now, here's the rig I'd love to see with this: take a hundred of them and position them like a bug's eye to see what could be done with that. there'd be so much overlapping coverage that 3D would be possible, yet the parallax would be so small that makes me wonder how much depth would be discernible
> After fabrication of the meta-optic, we account for fabrication error by performing a PSF calibration step. This is accomplished by using an optical relay system to image a pinhole illuminated by fiber-coupled LEDs. We then conduct imaging experiments by replacing the pinhole with an OLED monitor. The OLED monitor is used to display images that will be captured by our nano-optic imager.
But shooting a real chameleon is irrelevant to what they're trying to demonstrate here.
At the scales they're working at here ("nano-optics"), there's no travel distance for chromatic distortion to take place within the lens. Therefore, whether they're shooting a 3D scene (a chameleon) or a 2D scene (an OLED monitor showing a picture of a chameleon), the light that makes it through their tiny lens to hit the sensor is going to be the same.
(That's the intuitive explanation, at least; the technical explanation is a bit stranger, as the lens is sub-wavelength – and shaped into structures that act as antennae for specific light frequencies. You might say that all the lens is doing is chromatic distortion — but in a very controlled manner, "funnelling" each frequency of inbound light to a specific part of the sensor, somewhat like a MIMO antenna "funnels" each frequency-band of signal to a specific ADC+DSP. Which amounts to the same thing: this lens doesn't "see" any difference between 3D scenes and 2D images of those scenes.)
Is this basically a visible-wavelength beamsteering phased array?
It's a good read; I don't think the extrapolation of one technical advance has ever been done better.
> Then, a physics-based neural network was used to process the images captured by the meta-optics camera. Because the neural network was trained on metasurface physics, it can remove aberrations produced by the camera.
Generally it's probably wise to be skeptical of anything that appears to get around the diffraction limit.
You’re right that it might fail on noise with resolution fine enough to break assumptions from the NN training set. But that’s not a super common application for cameras, and traditional cameras have their own limitations.
Not saying we shouldn’t be skeptical, just that there is a plausible mechanism here.
Multilevel fractal noise specifically would give an indication of how fine you can go.
I agree that measuring against such a test would be interesting, but I'm not sure it's possible or desirable for any camera tech to produce an objectively "true" pixel by pixel value. This new approach may fail/cheat in different ways, which is interesting but not disqualifying to me.
I was really skeptical of this since the article conveniently doesn't include any photos taken by the nano-camera, but there are examples [1] in the original paper that are pretty impressive.
[1] https://www.nature.com/articles/s41467-021-26443-0/figures/2