It seems to me that the given explanation ("patterns of both constructive and destructive interference") would depend strongly on the exact frequency of the light. So maybe it is not correctly stated.
However, the basic claim seems accurate. Here is Zalevsky's paper:
You have to pay to get the full text, but the abstract says:
> This technology is capable of simultaneously correcting all refractive errors, such as myopia, hyperopia, presbyopia, regular/irregular astigmatism, as well as their combinations.
My goodness.
Curiously, the abstract suggests that this idea is "designed to employ neural adaptation processes". It also says that the effect "is achieved by exploiting the capacity of the visual system for adaptation to contrast".
Agreed, I can't figure out how this can work for all wavelengths. But, then, I can't figure out how it would work at all, so what do I know? Perhaps this calls for a trip to the MIT library.
One wonders if too much reliance on "adaptations of the visual system" is going to cause problems. For example, will you wind up training your brain in such a fashion that you'll need several hours or days of retraining to see with your glasses off? Visual processing is famously plastic, but one wonders what the timescale of the plasticity is.
Right now, you can get opaque black plastic glasses with an array of pinholes. These work to correct a variety of focusing problems, since pinhole cameras have an infinite depth of field. The drawback is that pinholes let in very little light, so although the image is in focus, it is very dim. And, of course, the image between the pinholes is not as good as it is near the pinholes.
I don't have access to the full text article so I can't say for certain but the article makes it sound like the effect is accomplished in a fashion similar to phase contrast microscopy.
The basic concept of phase contrast is that certain objects (notably, monolayers of biological specimens) don't greatly affect the amplitude of light passing through them. IOW, viewed under "normal" optics, they would appear transparent.
On the other hand it was noticed that these objects do cause the phase of light to shift as it passes through the specimens. The basic idea is that you create a system that has light passing through the specimen in two paths. The major light path is dimmed and accelerated by half a wavelength. This gives us a situation of theoretically perfect destructive interference at the point of observation. When the reference light waves pass through a phase object, it changes the phase of the light and introduces perturbances to the completely destructive interference which results in an observable image of the specimen.
The reason these glasses remind me of phase contrast is the concentric circles milled to specific depths and widths (which is one of two important pieces of a phase contrast microscope, the objective). Also, the article describes the effects based in terms of phase:
The rings shift the phase of the light waves passing
through the lens, leading to patterns of both
constructive and destructive interference. Using a
computer model to calculate how changes in the diameter
and position of the rings alter the pattern, Zalevsky
came up with a design that creates a channel of
constructive interference perpendicular to the lens
through each of the 25 structures. Within these
channels, light from both near and distant objects is
in perfect focus.
I never took the optics courses in school so I'm not able to connect how the phase properties are leveraged for focus. The only thing that comes to mind is that they're using phase differences to selectively destruct out of focus rays and reinforcing in focus rays (hand wavy factor: 8.6 of 10).
Elementary yet interesting. I just "constructed" a pinhole by curling my index finger in my thumb, and could read letters on this page. At the same range without wearing contacts or glasses, I am unable to separate words. Only lines of text.
I use glasses in the evening and contacts in the morning, so the dimming could perhaps be beneficial for circadian rhythms if I need to use a computer, although I recognize that probably has more to do with the spectrum of light than the intensity.
Extraordinary claims require extraordinary evidence though, so to be perfectly honest, I'd like to see a good number of people wearing these new lenses before concluding that they are as amazing as they are being presented as being.
It seems to me that the given explanation ("patterns of both constructive and destructive interference") would depend strongly on the exact frequency of the light. So maybe it is not correctly stated.
However, the basic claim seems accurate. Here is Zalevsky's paper:
http://www.opticsinfobase.org/abstract.cfm?URI=ol-35-18-3066
You have to pay to get the full text, but the abstract says:
> This technology is capable of simultaneously correcting all refractive errors, such as myopia, hyperopia, presbyopia, regular/irregular astigmatism, as well as their combinations.
My goodness.
Curiously, the abstract suggests that this idea is "designed to employ neural adaptation processes". It also says that the effect "is achieved by exploiting the capacity of the visual system for adaptation to contrast".
Wow.