Monday, November 14, 2011

Lasers can make brown eyes blue--but should they?

Gail Overton
Senior Editor
Laser Focus World

The daily news posting at entitled "Laser turns brown eyes blue" generated much discussion on LinkedIn. The comments weren't centered around how 'cool' or 'neat' the concept was, but instead focused on the technology details and the philosophical aspects of the procedure. After all, the LinkedIn audience to whom we share our Laser Focus World postings is not your average non-technical crowd; these are photonics industry professionals who are clearly concerned about how something works and what impact it has on society as a whole.

Turning brown eyes to blue may seem magical to a non-laser audience, but it is merely an extension of laser aesthetics--a topic profiled in our Photonics Applied feature series for November called "Looking good with lasers." Laser hair removal works on the principle of targeting melanin in the hair shaft and through laser heat, destroying the melanin and the hair follicle. Laser aesthetics also includes wrinkle removal, liposuction, and tattoo and lesion removal--different wavelengths of light attack different colored pigments in the tattoo or lesion, and it really works!

But even though lasers can turn brown eyes blue by targeting melanin, should they? One LinkedIn respondent said that they wished scientific research could be channeled into curing unsolved medical problems that we suffer rather than in trying to alter one's appearance for cosmetic reasons. I wholeheartedly agree; however, my sentiments will not change the fact that as long as people have "disposable incomes", money will be spent on luxuries. I was amazed to learn while researching the laser aesthetics article that teeth whitening is a $5.5 billion dollar global market, while the entire laser market is around $7 billion. Maybe we're all in the wrong business!

Still other LinkedIn comments focused on the technology. "Mankind has always sought to change his/her appearance--hair color, skin, and eyes," said Gennady Medvedkin. "Tomorrow we may witness artificial eyes made from silicon."

Medvedkin says that image sensors are really artificial eyes with great spatial resolution and color-sensing capabilities that can even exceed the capabilities of human vision. Thin silicon plates the size of the pupil could be implanted within the human body, completely replacing the eye, and recent computer algorithms allow extensions of the dynamic range in sensors up to 140 dB that are comparable to the human eye. Medvedkin says that the eye must adapt to very low light intensities for minutes and sometimes hours, whereas CMOS image sensors operate in the millisecond to second time range at low voltage with great success.

Personally, I'll keep my green eyes green and will be glad when this story fades from my memory; I'm getting tired of humming the "Don't it make my brown eyes blue" song from Crystal Gayle!

No comments:

Post a Comment