Engineers produce a fisheye lens that’s completely flat
news.mit.edu
news.mit.edu
https://www.merriam-webster.com/dictionary/laser
>> "2 : something resembling a laser beam in accuracy, speed, or intensity "
I gave up on fighting "CPU means the entire computer" a long time ago.
"Many people" have taken first year physics, or at least read a wikipedia article, and understand that the defining feature of a laser is its coherence.
But, sure. It's 2020. We live in a post-factual society, words have no meaning and it's impossible to know anything. Why resist?
the new fisheye lens consists of a single flat, millimeter-thin piece of glass covered on one side with tiny structures that precisely scatter incoming light to produce panoramic images
Except I don't think it is. It's probably more like a diffraction grating or a hologram. You can actually make a flat lens by creating a hologram of a real lens and it will be flat.
What are the downsides?
(In particular, wave theory is not needed to predict the behavior of classical lenses.)
This is slightly unclear. I meant more specifically:
[...] which has small structures that change the phase of the light, which, in turn, causes it to constructively or destructively interfere [...]
But i will read the paper later.
Also in the video you can see spatial ringing, which is highly indicative of coherent light (single wavelength, like in a laser.)
This is still a cool discovery and could definitely have a lot of important applications, but it's important to clarify what this is, and what it isn't.
> 3D artistic illustration of the wide-field-of-view metalens capturing a 180° panorama of MIT’s Killian Court and producing a high-resolution monochromatic flat image.
My guess is that it is only good for monochromatic light.
Does anyone know how much of a limitation that'd be in practice though? CCDs are monochromatic too, which we deal with using either Bayer filters (usually RGGB IIRC) or (in fancier high end stuff) a splitter prism leading to 3 separate CCDs. Modern computational photography is also increasingly able to do sensor fusion, even between different cameras. I can see how making use of this would still be an extra challenge in a small form factor, because normally the split/filter happens after the lens which simplifies things a lot. Having to do 3x multisensor fusion with meta material fisheye only definitely would be more effort and bulkier. Seems like it might still be pretty useful though depending on final cost? Otherwise maybe it'll end up niche, but it's really cool research anyway.
Just too much stuff missing from the article to actually judge for technical merit.
And plus making one for visible light is likely the main challenge as micro machining precision optics is not subject to moore’s law type scaling. Though I wouldn’t put it past Apple to sink billions into it if it helps making camera modules a few mm thinner.
Isn't a typical consumer fish eye lens for an iPhone a couple of cm in depth? Sounds like we're talking a more than a few mm here
If it works for visible light too, Apple seems like a ripe buyer. Supports a thin enclosure and an obvious camera upgrade thus a win for them.
Will be interesting if it's a gross exaggeration.
Click bait. Not "completely flat" at all.
> the new fisheye lens consists of a single flat, millimeter-thin piece of glass covered on one side with tiny structures that precisely scatter incoming light to produce panoramic images.
With a thinness of a millimeter, I'd say that's flat. The "tiny structures" are in the form of a film, which further qualifies as flat.
> Their new metalens is a single transparent piece made from calcium fluoride with a thin film of lead telluride deposited on one side. The team then used lithographic techniques to carve a pattern of optical structures into the film.
> Each structure, or “meta-atom,” as the team refers to them, is shaped into one of several nanoscale geometries, such as a rectangular or a bone-shaped configuration, that refracts light in a specific way.
The 3µm-wide structures in TFA deviate <1µm from the surface, so it's even flatter than glass, and your objection sounds rather petty.