标签: lenses

As we get older we make an increasing number of accommodations to a changing reality. For example, my 84 year old father recently – finally! – gave up driving at night, a truly astonishing development considering his fierce independence. Surely one of the more common maladies is myopia, whose curse extends far into antiquity. Glasses were invented in the thirteenth century and have helped probably billions of people. A number of friends have gotten laser eye surgery to eliminate their need for eyeglasses. Many, though, find they still need reading glasses, and some now have found their eyes continue to deteriorate, so are faced with a need to repeat the procedure or go back to being four-eyed. Then there's the far-sightedness that commonly sets in during middle age. Those of us who have been merely myopic find we need different corrections for various distances, so wear bifocals or progressive lenses. The latter take some adaptation till one learns to follow the "point your nose where you want to see" dictum. It's a royal pain in the you know what. But, I'm thankful that the technology does allow us to see reasonably well. Office workers, though, are constantly changing their focal distance. Glance down at the desk. Then up at the monitor. Back down to the desk, over to the phone, punch some numbers into the calculator. Engineers then squint at the SOT-23 devices on a PCB (I keep a binocular microscope handy ). The oscilloscope or logic analyser is always at a very different distance than the computer screen, and the writing on it tends to be small and very hard to see. One friend cut a big hole at the back of his desk and built a low shelf. The monitor sits on the shelf, and fully half of that display is below desk level. He finds it much easier to focus this way. A couple of months ago my wife had cataract surgery in one eye. It was a really weird experience; the ophthalmologist asked what kind of lens she'd like. He recommended a little nearsightedness to help with her crafting. We live in an era of amazing technology. So now her eyes have wildly different lenses. The first set of glasses simply corrected for the two, but after a month of blinding headaches they made a new pair by, as they put it, "slabbing off" half of the lens of the unfixed eye. The result is a prismatic effect that supposedly alleviates the literal headaches of the mismatch. A week into the new lenses and things are still not good, so I made a new monitor stand that puts the thing much lower, right at desk level. The idea is to reduce the constant refocusing needed. We'll see how that plays out. But the experience left me once again thinking that we need a new tech for glasses, an embedded version of the age-old glass lens. For years I've dreamed of a tiny projector that could send images focused at infinity onto my glasses. Maybe using a tiny picoprojector, barely big enough to see and attached to the frames. Or the lenses themselves could modulate light to make images appear. One could have access to the world's knowledge without referring to a computer ( or, today, a tablet ). When someone you vaguely know walks up the system could project the person's name and other pertinent data on-lens. Nowadays they call this augmented reality, but most of those efforts are directed at augmenting on a cell phone screen. Going further, one wonders if it would be possible to project a corrective image on a lens, to resolve the near- and far-sightedness, the astigmatism and perhaps even cataract cloudiness. Think the Hubble repair in miniature. Glasses are an opportunity, a display device one already lugs around, and one that is mostly unobtrusive. The right technology will, probably in the near future, radically reinvent the way we correct our vision and even gain access to information. I can't wait.