. This may be because after lens removal he could see ultraviolet light, which would have given a blue cast to the world.

    --
    Serious? Seriousness is well above my pay grade.
  5. Re:First step (or post) by RobbieThe1st · · Score: 4, Informative

    Not really; The paints are made from different materials which may or may not do the same thing in the ultraviolet range as the real objects he was painting.

  6. Re:Dangerous by subreality · · Score: 4, Informative

    Fortunately we were all living underwater back then. Before the Oxygen Catastrophe we were really damn deep where there's no light at any wavelength. Even the green things stayed well under the surface until the ozone layer was established.

    Nothing has ever lived in the presence of UVC. There are few absolutes in biology, and I certainly want my readers to consider the implications of that before they go experimenting with short wavelengths: life evolves to fill any niche it can, but it has never gone there, and neither should you.