This man went in to have his vision restored, and instead became slightly superhuman.
Alek Komar, a former Air Force officer and engineer who says his "eyes have always been a bit of a problem," spent much of his life wearing glasses and contact lenses to battle nearsightedness. By 2010, at age 46, he noticed that his right eye in particular was becoming a problem, and was diagnosed with a cataract. In 2011, Komar elected to have Crystalens implants surgically placed in his eyes to both deal with the cataracts and eliminate the need for glasses. When the surgery he was over, he found that he wasn't just seeing better. He was seeing more.
Komar can now see parts of the light spectrum lower than what humans are supposed to be able to detect (as explained by his example photo above). He can see ultraviolet light.
"I've done various 'tests' of my UV vision," Komar wrote on a webpage he's used to document his experiences. "It's a little harder now that both eyes have been done (which I'm very thankful for from a visual acuity perspective), since I can not compare/test myself with and without natural lens. I can see much better than others in a dark room lit only with a 'black light' ... although ironically, other people can see fluorescence (stuff that glows in the dark) better than me because it stands out more - i.e. the rest of the room is dark for them!"
At first Komar's friends and family thought he might have just been imaginging this new abilities, but then an engineer at Hewlett-Packard offered to test his vision using a Monochromator, which is capable of displaying various wavelengths of light in very small increments. It was confirmed that Komar does indeed see farther down the spectrum of light than most humans, and he may not be the only one. According to Komar, he's been contacted by others who've received the same implants and experienced similar effects.
Komar's story is fascinating or many reasons. It's an example of the limitations of our own eyes and ways we can unlock new potential for them, as well as an example of the adaptability of our brains. It's also a possible glimpse into future eye surgery technology. Who knows? One day we might be able to give someone the ability to see perfectly in the dark.
If you're interested in a more detailed account of Komar's journey (along with numerous amusing visual examples of how he sees the world), you can head over to his site.